Commit Graph

2864 Commits

Author SHA1 Message Date
Vasily Gorbik 95e61b1b5d s390/setup: init jump labels before command line parsing
Command line parameters might set static keys. This is true for s390 at
least since commit 6471384af2 ("mm: security: introduce init_on_alloc=1
and init_on_free=1 boot options"). To avoid the following WARN:

static_key_enable_cpuslocked(): static key 'init_on_alloc+0x0/0x40' used
before call to jump_label_init()

call jump_label_init() just before parse_early_param().
jump_label_init() is safe to call multiple times (x86 does that), doesn't
do any memory allocations and hence should be safe to call that early.

Fixes: 6471384af2 ("mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options")
Cc: <stable@vger.kernel.org> # 5.3: d6df52e9996d: s390/maccess: add no DAT mode to kernel_write
Cc: <stable@vger.kernel.org> # 5.3
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2020-06-29 16:28:39 +02:00
Christian Borntraeger 827c491392 s390/debug: avoid kernel warning on too large number of pages
When specifying insanely large debug buffers a kernel warning is
printed. The debug code does handle the error gracefully, though.
Instead of duplicating the check let us silence the warning to
avoid crashes when panic_on_warn is used.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2020-06-23 14:05:55 +02:00
Vasily Gorbik 998f5bbe3d s390/kasan: fix early pgm check handler execution
Currently if early_pgm_check_handler is called it ends up in pgm check
loop. The problem is that early_pgm_check_handler is instrumented by
KASAN but executed without DAT flag enabled which leads to addressing
exception when KASAN checks try to access shadow memory.

Fix that by executing early handlers with DAT flag on under KASAN as
expected.

Reported-and-tested-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2020-06-23 14:05:50 +02:00
Sven Schnelle e64a1618af s390: fix system call single stepping
When single stepping an svc instruction on s390, the kernel is entered
with a PER program check interruption. The program check handler than
jumps to the system call handler by reloading the PSW. The code didn't
set GPR13 to the thread pointer in struct task_struct. This made the
kernel access invalid memory while trying to fetch the syscall function
address. Fix this by always assigned GPR13 after .Lsysc_per.

Fixes: 0b0ed657fe ("s390: remove critical section cleanup from entry.S")
Reported-and-tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2020-06-23 14:05:45 +02:00
Collin Walling a23816f3cd s390/setup: diag 318: refactor struct
The diag 318 struct introduced in include/asm/diag.h can be
reused in KVM, so let's condense the version code fields in the
diag318_info struct for easier usage and simplify it until we
can determine how the data should be formatted.

Signed-off-by: Collin Walling <walling@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20200622154636.5499-2-walling@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-06-23 09:16:48 +02:00
Linus Torvalds 1566feea45 s390 fixes for 5.8-rc2
- Few ptrace fixes mostly for strace and seccomp_bpf kernel tests
   findings.
 
 - Cleanup unused pm callbacks in virtio ccw.
 
 - Replace kmalloc + memset with kzalloc in crypto.
 
 - Use $(LD) for vDSO linkage to make clang happy.
 
 - Fix vDSO clock_getres() to preserve the same behaviour as
   posix_get_hrtimer_res().
 
 - Fix workqueue cpumask warning when NUMA=n and nr_node_ids=2.
 
 - Reduce SLSB writes during input processing, improve warnings and
   cleanup qdio_data usage in qdio.
 
 - Few fixes to use scnprintf() instead of snprintf().
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Merge tag 's390-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Vasily Gorbik:

 - a few ptrace fixes mostly for strace and seccomp_bpf kernel tests
   findings

 - cleanup unused pm callbacks in virtio ccw

 - replace kmalloc + memset with kzalloc in crypto

 - use $(LD) for vDSO linkage to make clang happy

 - fix vDSO clock_getres() to preserve the same behaviour as
   posix_get_hrtimer_res()

 - fix workqueue cpumask warning when NUMA=n and nr_node_ids=2

 - reduce SLSB writes during input processing, improve warnings and
   cleanup qdio_data usage in qdio

 - a few fixes to use scnprintf() instead of snprintf()

* tag 's390-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: fix syscall_get_error for compat processes
  s390/qdio: warn about unexpected SLSB states
  s390/qdio: clean up usage of qdio_data
  s390/numa: let NODES_SHIFT depend on NEED_MULTIPLE_NODES
  s390/vdso: fix vDSO clock_getres()
  s390/vdso: Use $(LD) instead of $(CC) to link vDSO
  s390/protvirt: use scnprintf() instead of snprintf()
  s390: use scnprintf() in sys_##_prefix##_##_name##_show
  s390/crypto: use scnprintf() instead of snprintf()
  s390/zcrypt: use kzalloc
  s390/virtio: remove unused pm callbacks
  s390/qdio: reduce SLSB writes during Input Queue processing
  selftests/seccomp: s390 shares the syscall and return value register
  s390/ptrace: fix setting syscall number
  s390/ptrace: pass invalid syscall numbers to tracing
  s390/ptrace: return -ENOSYS when invalid syscall is supplied
  s390/seccomp: pass syscall arguments via seccomp_data
  s390/qdio: fine-tune SLSB update
2020-06-20 12:31:08 -07:00
Christoph Hellwig fe557319aa maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
Better describe what these functions do.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-17 10:57:41 -07:00
Christian Brauner 9b4feb630e
arch: wire-up close_range()
This wires up the close_range() syscall into all arches at once.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Jann Horn <jannh@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: linux-api@vger.kernel.org
Cc: linux-alpha@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: linux-arch@vger.kernel.org
Cc: x86@kernel.org
2020-06-17 00:07:38 +02:00
Vincenzo Frascino 478237a595 s390/vdso: fix vDSO clock_getres()
clock_getres in the vDSO library has to preserve the same behaviour
of posix_get_hrtimer_res().

In particular, posix_get_hrtimer_res() does:
    sec = 0;
    ns = hrtimer_resolution;
and hrtimer_resolution depends on the enablement of the high
resolution timers that can happen either at compile or at run time.

Fix the s390 vdso implementation of clock_getres keeping a copy of
hrtimer_resolution in vdso data and using that directly.

Link: https://lkml.kernel.org/r/20200324121027.21665-1-vincenzo.frascino@arm.com
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[heiko.carstens@de.ibm.com: use llgf for proper zero extension]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-06-16 13:44:05 +02:00
Nathan Chancellor 2b2a25845d s390/vdso: Use $(LD) instead of $(CC) to link vDSO
Currently, the VDSO is being linked through $(CC). This does not match
how the rest of the kernel links objects, which is through the $(LD)
variable.

When clang is built in a default configuration, it first attempts to use
the target triple's default linker, which is just ld. However, the user
can override this through the CLANG_DEFAULT_LINKER cmake define so that
clang uses another linker by default, such as LLVM's own linker, ld.lld.
This can be useful to get more optimized links across various different
projects.

However, this is problematic for the s390 vDSO because ld.lld does not
have any s390 emulatiom support:

https://github.com/llvm/llvm-project/blob/llvmorg-10.0.1-rc1/lld/ELF/Driver.cpp#L132-L150

Thus, if a user is using a toolchain with ld.lld as the default, they
will see an error, even if they have specified ld.bfd through the LD
make variable:

$ make -j"$(nproc)" -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- LLVM=1 \
                       LD=s390x-linux-gnu-ld \
                       defconfig arch/s390/kernel/vdso64/
ld.lld: error: unknown emulation: elf64_s390
clang-11: error: linker command failed with exit code 1 (use -v to see invocation)

Normally, '-fuse-ld=bfd' could be used to get around this; however, this
can be fragile, depending on paths and variable naming. The cleaner
solution for the kernel is to take advantage of the fact that $(LD) can
be invoked directly, which bypasses the heuristics of $(CC) and respects
the user's choice. Similar changes have been done for ARM, ARM64, and
MIPS.

Link: https://lkml.kernel.org/r/20200602192523.32758-1-natechancellor@gmail.com
Link: https://github.com/ClangBuiltLinux/linux/issues/1041
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
[heiko.carstens@de.ibm.com: add --build-id flag]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-06-16 13:44:05 +02:00
Chen Zhou 99448016ac s390/protvirt: use scnprintf() instead of snprintf()
snprintf() returns the number of bytes that would be written,
which may be greater than the the actual length to be written.

uv_query_facilities() should return the number of bytes printed
into the buffer. This is the return value of scnprintf().
The other functions are the same.

Link: https://lkml.kernel.org/r/20200509085608.41061-4-chenzhou10@huawei.com
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-06-16 13:44:05 +02:00
Chen Zhou 92fd356514 s390: use scnprintf() in sys_##_prefix##_##_name##_show
snprintf() returns the number of bytes that would be written,
which may be greater than the the actual length to be written.

show() methods should return the number of bytes printed into the
buffer. This is the return value of scnprintf().

Link: https://lkml.kernel.org/r/20200509085608.41061-3-chenzhou10@huawei.com
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-06-16 13:44:05 +02:00
Sven Schnelle 873e5a763d s390/ptrace: fix setting syscall number
When strace wants to update the syscall number, it sets GPR2
to the desired number and updates the GPR via PTRACE_SETREGSET.
It doesn't update regs->int_code which would cause the old syscall
executed on syscall restart. As we cannot change the ptrace ABI and
don't have a field for the interruption code, check whether the tracee
is in a syscall and the last instruction was svc. In that case assume
that the tracer wants to update the syscall number and copy the GPR2
value to regs->int_code.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-06-16 13:44:04 +02:00
Sven Schnelle 00332c16b1 s390/ptrace: pass invalid syscall numbers to tracing
tracing expects to see invalid syscalls, so pass it through.
The syscall path in entry.S checks the syscall number before
looking up the handler, so it is still safe.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-06-16 13:44:04 +02:00
Sven Schnelle cd29fa7980 s390/ptrace: return -ENOSYS when invalid syscall is supplied
The current code returns the syscall number which an invalid
syscall number is supplied and tracing is enabled. This makes
the strace testsuite fail.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-06-16 13:44:04 +02:00
Sven Schnelle 664f5f8de8 s390/seccomp: pass syscall arguments via seccomp_data
Use __secure_computing() and pass the register data via
seccomp_data so secure computing doesn't have to fetch it
again.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-06-16 13:44:04 +02:00
Michel Lespinasse d8ed45c5dc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Mike Rapoport 65fddcfca8 mm: reorder includes after introduction of linux/pgtable.h
The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include
of the latter in the middle of asm includes.  Fix this up with the aid of
the below script and manual adjustments here and there.

	import sys
	import re

	if len(sys.argv) is not 3:
	    print "USAGE: %s <file> <header>" % (sys.argv[0])
	    sys.exit(1)

	hdr_to_move="#include <linux/%s>" % sys.argv[2]
	moved = False
	in_hdrs = False

	with open(sys.argv[1], "r") as f:
	    lines = f.readlines()
	    for _line in lines:
		line = _line.rstrip('
')
		if line == hdr_to_move:
		    continue
		if line.startswith("#include <linux/"):
		    in_hdrs = True
		elif not moved and in_hdrs:
		    moved = True
		    print hdr_to_move
		print line

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport ca5999fde0 mm: introduce include/linux/pgtable.h
The include/linux/pgtable.h is going to be the home of generic page table
manipulation functions.

Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and
make the latter include asm/pgtable.h.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport e31cf2f4ca mm: don't include asm/pgtable.h if linux/mm.h is already included
Patch series "mm: consolidate definitions of page table accessors", v2.

The low level page table accessors (pXY_index(), pXY_offset()) are
duplicated across all architectures and sometimes more than once.  For
instance, we have 31 definition of pgd_offset() for 25 supported
architectures.

Most of these definitions are actually identical and typically it boils
down to, e.g.

static inline unsigned long pmd_index(unsigned long address)
{
        return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}

static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
        return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}

These definitions can be shared among 90% of the arches provided
XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined.

For architectures that really need a custom version there is always
possibility to override the generic version with the usual ifdefs magic.

These patches introduce include/linux/pgtable.h that replaces
include/asm-generic/pgtable.h and add the definitions of the page table
accessors to the new header.

This patch (of 12):

The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the
functions involving page table manipulations, e.g.  pte_alloc() and
pmd_alloc().  So, there is no point to explicitly include <asm/pgtable.h>
in the files that include <linux/mm.h>.

The include statements in such cases are remove with a simple loop:

	for f in $(git grep -l "include <linux/mm.h>") ; do
		sed -i -e '/include <asm\/pgtable.h>/ d' $f
	done

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Dmitry Safonov 9cb8f069de kernel: rename show_stack_loglvl() => show_stack()
Now the last users of show_stack() got converted to use an explicit log
level, show_stack_loglvl() can drop it's redundant suffix and become once
again well known show_stack().

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Dmitry Safonov 8539c1288d s390: add show_stack_loglvl()
Currently, the log-level of show_stack() depends on a platform
realization.  It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).

Furthermore, it forces the logic decision from user to an architecture
side.  In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages.  And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.

Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers.  Also, it will consolidate
printings with headers.

Introduce show_stack_loglvl(), that eventually will substitute
show_stack().

[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lkml.kernel.org/r/20200418201944.482088-29-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:11 -07:00
Linus Torvalds 23fc02e36e s390 updates for the 5.8 merge window
- Add support for multi-function devices in pci code.
 
 - Enable PF-VF linking for architectures using the
   pdev->no_vf_scan flag (currently just s390).
 
 - Add reipl from NVMe support.
 
 - Get rid of critical section cleanup in entry.S.
 
 - Refactor PNSO CHSC (perform network subchannel operation) in cio
   and qeth.
 
 - QDIO interrupts and error handling fixes and improvements, more
   refactoring changes.
 
 - Align ioremap() with generic code.
 
 - Accept requests without the prefetch bit set in vfio-ccw.
 
 - Enable path handling via two new regions in vfio-ccw.
 
 - Other small fixes and improvements all over the code.
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Merge tag 's390-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add support for multi-function devices in pci code.

 - Enable PF-VF linking for architectures using the pdev->no_vf_scan
   flag (currently just s390).

 - Add reipl from NVMe support.

 - Get rid of critical section cleanup in entry.S.

 - Refactor PNSO CHSC (perform network subchannel operation) in cio and
   qeth.

 - QDIO interrupts and error handling fixes and improvements, more
   refactoring changes.

 - Align ioremap() with generic code.

 - Accept requests without the prefetch bit set in vfio-ccw.

 - Enable path handling via two new regions in vfio-ccw.

 - Other small fixes and improvements all over the code.

* tag 's390-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (52 commits)
  vfio-ccw: make vfio_ccw_regops variables declarations static
  vfio-ccw: Add trace for CRW event
  vfio-ccw: Wire up the CRW irq and CRW region
  vfio-ccw: Introduce a new CRW region
  vfio-ccw: Refactor IRQ handlers
  vfio-ccw: Introduce a new schib region
  vfio-ccw: Refactor the unregister of the async regions
  vfio-ccw: Register a chp_event callback for vfio-ccw
  vfio-ccw: Introduce new helper functions to free/destroy regions
  vfio-ccw: document possible errors
  vfio-ccw: Enable transparent CCW IPL from DASD
  s390/pci: Log new handle in clp_disable_fh()
  s390/cio, s390/qeth: cleanup PNSO CHSC
  s390/qdio: remove q->first_to_kick
  s390/qdio: fix up qdio_start_irq() kerneldoc
  s390: remove critical section cleanup from entry.S
  s390: add machine check SIGP
  s390/pci: ioremap() align with generic code
  s390/ap: introduce new ap function ap_get_qdev()
  Documentation/s390: Update / remove developerWorks web links
  ...
2020-06-08 12:05:31 -07:00
Linus Torvalds 9fb4c5250f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching
Pull livepatching updates from Jiri Kosina:

 - simplifications and improvements for issues Peter Ziljstra found
   during his previous work on W^X cleanups.

   This allows us to remove livepatch arch-specific .klp.arch sections
   and add proper support for jump labels in patched code.

   Also, this patchset removes the last module_disable_ro() usage in the
   tree.

   Patches from Josh Poimboeuf and Peter Zijlstra

 - a few other minor cleanups

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
  MAINTAINERS: add lib/livepatch to LIVE PATCHING
  livepatch: add arch-specific headers to MAINTAINERS
  livepatch: Make klp_apply_object_relocs static
  MAINTAINERS: adjust to livepatch .klp.arch removal
  module: Make module_enable_ro() static again
  x86/module: Use text_mutex in apply_relocate_add()
  module: Remove module_disable_ro()
  livepatch: Remove module_disable_ro() usage
  x86/module: Use text_poke() for late relocations
  s390/module: Use s390_kernel_write() for late relocations
  s390: Change s390_kernel_write() return type to match memcpy()
  livepatch: Prevent module-specific KLP rela sections from referencing vmlinux symbols
  livepatch: Remove .klp.arch
  livepatch: Apply vmlinux-specific KLP relocations early
  livepatch: Disallow vmlinux.ko
2020-06-04 11:13:03 -07:00
Linus Torvalds cb8e59cc87 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
    Augusto von Dentz.

 2) Add GSO partial support to igc, from Sasha Neftin.

 3) Several cleanups and improvements to r8169 from Heiner Kallweit.

 4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
    device self-test. From Andrew Lunn.

 5) Start moving away from custom driver versions, use the globally
    defined kernel version instead, from Leon Romanovsky.

 6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.

 7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.

 8) Add sriov and vf support to hinic, from Luo bin.

 9) Support Media Redundancy Protocol (MRP) in the bridging code, from
    Horatiu Vultur.

10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.

11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
    Dubroca. Also add ipv6 support for espintcp.

12) Lots of ReST conversions of the networking documentation, from Mauro
    Carvalho Chehab.

13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
    from Doug Berger.

14) Allow to dump cgroup id and filter by it in inet_diag code, from
    Dmitry Yakunin.

15) Add infrastructure to export netlink attribute policies to
    userspace, from Johannes Berg.

16) Several optimizations to sch_fq scheduler, from Eric Dumazet.

17) Fallback to the default qdisc if qdisc init fails because otherwise
    a packet scheduler init failure will make a device inoperative. From
    Jesper Dangaard Brouer.

18) Several RISCV bpf jit optimizations, from Luke Nelson.

19) Correct the return type of the ->ndo_start_xmit() method in several
    drivers, it's netdev_tx_t but many drivers were using
    'int'. From Yunjian Wang.

20) Add an ethtool interface for PHY master/slave config, from Oleksij
    Rempel.

21) Add BPF iterators, from Yonghang Song.

22) Add cable test infrastructure, including ethool interfaces, from
    Andrew Lunn. Marvell PHY driver is the first to support this
    facility.

23) Remove zero-length arrays all over, from Gustavo A. R. Silva.

24) Calculate and maintain an explicit frame size in XDP, from Jesper
    Dangaard Brouer.

25) Add CAP_BPF, from Alexei Starovoitov.

26) Support terse dumps in the packet scheduler, from Vlad Buslov.

27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.

28) Add devm_register_netdev(), from Bartosz Golaszewski.

29) Minimize qdisc resets, from Cong Wang.

30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
    eliminate set_fs/get_fs calls. From Christoph Hellwig.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
  selftests: net: ip_defrag: ignore EPERM
  net_failover: fixed rollback in net_failover_open()
  Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
  Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
  vmxnet3: allow rx flow hash ops only when rss is enabled
  hinic: add set_channels ethtool_ops support
  selftests/bpf: Add a default $(CXX) value
  tools/bpf: Don't use $(COMPILE.c)
  bpf, selftests: Use bpf_probe_read_kernel
  s390/bpf: Use bcr 0,%0 as tail call nop filler
  s390/bpf: Maintain 8-byte stack alignment
  selftests/bpf: Fix verifier test
  selftests/bpf: Fix sample_cnt shared between two threads
  bpf, selftests: Adapt cls_redirect to call csum_level helper
  bpf: Add csum_level helper for fixing up csum levels
  bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
  sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
  crypto/chtls: IPv6 support for inline TLS
  Crypto/chcr: Fixes a coccinile check error
  Crypto/chcr: Fixes compilations warnings
  ...
2020-06-03 16:27:18 -07:00
Linus Torvalds 94709049fb Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:
 "A few little subsystems and a start of a lot of MM patches.

  Subsystems affected by this patch series: squashfs, ocfs2, parisc,
  vfs. With mm subsystems: slab-generic, slub, debug, pagecache, gup,
  swap, memcg, pagemap, memory-failure, vmalloc, kasan"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
  kasan: move kasan_report() into report.c
  mm/mm_init.c: report kasan-tag information stored in page->flags
  ubsan: entirely disable alignment checks under UBSAN_TRAP
  kasan: fix clang compilation warning due to stack protector
  x86/mm: remove vmalloc faulting
  mm: remove vmalloc_sync_(un)mappings()
  x86/mm/32: implement arch_sync_kernel_mappings()
  x86/mm/64: implement arch_sync_kernel_mappings()
  mm/ioremap: track which page-table levels were modified
  mm/vmalloc: track which page-table levels were modified
  mm: add functions to track page directory modifications
  s390: use __vmalloc_node in stack_alloc
  powerpc: use __vmalloc_node in alloc_vm_stack
  arm64: use __vmalloc_node in arch_alloc_vmap_stack
  mm: remove vmalloc_user_node_flags
  mm: switch the test_vmalloc module to use __vmalloc_node
  mm: remove __vmalloc_node_flags_caller
  mm: remove both instances of __vmalloc_node_flags
  mm: remove the prot argument to __vmalloc_node
  mm: remove the pgprot argument to __vmalloc
  ...
2020-06-02 12:21:36 -07:00
Christoph Hellwig b200f5b58c s390: use __vmalloc_node in stack_alloc
stack_alloc can use a slightly higher level vmalloc function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-30-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02 10:59:11 -07:00
Linus Torvalds f359287765 Merge branch 'from-miklos' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "Assorted patches from Miklos.

  An interesting part here is /proc/mounts stuff..."

The "/proc/mounts stuff" is using a cursor for keeeping the location
data while traversing the mount listing.

Also probably worth noting is the addition of faccessat2(), which takes
an additional set of flags to specify how the lookup is done
(AT_EACCESS, AT_SYMLINK_NOFOLLOW, AT_EMPTY_PATH).

* 'from-miklos' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: add faccessat2 syscall
  vfs: don't parse "silent" option
  vfs: don't parse "posixacl" option
  vfs: don't parse forbidden flags
  statx: add mount_root
  statx: add mount ID
  statx: don't clear STATX_ATIME on SB_RDONLY
  uapi: deprecate STATX_ALL
  utimensat: AT_EMPTY_PATH support
  vfs: split out access_override_creds()
  proc/mounts: add cursor
  aio: fix async fsync creds
  vfs: allow unprivileged whiteout creation
2020-06-01 16:44:06 -07:00
Sven Schnelle 0b0ed657fe s390: remove critical section cleanup from entry.S
The current code is rather complex and caused a lot of subtle
and hard to debug bugs in the past. Simplify the code by calling
the system_call handler with interrupts disabled, save
machine state, and re-enable them later.

This requires significant changes to the machine check handling code
as well. When the machine check interrupt arrived while being in kernel
mode the new code will signal pending machine checks with a SIGP external
call. When userspace was interrupted, the handler will switch to the
kernel stack and directly execute s390_handle_mcck().

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-28 12:21:54 +02:00
Sven Schnelle 11886c199d s390: add machine check SIGP
This will be used with the upcoming entry.S changes to signal
that there's a machine check pending that cannot be handled in
the Machine check handler itself.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-28 12:21:42 +02:00
David S. Miller 13209a8f73 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The MSCC bug fix in 'net' had to be slightly adjusted because the
register accesses are done slightly differently in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-24 13:47:27 -07:00
David Hildenbrand 4765600fc7 s390: simplify memory notifier for protecting kdump crash kernel area
Assume we have a crashkernel area of 256MB reserved:

root@vm0:~# cat /proc/iomem
00000000-6fffffff : System RAM
  0f258000-0fcfffff : Kernel code
  0fd00000-101d10e3 : Kernel data
  105b3000-1068dfff : Kernel bss
70000000-7fffffff : Crash kernel

This exactly corresponds to memory block 7 (memory block size is 256MB).
Trying to offline that memory block results in:

root@vm0:~# echo "offline" > /sys/devices/system/memory/memory7/state
-bash: echo: write error: Device or resource busy

[  128.458762] page:000003d081c00000 refcount:1 mapcount:0 mapping:00000000d01cecd4 index:0x0
[  128.458773] flags: 0x1ffff00000001000(reserved)
[  128.458781] raw: 1ffff00000001000 000003d081c00008 000003d081c00008 0000000000000000
[  128.458781] raw: 0000000000000000 0000000000000000 ffffffff00000001 0000000000000000
[  128.458783] page dumped because: unmovable page

The craskernel area is marked reserved in the bootmem allocator. This
results in the memmap getting initialized (refcount=1, PG_reserved), but
the pages are never freed to the page allocator.

So these pages look like allocated pages that are unmovable (esp.
PG_reserved), and therefore, memory offlining fails early, when trying to
isolate the page range.

We only have to care about the exchange area, make that clear.

Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Philipp Rudo <prudo@linux.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@kernel.org>
Link: https://lore.kernel.org/r/20200424083904.8587-1-david@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-20 10:22:51 +02:00
YueHaibing 55d7b4b829 s390: Remove two unused inline functions
commit 657480d9c0 ("s390: support KPROBES_ON_FTRACE")
left behind this, remove it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Sven Schnelle <svens@linux.ibm.com>
Link: https://lore.kernel.org/r/20200508140724.11324-1-yuehaibing@huawei.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-20 10:22:49 +02:00
Gerald Schaefer 4c1cbcbd6c s390/kaslr: add support for R_390_JMP_SLOT relocation type
With certain kernel configurations, the R_390_JMP_SLOT relocation type
might be generated, which is not expected by the KASLR relocation code,
and the kernel stops with the message "Unknown relocation type".

This was found with a zfcpdump kernel config, where CONFIG_MODULES=n
and CONFIG_VFIO=n. In that case, symbol_get() is used on undefined
__weak symbols in virt/kvm/vfio.c, which results in the generation
of R_390_JMP_SLOT relocation types.

Fix this by handling R_390_JMP_SLOT similar to R_390_GLOB_DAT.

Fixes: 805bc0bc23 ("s390/kernel: build a relocatable kernel")
Cc: <stable@vger.kernel.org> # v5.2+
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-20 10:13:27 +02:00
Philipp Rudo 70b690547d s390/kexec_file: fix initrd location for kdump kernel
initrd_start must not point at the location the initrd is loaded into
the crashkernel memory but at the location it will be after the
crashkernel memory is swapped with the memory at 0.

Fixes: ee337f5469 ("s390/kexec_file: Add crash support to image loader")
Reported-by: Lianbo Jiang <lijiang@redhat.com>
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Tested-by: Lianbo Jiang <lijiang@redhat.com>
Link: https://lore.kernel.org/r/20200512193956.15ae3f23@laptop2-ibm.local
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-14 23:21:37 +02:00
Miklos Szeredi c8ffd8bcdd vfs: add faccessat2 syscall
POSIX defines faccessat() as having a fourth "flags" argument, while the
linux syscall doesn't have it.  Glibc tries to emulate AT_EACCESS and
AT_SYMLINK_NOFOLLOW, but AT_EACCESS emulation is broken.

Add a new faccessat(2) syscall with the added flags argument and implement
both flags.

The value of AT_EACCESS is defined in glibc headers to be the same as
AT_REMOVEDIR.  Use this value for the kernel interface as well, together
with the explanatory comment.

Also add AT_EMPTY_PATH support, which is not documented by POSIX, but can
be useful and is trivial to implement.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-05-14 16:44:25 +02:00
Peter Zijlstra be2422612a s390/module: Use s390_kernel_write() for late relocations
Because of late module patching, a livepatch module needs to be able to
apply some of its relocations well after it has been loaded.  Instead of
playing games with module_{dis,en}able_ro(), use existing text poking
mechanisms to apply relocations after module loading.

So far only x86, s390 and Power have HAVE_LIVEPATCH but only the first
two also have STRICT_MODULE_RWX.

This will allow removal of the last module_disable_ro() usage in
livepatch.  The ultimate goal is to completely disallow making
executable mappings writable.

[ jpoimboe: Split up patches.  Use mod state to determine whether
	    memcpy() can be used.  Test and add fixes. ]

Cc: linux-s390@vger.kernel.org
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> # s390
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2020-05-08 00:12:43 +02:00
David S. Miller 3793faad7b Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts were all overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06 22:10:13 -07:00
Jason J. Herne 23a457b8d5 s390: nvme reipl
Populate sysfs and structs with reipl entries for nvme ipl type.
This allows specifying a target nvme device when rebooting/reipling.

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-06 15:19:35 +02:00
Jason J. Herne 3737e8ee4f s390: nvme ipl
Recognize IPL Block's Ipl Type of "nvme". Populate related structs and sysfs
entries.

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-06 15:19:35 +02:00
Masahiro Yamada 0ba577802b s390: ptrace: hard-code "s390x" instead of UTS_MACHINE
s390 uses the UTS_MACHINE defined arch/s390/Makefile as follows:

  UTS_MACHINE     := s390x

We do not need to pass the fixed string from the command line.
Hard-code user_regset_view::name, like many other architectures do.

Link: https://lkml.kernel.org/r/20200413013113.8529-1-masahiroy@kernel.org
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-06 14:59:20 +02:00
Christoph Hellwig 32927393dc sysctl: pass kernel pointers to ->proc_handler
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from  userspace in common code.  This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.

As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-27 02:07:40 -04:00
Claudio Imbrenda 673deb0beb s390/protvirt: fix compilation issue
The kernel fails to compile with CONFIG_PROTECTED_VIRTUALIZATION_GUEST
set but CONFIG_KVM unset.

This patch fixes the issue by making the needed variable always available.

Link: https://lkml.kernel.org/r/20200423120114.2027410-1-imbrenda@linux.ibm.com
Fixes: a0f60f8431 ("s390/protvirt: Add sysfs firmware interface for Ultravisor information")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Philipp Rudo <prudo@linux.ibm.com>
Suggested-by: Philipp Rudo <prudo@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-25 10:17:24 +02:00
Philipp Rudo 8ebf6da9db s390/ftrace: fix potential crashes when switching tracers
Switching tracers include instruction patching. To prevent that a
instruction is patched while it's read the instruction patching is done
in stop_machine 'context'. This also means that any function called
during stop_machine must not be traced. Thus add 'notrace' to all
functions called within stop_machine.

Fixes: 1ec2772e0c ("s390/diag: add a statistic for diagnose calls")
Fixes: 38f2c691a4 ("s390: improve wait logic of stop_machine")
Fixes: 4ecf0a43e7 ("processor: get rid of cpu_relax_yield")
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-22 16:20:55 +02:00
Linus Torvalds ad0bf4eb91 s390 updates for the 5.7 merge window
- Update maintainers. Niklas Schnelle takes over zpci and Vineeth Vijayan
   common io code.
 
 - Extend cpuinfo to include topology information.
 
 - Add new extended counters for IBM z15 and sampling buffer allocation
   rework in perf code.
 
 - Add control over zeroing out memory during system restart.
 
 - CCA protected key block version 2 support and other fixes/improvements
   in crypto code.
 
 - Convert to new fallthrough; annotations.
 
 - Replace zero-length arrays with flexible-arrays.
 
 - QDIO debugfs and other small improvements.
 
 - Drop 2-level paging support optimization for compat tasks. Varios
   mm cleanups.
 
 - Remove broken and unused hibernate / power management support.
 
 - Remove fake numa support which does not bring any benefits.
 
 - Exclude offline CPUs from CPU topology masks to be more consistent
   with other architectures.
 
 - Prevent last branching instruction address leaking to userspace.
 
 - Other small various fixes and improvements all over the code.
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Merge tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Update maintainers. Niklas Schnelle takes over zpci and Vineeth
   Vijayan common io code.

 - Extend cpuinfo to include topology information.

 - Add new extended counters for IBM z15 and sampling buffer allocation
   rework in perf code.

 - Add control over zeroing out memory during system restart.

 - CCA protected key block version 2 support and other
   fixes/improvements in crypto code.

 - Convert to new fallthrough; annotations.

 - Replace zero-length arrays with flexible-arrays.

 - QDIO debugfs and other small improvements.

 - Drop 2-level paging support optimization for compat tasks. Varios mm
   cleanups.

 - Remove broken and unused hibernate / power management support.

 - Remove fake numa support which does not bring any benefits.

 - Exclude offline CPUs from CPU topology masks to be more consistent
   with other architectures.

 - Prevent last branching instruction address leaking to userspace.

 - Other small various fixes and improvements all over the code.

* tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (57 commits)
  s390/mm: cleanup init_new_context() callback
  s390/mm: cleanup virtual memory constants usage
  s390/mm: remove page table downgrade support
  s390/qdio: set qdio_irq->cdev at allocation time
  s390/qdio: remove unused function declarations
  s390/ccwgroup: remove pm support
  s390/ap: remove power management code from ap bus and drivers
  s390/zcrypt: use kvmalloc instead of kmalloc for 256k alloc
  s390/mm: cleanup arch_get_unmapped_area() and friends
  s390/ism: remove pm support
  s390/cio: use fallthrough;
  s390/vfio: use fallthrough;
  s390/zcrypt: use fallthrough;
  s390: use fallthrough;
  s390/cpum_sf: Fix wrong page count in error message
  s390/diag: fix display of diagnose call statistics
  s390/ap: Remove ap device suspend and resume callbacks
  s390/pci: Improve handling of unset UID
  s390/pci: Fix zpci_alloc_domain() over allocation
  s390/qdio: pass ISC as parameter to chsc_sadc()
  ...
2020-04-04 09:45:50 -07:00
Linus Torvalds ff2ae607c6 SPDX patches for 5.7-rc1.
Here are 3 SPDX patches for 5.7-rc1.
 
 One fixes up the SPDX tag for a single driver, while the other two go
 through the tree and add SPDX tags for all of the .gitignore files as
 needed.
 
 Nothing too complex, but you will get a merge conflict with your current
 tree, that should be trivial to handle (one file modified by two things,
 one file deleted.)
 
 All 3 of these have been in linux-next for a while, with no reported
 issues other than the merge conflict.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

Pull SPDX updates from Greg KH:
 "Here are three SPDX patches for 5.7-rc1.

  One fixes up the SPDX tag for a single driver, while the other two go
  through the tree and add SPDX tags for all of the .gitignore files as
  needed.

  Nothing too complex, but you will get a merge conflict with your
  current tree, that should be trivial to handle (one file modified by
  two things, one file deleted.)

  All three of these have been in linux-next for a while, with no
  reported issues other than the merge conflict"

* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  ASoC: MT6660: make spdxcheck.py happy
  .gitignore: add SPDX License Identifier
  .gitignore: remove too obvious comments
2020-04-03 13:12:26 -07:00
Linus Torvalds 8c1b724ddb ARM:
* GICv4.1 support
 * 32bit host removal
 
 PPC:
 * secure (encrypted) using under the Protected Execution Framework
 ultravisor
 
 s390:
 * allow disabling GISA (hardware interrupt injection) and protected
 VMs/ultravisor support.
 
 x86:
 * New dirty bitmap flag that sets all bits in the bitmap when dirty
 page logging is enabled; this is faster because it doesn't require bulk
 modification of the page tables.
 * Initial work on making nested SVM event injection more similar to VMX,
 and less buggy.
 * Various cleanups to MMU code (though the big ones and related
 optimizations were delayed to 5.8).  Instead of using cr3 in function
 names which occasionally means eptp, KVM too has standardized on "pgd".
 * A large refactoring of CPUID features, which now use an array that
 parallels the core x86_features.
 * Some removal of pointer chasing from kvm_x86_ops, which will also be
 switched to static calls as soon as they are available.
 * New Tigerlake CPUID features.
 * More bugfixes, optimizations and cleanups.
 
 Generic:
 * selftests: cleanups, new MMU notifier stress test, steal-time test
 * CSV output for kvm_stat.
 
 KVM/MIPS has been broken since 5.5, it does not compile due to a patch committed
 by MIPS maintainers.  I had already prepared a fix, but the MIPS maintainers
 prefer to fix it in generic code rather than KVM so they are taking care of it.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:
   - GICv4.1 support

   - 32bit host removal

  PPC:
   - secure (encrypted) using under the Protected Execution Framework
     ultravisor

  s390:
   - allow disabling GISA (hardware interrupt injection) and protected
     VMs/ultravisor support.

  x86:
   - New dirty bitmap flag that sets all bits in the bitmap when dirty
     page logging is enabled; this is faster because it doesn't require
     bulk modification of the page tables.

   - Initial work on making nested SVM event injection more similar to
     VMX, and less buggy.

   - Various cleanups to MMU code (though the big ones and related
     optimizations were delayed to 5.8). Instead of using cr3 in
     function names which occasionally means eptp, KVM too has
     standardized on "pgd".

   - A large refactoring of CPUID features, which now use an array that
     parallels the core x86_features.

   - Some removal of pointer chasing from kvm_x86_ops, which will also
     be switched to static calls as soon as they are available.

   - New Tigerlake CPUID features.

   - More bugfixes, optimizations and cleanups.

  Generic:
   - selftests: cleanups, new MMU notifier stress test, steal-time test

   - CSV output for kvm_stat"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (277 commits)
  x86/kvm: fix a missing-prototypes "vmread_error"
  KVM: x86: Fix BUILD_BUG() in __cpuid_entry_get_reg() w/ CONFIG_UBSAN=y
  KVM: VMX: Add a trampoline to fix VMREAD error handling
  KVM: SVM: Annotate svm_x86_ops as __initdata
  KVM: VMX: Annotate vmx_x86_ops as __initdata
  KVM: x86: Drop __exit from kvm_x86_ops' hardware_unsetup()
  KVM: x86: Copy kvm_x86_ops by value to eliminate layer of indirection
  KVM: x86: Set kvm_x86_ops only after ->hardware_setup() completes
  KVM: VMX: Configure runtime hooks using vmx_x86_ops
  KVM: VMX: Move hardware_setup() definition below vmx_x86_ops
  KVM: x86: Move init-only kvm_x86_ops to separate struct
  KVM: Pass kvm_init()'s opaque param to additional arch funcs
  s390/gmap: return proper error code on ksm unsharing
  KVM: selftests: Fix cosmetic copy-paste error in vm_mem_region_move()
  KVM: Fix out of range accesses to memslots
  KVM: X86: Micro-optimize IPI fastpath delay
  KVM: X86: Delay read msr data iff writes ICR MSR
  KVM: PPC: Book3S HV: Add a capability for enabling secure guests
  KVM: arm64: GICv4.1: Expose HW-based SGIs in debugfs
  KVM: arm64: GICv4.1: Allow non-trapping WFI when using HW SGIs
  ...
2020-04-02 15:13:15 -07:00
Joe Perches 2c7749b905 s390: use fallthrough;
Convert the various uses of fallthrough comments to fallthrough;

Done via script
Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe.com/

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-25 12:39:37 +01:00
Thomas Richter 4141b6a5e9 s390/cpum_sf: Fix wrong page count in error message
When perf record -e SF_CYCLES_BASIC_DIAG runs with very high
frequency, the samples arrive faster than the perf process can
save them to file. Eventually, for longer running processes, this
leads to the siutation where the trace buffers allocated by perf
slowly fills up. At one point the auxiliary trace buffer is full
and  the CPU Measurement sampling facility is turned off. Furthermore
a warning is printed to the kernel log buffer:

cpum_sf: The AUX buffer with 0 pages for the diagnostic-sampling
	mode is full

The number of allocated pages for the auxiliary trace buffer is shown
as zero pages. That is wrong.

Fix this by saving the number of allocated pages before entering the
work loop in the interrupt handler. When the interrupt handler processes
the samples, it may detect the buffer full condition and stop sampling,
reducing the buffer size to zero.
Print the correct value in the error message:

cpum_sf: The AUX buffer with 256 pages for the diagnostic-sampling
	mode is full

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-25 12:39:37 +01:00
Michael Mueller 6c7c851f1b s390/diag: fix display of diagnose call statistics
Show the full diag statistic table and not just parts of it.

The issue surfaced in a KVM guest with a number of vcpus
defined smaller than NR_DIAG_STAT.

Fixes: 1ec2772e0c ("s390/diag: add a statistic for diagnose calls")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-25 12:39:37 +01:00
Masahiro Yamada d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Heiko Carstens 394216275c s390: remove broken hibernate / power management support
Hibernation is known to be broken for many years on s390. Given that
there aren't any real use cases, remove the code instead of spending
time to fix and maintain it.

Without hibernate support it doesn't make too much sense to keep power
management support; therefore remove it completely.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 13:41:55 +01:00
Alexander Gordeev 1b648dfd54 s390/cpuinfo: do not skip info for CPUs without MHz feature
In the past there were no per-CPU information in /proc/cpuinfo
other than CPU frequency. Hence, for machines without CPU MHz
feature there were nothing to show. Now CPU topology and IDs
still could be shown, so do not skip this information from the
output.

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
[heiko.carstens@de.ibm.com: moved comparison]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 13:41:55 +01:00
Alexander Gordeev 872f271038 s390/cpuinfo: fix wrong output when CPU0 is offline
/proc/cpuinfo should not print information about CPU 0 when it is offline.

Fixes: 281eaa8cb6 ("s390/cpuinfo: simplify locking and skip offline cpus early")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
[heiko.carstens@de.ibm.com: shortened commit message]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 13:41:54 +01:00
Alexander Gordeev 2db52dc353 s390/cpuinfo: show number of online CPUs within a package
Show number of online CPUs within a package (which is
the socket in case of s390). For what it worth, present
that value as "siblings" field - just like x86 does.

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 13:41:54 +01:00
Alexander Gordeev 959684978d s390/cpuinfo: show number of online cores
Show number of cores that run at least one SMT thread

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 13:41:54 +01:00
Gerald Schaefer 1a2ae03b19 s390/ipl: add support to control memory clearing for FCP and CCW re-IPL
Re-IPL for both CCW and FCP is currently done by using diag 308 with the
"Load Clear" subcode, which means that all memory will be cleared.
This can increase re-IPL duration considerably on very large machines.

For CCW devices, there is also a "Load Normal" subcode that was only used
for dump kernels so far. For FCP devices, a similar "Load Normal" subcode
was introduced with z14. The "Load Normal" diag 308 subcode allows to
re-IPL without clearing memory.

This patch adds a new "clear" sysfs attribute to /sys/firmware/reipl for
both the ccw and fcp subdirectories, which can be set to either "0" or "1"
to disable or enable re-IPL with memory clearing. The default value is "0",
which disables memory clearing.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 13:41:54 +01:00
Alexander Gordeev 52aeda7acc s390/topology: remove offline CPUs from CPU topology masks
The CPU topology masks on s390 contain also bits of CPUs which
are offline. Currently this is already a problem, since common
code scheduler expects e.g. cpu_smt_mask() to reflect reality.

This update changes the described behaviour and s390 starts to
behave like all other architectures.

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 13:41:54 +01:00
Alexander Gordeev cd8e702f0d s390/numa: remove redundant cpus_with_topology variable
Variable cpus_with_topology is a leftover that became
unneeded once the fake NUMA support has been removed.

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 13:41:53 +01:00
Alexander Gordeev 42d211a1ae s390/cpuinfo: show processor physical address
Show CPU physical address as reported by STAP instruction

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23 13:41:53 +01:00
Nayna Jain 9e2b4be377 ima: add a new CONFIG for loading arch-specific policies
Every time a new architecture defines the IMA architecture specific
functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA
include file needs to be updated. To avoid this "noise", this patch
defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing
the different architectures to select it.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Philipp Rudo <prudo@linux.ibm.com> (s390)
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-03-12 07:43:57 -04:00
Heiko Carstens 1d49688d2b s390/traps: mark test_monitor_call __init
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-11 14:18:44 +01:00
Heiko Carstens 76fb118083 s390/irq: make init_ext_interrupts static
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-11 14:18:44 +01:00
afzal mohammed 8719b6d29d s390/irq: replace setup_irq() by request_irq()
request_irq() is preferred over setup_irq(). Invocations of setup_irq()
occur after memory allocators are ready.

Per tglx[1], setup_irq() existed in olden days when allocators were not
ready by the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

[1] https://lkml.kernel.org/r/alpine.DEB.2.20.1710191609480.1971@nanos

Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Message-Id: <20200304005049.5291-1-afzal.mohd.ma@gmail.com>
[heiko.carstens@de.ibm.com: replace pr_err with panic]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-11 14:18:44 +01:00
Alexander Gordeev fb83510295 s390/cpuinfo: add system topology information
This update adjusts /proc/cpuinfo format to meet some user level
programs expectations. It also makes the layout consistent with
x86 where CPU topology is presented as blocks of key-value pairs.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-10 15:16:26 +01:00
Sven Schnelle 0b38b5e1d0 s390: prevent leaking kernel address in BEAR
When userspace executes a syscall or gets interrupted,
BEAR contains a kernel address when returning to userspace.
This make it pretty easy to figure out where the kernel is
mapped even with KASLR enabled. To fix this, add lpswe to
lowcore and always execute it there, so userspace sees only
the lowcore address of lpswe. For this we have to extend
both critical_cleanup and the SWITCH_ASYNC macro to also check
for lpswe addresses in lowcore.

Fixes: b2d24b97b2 ("s390/kernel: add support for kernel address space layout randomization (KASLR)")
Cc: <stable@vger.kernel.org> # v5.2+
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-10 15:16:25 +01:00
Thomas Richter d68d5d51dc s390/cpum_cf: Add new extended counters for IBM z15
Add CPU measurement counter facility event description for IBM z15.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-10 15:16:25 +01:00
Janosch Frank a0f60f8431 s390/protvirt: Add sysfs firmware interface for Ultravisor information
That information, e.g. the maximum number of guests or installed
Ultravisor facilities, is interesting for QEMU, Libvirt and
administrators.

Let's provide an easily parsable API to get that information.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:44:40 +01:00
Vasily Gorbik 084ea4d611 s390/mm: add (non)secure page access exceptions handlers
Add exceptions handlers performing transparent transition of non-secure
pages to secure (import) upon guest access and secure pages to
non-secure (export) upon hypervisor access.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
[frankja@linux.ibm.com: adding checks for failures]
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
[imbrenda@linux.ibm.com:  adding a check for gmap fault]
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:44:40 +01:00
Claudio Imbrenda 214d9bbcd3 s390/mm: provide memory management functions for protected KVM guests
This provides the basic ultravisor calls and page table handling to cope
with secure guests:
- provide arch_make_page_accessible
- make pages accessible after unmapping of secure guests
- provide the ultravisor commands convert to/from secure
- provide the ultravisor commands pin/unpin shared
- provide callbacks to make pages secure (inacccessible)
 - we check for the expected pin count to only make pages secure if the
   host is not accessing them
 - we fence hugetlbfs for secure pages
- add missing radix-tree include into gmap.h

The basic idea is that a page can have 3 states: secure, normal or
shared. The hypervisor can call into a firmware function called
ultravisor that allows to change the state of a page: convert from/to
secure. The convert from secure will encrypt the page and make it
available to the host and host I/O. The convert to secure will remove
the host capability to access this page.
The design is that on convert to secure we will wait until writeback and
page refs are indicating no host usage. At the same time the convert
from secure (export to host) will be called in common code when the
refcount or the writeback bit is already set. This avoids races between
convert from and to secure.

Then there is also the concept of shared pages. Those are kind of secure
where the host can still access those pages. We need to be notified when
the guest "unshares" such a page, basically doing a convert to secure by
then. There is a call "pin shared page" that we use instead of convert
from secure when possible.

We do use PG_arch_1 as an optimization to minimize the convert from
secure/pin shared.

Several comments have been added in the code to explain the logic in
the relevant places.

Co-developed-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Signed-off-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:44:40 +01:00
Vasily Gorbik 29d37e5b82 s390/protvirt: add ultravisor initialization
Before being able to host protected virtual machines, donate some of
the memory to the ultravisor. Besides that the ultravisor might impose
addressing limitations for memory used to back protected VM storage. Treat
that limit as protected virtualization host's virtual memory limit.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:44:40 +01:00
Vasily Gorbik ecdc5d842b s390/protvirt: introduce host side setup
Add "prot_virt" command line option which controls if the kernel
protected VMs support is enabled at early boot time. This has to be
done early, because it needs large amounts of memory and will disable
some features like STP time sync for the lpar.

Extend ultravisor info definitions and expose it via uv_info struct
filled in during startup.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:44:40 +01:00
Heiko Carstens 701dc81e74 s390/mm: remove fake numa support
It turned out that fake numa support is rather useless on s390, since
there are no scenarios where there is any performance or other benefit
when used.

However it does provide maintenance cost and breaks from time to time.
Therefore remove it.

CONFIG_NUMA is still supported with a very small backend and only one
node. This way userspace applications which require NUMA interfaces
continue to work.

Note that NODES_SHIFT is set to 1 (= 2 nodes) instead of 0 (= 1 node),
since there is quite a bit of kernel code which assumes that more than
one node is possible if CONFIG_NUMA is enabled.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-02-27 16:02:21 +01:00
Thomas Richter 0d6f1693f2 s390/cpum_sf: Rework sampling buffer allocation
Adjust sampling buffer allocation depending on
frequency and correct comments. Investigation on the
interrupt handler revealed that almost always one interupt
services one SDB, even when running with the maximum frequency
of 100000. Very rarely there have been 2 SBD serviced per
interrupt.

Therefore reduce the number of SBD per CPU. Each SDB is one
page in size. The new formula results in
freq:4000	n_sdb:32	new:16
freq:10000	n_sdb:80	new:16
freq:20000	n_sdb:159	new:17
freq:40000	n_sdb:318	new:19
freq:50000	n_sdb:397	new:20
freq:62500	n_sdb:497	new:22
freq:83333	n_sdb:662	new:24
freq:100000	n_sdb:794	new:25

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-02-17 18:04:15 +01:00
Linus Torvalds cfb4b571e8 s390 updates for the 5.6 merge window #2
- Add KPROBES_ON_FTRACE support.
 
 - Add EP11 AES secure keys support.
 
 - PAES rework and prerequisites for paes-s390 ciphers selftests.
 
 - Fix page table upgrade for hugetlbfs.
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Merge tag 's390-5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull more s390 updates from Vasily Gorbik:
 "The second round of s390 fixes and features for 5.6:

   - Add KPROBES_ON_FTRACE support

   - Add EP11 AES secure keys support

   - PAES rework and prerequisites for paes-s390 ciphers selftests

   - Fix page table upgrade for hugetlbfs"

* tag 's390-5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/pkey/zcrypt: Support EP11 AES secure keys
  s390/zcrypt: extend EP11 card and queue sysfs attributes
  s390/zcrypt: add new low level ep11 functions support file
  s390/zcrypt: ep11 structs rework, export zcrypt_send_ep11_cprb
  s390/zcrypt: enable card/domain autoselect on ep11 cprbs
  s390/crypto: enable clear key values for paes ciphers
  s390/pkey: Add support for key blob with clear key value
  s390/crypto: Rework on paes implementation
  s390: support KPROBES_ON_FTRACE
  s390/mm: fix dynamic pagetable upgrade for hugetlbfs
2020-02-05 17:33:35 +00:00
Mikhail Zaslonko c65e6815db s390/boot: add dfltcc= kernel command line parameter
Add the new kernel command line parameter 'dfltcc=' to configure s390
zlib hardware support.

Format: { on | off | def_only | inf_only | always }
 on:       s390 zlib hardware support for compression on
           level 1 and decompression (default)
 off:      No s390 zlib hardware support
 def_only: s390 zlib hardware support for deflate
           only (compression on level 1)
 inf_only: s390 zlib hardware support for inflate
           only (decompression)
 always:   Same as 'on' but ignores the selected compression
           level always using hardware support (used for debugging)

Link: http://lkml.kernel.org/r/20200103223334.20669-5-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Cc: Chris Mason <clm@fb.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Eduard Shishkin <edward6@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31 10:30:40 -08:00
Anshuman Khandual 02634a44b8 mm/memblock: define memblock_physmem_add()
On the s390 platform memblock.physmem array is being built by directly
calling into memblock_add_range() which is a low level function not
intended to be used outside of memblock.  Hence lets conditionally add
helper functions for physmem array when HAVE_MEMBLOCK_PHYS_MAP is
enabled.  Also use MAX_NUMNODES instead of 0 as node ID similar to
memblock_add() and memblock_reserve().  Make memblock_add_range() a
static function as it is no longer getting used outside of memblock.

Link: http://lkml.kernel.org/r/1578283835-21969-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Collin Walling <walling@linux.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31 10:30:38 -08:00
Sven Schnelle 657480d9c0 s390: support KPROBES_ON_FTRACE
Instead of using our own kprobes-on-ftrace handling convert the
code to support KPROBES_ON_FTRACE.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-01-30 13:07:55 +01:00
Linus Torvalds 83fa805bcb threads-v5.6
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Merge tag 'threads-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull thread management updates from Christian Brauner:
 "Sargun Dhillon over the last cycle has worked on the pidfd_getfd()
  syscall.

  This syscall allows for the retrieval of file descriptors of a process
  based on its pidfd. A task needs to have ptrace_may_access()
  permissions with PTRACE_MODE_ATTACH_REALCREDS (suggested by Oleg and
  Andy) on the target.

  One of the main use-cases is in combination with seccomp's user
  notification feature. As a reminder, seccomp's user notification
  feature was made available in v5.0. It allows a task to retrieve a
  file descriptor for its seccomp filter. The file descriptor is usually
  handed of to a more privileged supervising process. The supervisor can
  then listen for syscall events caught by the seccomp filter of the
  supervisee and perform actions in lieu of the supervisee, usually
  emulating syscalls. pidfd_getfd() is needed to expand its uses.

  There are currently two major users that wait on pidfd_getfd() and one
  future user:

   - Netflix, Sargun said, is working on a service mesh where users
     should be able to connect to a dns-based VIP. When a user connects
     to e.g. 1.2.3.4:80 that runs e.g. service "foo" they will be
     redirected to an envoy process. This service mesh uses seccomp user
     notifications and pidfd to intercept all connect calls and instead
     of connecting them to 1.2.3.4:80 connects them to e.g.
     127.0.0.1:8080.

   - LXD uses the seccomp notifier heavily to intercept and emulate
     mknod() and mount() syscalls for unprivileged containers/processes.
     With pidfd_getfd() more uses-cases e.g. bridging socket connections
     will be possible.

   - The patchset has also seen some interest from the browser corner.
     Right now, Firefox is using a SECCOMP_RET_TRAP sandbox managed by a
     broker process. In the future glibc will start blocking all signals
     during dlopen() rendering this type of sandbox impossible. Hence,
     in the future Firefox will switch to a seccomp-user-nofication
     based sandbox which also makes use of file descriptor retrieval.
     The thread for this can be found at
     https://sourceware.org/ml/libc-alpha/2019-12/msg00079.html

  With pidfd_getfd() it is e.g. possible to bridge socket connections
  for the supervisee (binding to a privileged port) and taking actions
  on file descriptors on behalf of the supervisee in general.

  Sargun's first version was using an ioctl on pidfds but various people
  pushed for it to be a proper syscall which he duely implemented as
  well over various review cycles. Selftests are of course included.
  I've also added instructions how to deal with merge conflicts below.

  There's also a small fix coming from the kernel mentee project to
  correctly annotate struct sighand_struct with __rcu to fix various
  sparse warnings. We've received a few more such fixes and even though
  they are mostly trivial I've decided to postpone them until after -rc1
  since they came in rather late and I don't want to risk introducing
  build warnings.

  Finally, there's a new prctl() command PR_{G,S}ET_IO_FLUSHER which is
  needed to avoid allocation recursions triggerable by storage drivers
  that have userspace parts that run in the IO path (e.g. dm-multipath,
  iscsi, etc). These allocation recursions deadlock the device.

  The new prctl() allows such privileged userspace components to avoid
  allocation recursions by setting the PF_MEMALLOC_NOIO and
  PF_LESS_THROTTLE flags. The patch carries the necessary acks from the
  relevant maintainers and is routed here as part of prctl()
  thread-management."

* tag 'threads-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  prctl: PR_{G,S}ET_IO_FLUSHER to support controlling memory reclaim
  sched.h: Annotate sighand_struct with __rcu
  test: Add test for pidfd getfd
  arch: wire up pidfd_getfd syscall
  pid: Implement pidfd_getfd syscall
  vfs, fdtable: Add fget_task helper
2020-01-29 19:38:34 -08:00
Linus Torvalds 6aee4badd8 Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull openat2 support from Al Viro:
 "This is the openat2() series from Aleksa Sarai.

  I'm afraid that the rest of namei stuff will have to wait - it got
  zero review the last time I'd posted #work.namei, and there had been a
  leak in the posted series I'd caught only last weekend. I was going to
  repost it on Monday, but the window opened and the odds of getting any
  review during that... Oh, well.

  Anyway, openat2 part should be ready; that _did_ get sane amount of
  review and public testing, so here it comes"

From Aleksa's description of the series:
 "For a very long time, extending openat(2) with new features has been
  incredibly frustrating. This stems from the fact that openat(2) is
  possibly the most famous counter-example to the mantra "don't silently
  accept garbage from userspace" -- it doesn't check whether unknown
  flags are present[1].

  This means that (generally) the addition of new flags to openat(2) has
  been fraught with backwards-compatibility issues (O_TMPFILE has to be
  defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
  kernels gave errors, since it's insecure to silently ignore the
  flag[2]). All new security-related flags therefore have a tough road
  to being added to openat(2).

  Furthermore, the need for some sort of control over VFS's path
  resolution (to avoid malicious paths resulting in inadvertent
  breakouts) has been a very long-standing desire of many userspace
  applications.

  This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset
  (which was a variant of David Drysdale's O_BENEATH patchset[4] which
  was a spin-off of the Capsicum project[5]) with a few additions and
  changes made based on the previous discussion within [6] as well as
  others I felt were useful.

  In line with the conclusions of the original discussion of
  AT_NO_JUMPS, the flag has been split up into separate flags. However,
  instead of being an openat(2) flag it is provided through a new
  syscall openat2(2) which provides several other improvements to the
  openat(2) interface (see the patch description for more details). The
  following new LOOKUP_* flags are added:

  LOOKUP_NO_XDEV:

     Blocks all mountpoint crossings (upwards, downwards, or through
     absolute links). Absolute pathnames alone in openat(2) do not
     trigger this. Magic-link traversal which implies a vfsmount jump is
     also blocked (though magic-link jumps on the same vfsmount are
     permitted).

  LOOKUP_NO_MAGICLINKS:

     Blocks resolution through /proc/$pid/fd-style links. This is done
     by blocking the usage of nd_jump_link() during resolution in a
     filesystem. The term "magic-links" is used to match with the only
     reference to these links in Documentation/, but I'm happy to change
     the name.

     It should be noted that this is different to the scope of
     ~LOOKUP_FOLLOW in that it applies to all path components. However,
     you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it
     will *not* fail (assuming that no parent component was a
     magic-link), and you will have an fd for the magic-link.

     In order to correctly detect magic-links, the introduction of a new
     LOOKUP_MAGICLINK_JUMPED state flag was required.

  LOOKUP_BENEATH:

     Disallows escapes to outside the starting dirfd's
     tree, using techniques such as ".." or absolute links. Absolute
     paths in openat(2) are also disallowed.

     Conceptually this flag is to ensure you "stay below" a certain
     point in the filesystem tree -- but this requires some additional
     to protect against various races that would allow escape using
     "..".

     Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it
     can trivially beam you around the filesystem (breaking the
     protection). In future, there might be similar safety checks done
     as in LOOKUP_IN_ROOT, but that requires more discussion.

  In addition, two new flags are added that expand on the above ideas:

  LOOKUP_NO_SYMLINKS:

     Does what it says on the tin. No symlink resolution is allowed at
     all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this
     can still be used with NOFOLLOW to open an fd for the symlink as
     long as no parent path had a symlink component.

  LOOKUP_IN_ROOT:

     This is an extension of LOOKUP_BENEATH that, rather than blocking
     attempts to move past the root, forces all such movements to be
     scoped to the starting point. This provides chroot(2)-like
     protection but without the cost of a chroot(2) for each filesystem
     operation, as well as being safe against race attacks that
     chroot(2) is not.

     If a race is detected (as with LOOKUP_BENEATH) then an error is
     generated, and similar to LOOKUP_BENEATH it is not permitted to
     cross magic-links with LOOKUP_IN_ROOT.

     The primary need for this is from container runtimes, which
     currently need to do symlink scoping in userspace[7] when opening
     paths in a potentially malicious container.

     There is a long list of CVEs that could have bene mitigated by
     having RESOLVE_THIS_ROOT (such as CVE-2017-1002101,
     CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a
     few).

  In order to make all of the above more usable, I'm working on
  libpathrs[8] which is a C-friendly library for safe path resolution.
  It features a userspace-emulated backend if the kernel doesn't support
  openat2(2). Hopefully we can get userspace to switch to using it, and
  thus get openat2(2) support for free once it's ready.

  Future work would include implementing things like
  RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow
  programs to be sure they don't hit DoSes though stale NFS handles)"

* 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Documentation: path-lookup: include new LOOKUP flags
  selftests: add openat2(2) selftests
  open: introduce openat2(2) syscall
  namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution
  namei: LOOKUP_IN_ROOT: chroot-like scoped resolution
  namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution
  namei: LOOKUP_NO_XDEV: block mountpoint crossing
  namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution
  namei: LOOKUP_NO_SYMLINKS: block symlink resolution
  namei: allow set_root() to produce errors
  namei: allow nd_jump_link() to produce errors
  nsfs: clean-up ns_get_path() signature to return int
  namei: only return -ECHILD from follow_dotdot_rcu()
2020-01-29 11:20:24 -08:00
Linus Torvalds ca9b5b6283 TTY/Serial driver updates for 5.6-rc1
Here are the big set of tty and serial driver updates for 5.6-rc1
 
 Included in here are:
 	- dummy_con cleanups (touches lots of arch code)
 	- sysrq logic cleanups (touches lots of serial drivers)
 	- samsung driver fixes (wasn't really being built)
 	- conmakeshash move to tty subdir out of scripts
 	- lots of small tty/serial driver updates
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here are the big set of tty and serial driver updates for 5.6-rc1

  Included in here are:
   - dummy_con cleanups (touches lots of arch code)
   - sysrq logic cleanups (touches lots of serial drivers)
   - samsung driver fixes (wasn't really being built)
   - conmakeshash move to tty subdir out of scripts
   - lots of small tty/serial driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
  tty: n_hdlc: Use flexible-array member and struct_size() helper
  tty: baudrate: SPARC supports few more baud rates
  tty: baudrate: Synchronise baud_table[] and baud_bits[]
  tty: serial: meson_uart: Add support for kernel debugger
  serial: imx: fix a race condition in receive path
  serial: 8250_bcm2835aux: Document struct bcm2835aux_data
  serial: 8250_bcm2835aux: Use generic remapping code
  serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
  serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
  serial_core: Remove unused member in uart_port
  vt: Correct comment documenting do_take_over_console()
  vt: Delete comment referencing non-existent unbind_con_driver()
  arch/xtensa/setup: Drop dummy_con initialization
  arch/x86/setup: Drop dummy_con initialization
  arch/unicore32/setup: Drop dummy_con initialization
  arch/sparc/setup: Drop dummy_con initialization
  arch/sh/setup: Drop dummy_con initialization
  arch/s390/setup: Drop dummy_con initialization
  ...
2020-01-29 10:13:27 -08:00
Linus Torvalds 740eaf7d4d s390 updates for the 5.6 merge window
- Add clang 10 build support.
 
 - Fix BUG() implementation to contain precise bug address, which is
   relevant for kprobes.
 
 - Make ftraced function appear in a stacktrace.
 
 - Minor perf improvements and refactoring.
 
 - Possible deadlock and recovery fixes in pci code.
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Merge tag 's390-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add clang 10 build support.

 - Fix BUG() implementation to contain precise bug address, which is
   relevant for kprobes.

 - Make ftraced function appear in a stacktrace.

 - Minor perf improvements and refactoring.

 - Possible deadlock and recovery fixes in pci code.

* tag 's390-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: fix __EMIT_BUG() macro
  s390/ftrace: generate traced function stack frame
  s390: adjust -mpacked-stack support check for clang 10
  s390/jump_label: use "i" constraint for clang
  s390/cpum_sf: Use DIV_ROUND_UP
  s390/cpum_sf: Use kzalloc and minor changes
  s390/cpum_sf: Convert debug trace to common layout
  s390/pci: Fix possible deadlock in recover_store()
  s390/pci: Recover handle in clp_set_pci_fn()
2020-01-28 18:43:08 -08:00
Linus Torvalds c677124e63 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "These were the main changes in this cycle:

   - More -rt motivated separation of CONFIG_PREEMPT and
     CONFIG_PREEMPTION.

   - Add more low level scheduling topology sanity checks and warnings
     to filter out nonsensical topologies that break scheduling.

   - Extend uclamp constraints to influence wakeup CPU placement

   - Make the RT scheduler more aware of asymmetric topologies and CPU
     capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y

   - Make idle CPU selection more consistent

   - Various fixes, smaller cleanups, updates and enhancements - please
     see the git log for details"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
  sched/fair: Define sched_idle_cpu() only for SMP configurations
  sched/topology: Assert non-NUMA topology masks don't (partially) overlap
  idle: fix spelling mistake "iterrupts" -> "interrupts"
  sched/fair: Remove redundant call to cpufreq_update_util()
  sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled
  sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP
  sched/fair: calculate delta runnable load only when it's needed
  sched/cputime: move rq parameter in irqtime_account_process_tick
  stop_machine: Make stop_cpus() static
  sched/debug: Reset watchdog on all CPUs while processing sysrq-t
  sched/core: Fix size of rq::uclamp initialization
  sched/uclamp: Fix a bug in propagating uclamp value in new cgroups
  sched/fair: Load balance aggressively for SCHED_IDLE CPUs
  sched/fair : Improve update_sd_pick_busiest for spare capacity case
  watchdog: Remove soft_lockup_hrtimer_cnt and related code
  sched/rt: Make RT capacity-aware
  sched/fair: Make EAS wakeup placement consider uclamp restrictions
  sched/fair: Make task_fits_capacity() consider uclamp restrictions
  sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with()
  sched/uclamp: Make uclamp util helpers use and return UL values
  ...
2020-01-28 10:07:09 -08:00
Sven Schnelle 17248ea036 s390: fix __EMIT_BUG() macro
Setting a kprobe on getname_flags() failed:

$ echo 'p:tmr1 getname_flags +0(%r2):ustring' > kprobe_events
-bash: echo: write error: Invalid argument

Debugging the kprobes code showed that the address of
getname_flags() is contained in the __bug_table. Kprobes
doesn't allow to set probes at BUG() locations.

$ objdump -j  __bug_table -x build/fs/namei.o
[..]
0000000000000108 R_390_PC32        .text+0x00000000000075a8
000000000000010c R_390_PC32        .L223+0x0000000000000004

I was expecting getname_flags() to start with a BUG(), but:

7598:       e3 20 10 00 00 04       lg      %r2,0(%r1)
759e:       c0 f4 00 00 00 00       jg      759e <putname+0x7e>
75a0: R_390_PLT32DBL    kmem_cache_free+0x2
75a4:       a7 f4 00 01             j       75a6 <putname+0x86>

00000000000075a8 <getname_flags>:
75a8:       c0 04 00 00 00 00       brcl    0,75a8 <getname_flags>
75ae:       eb 6f f0 48 00 24       stmg    %r6,%r15,72(%r15)
75b4:       b9 04 00 ef             lgr     %r14,%r15
75b8:       e3 f0 ff a8 ff 71       lay     %r15,-88(%r15)

So the BUG() is actually the last opcode of the previous function.
Fix this by switching to using the MONITOR CALL (MC) instruction,
and set the entry in __bug_table to the beginning of that MC.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-01-22 13:05:35 +01:00
Vasily Gorbik 45f7a0da60 s390/ftrace: generate traced function stack frame
Currently backtrace from ftraced function does not contain ftraced
function itself. e.g. for "path_openat":

arch_stack_walk+0x15c/0x2d8
stack_trace_save+0x50/0x68
stack_trace_call+0x15e/0x3d8
ftrace_graph_caller+0x0/0x1c <-- ftrace code
do_filp_open+0x7c/0xe8 <-- ftraced function caller
do_open_execat+0x76/0x1b8
open_exec+0x52/0x78
load_elf_binary+0x180/0x1160
search_binary_handler+0x8e/0x288
load_script+0x2a8/0x2b8
search_binary_handler+0x8e/0x288
__do_execve_file.isra.39+0x6fa/0xb40
__s390x_sys_execve+0x56/0x68
system_call+0xdc/0x2d8

Ftraced function is expected in the backtrace by ftrace kselftests, which
are now failing. It would also be nice to have it for clarity reasons.

"ftrace_caller" itself is called without stack frame allocated for it
and does not store its caller (ftraced function). Instead it simply
allocates a stack frame for "ftrace_trace_function" and sets backchain
to point to ftraced function stack frame (which contains ftraced function
caller in saved r14).

To fix this issue make "ftrace_caller" allocate a stack frame
for itself just to store ftraced function for the stack unwinder.
As a result backtrace looks like the following:

arch_stack_walk+0x15c/0x2d8
stack_trace_save+0x50/0x68
stack_trace_call+0x15e/0x3d8
ftrace_graph_caller+0x0/0x1c <-- ftrace code
path_openat+0x6/0xd60  <-- ftraced function
do_filp_open+0x7c/0xe8 <-- ftraced function caller
do_open_execat+0x76/0x1b8
open_exec+0x52/0x78
load_elf_binary+0x180/0x1160
search_binary_handler+0x8e/0x288
load_script+0x2a8/0x2b8
search_binary_handler+0x8e/0x288
__do_execve_file.isra.39+0x6fa/0xb40
__s390x_sys_execve+0x56/0x68
system_call+0xdc/0x2d8

Reported-by: Sven Schnelle <sven.schnelle@ibm.com>
Tested-by: Sven Schnelle <sven.schnelle@ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-01-22 13:05:35 +01:00
Thomas Richter ee09c91480 s390/cpum_sf: Use DIV_ROUND_UP
Use macro DIV_ROUND_UP() for calculation of number of SDBT
SDBT pages required for index pages. This macro is already
used throughout the file.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-01-22 13:05:35 +01:00
Thomas Richter 32dab6828c s390/cpum_sf: Use kzalloc and minor changes
Use kzalloc() to allocate auxiliary buffer structure initialized
with all zeroes to avoid random value in trace output.

Avoid double access to SBD hardware flags.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-01-22 13:05:34 +01:00
Thomas Richter ee5c4ccfd5 s390/cpum_sf: Convert debug trace to common layout
Convert debug traces to print the head/alert/empty marks
consistently as decimal numbers. Add some trace statements
to enable easier debugging during auxiliary tracing.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-01-22 13:05:34 +01:00
Aleksa Sarai fddb5d430a open: introduce openat2(2) syscall
/* Background. */
For a very long time, extending openat(2) with new features has been
incredibly frustrating. This stems from the fact that openat(2) is
possibly the most famous counter-example to the mantra "don't silently
accept garbage from userspace" -- it doesn't check whether unknown flags
are present[1].

This means that (generally) the addition of new flags to openat(2) has
been fraught with backwards-compatibility issues (O_TMPFILE has to be
defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
kernels gave errors, since it's insecure to silently ignore the
flag[2]). All new security-related flags therefore have a tough road to
being added to openat(2).

Userspace also has a hard time figuring out whether a particular flag is
supported on a particular kernel. While it is now possible with
contemporary kernels (thanks to [3]), older kernels will expose unknown
flag bits through fcntl(F_GETFL). Giving a clear -EINVAL during
openat(2) time matches modern syscall designs and is far more
fool-proof.

In addition, the newly-added path resolution restriction LOOKUP flags
(which we would like to expose to user-space) don't feel related to the
pre-existing O_* flag set -- they affect all components of path lookup.
We'd therefore like to add a new flag argument.

Adding a new syscall allows us to finally fix the flag-ignoring problem,
and we can make it extensible enough so that we will hopefully never
need an openat3(2).

/* Syscall Prototype. */
  /*
   * open_how is an extensible structure (similar in interface to
   * clone3(2) or sched_setattr(2)). The size parameter must be set to
   * sizeof(struct open_how), to allow for future extensions. All future
   * extensions will be appended to open_how, with their zero value
   * acting as a no-op default.
   */
  struct open_how { /* ... */ };

  int openat2(int dfd, const char *pathname,
              struct open_how *how, size_t size);

/* Description. */
The initial version of 'struct open_how' contains the following fields:

  flags
    Used to specify openat(2)-style flags. However, any unknown flag
    bits or otherwise incorrect flag combinations (like O_PATH|O_RDWR)
    will result in -EINVAL. In addition, this field is 64-bits wide to
    allow for more O_ flags than currently permitted with openat(2).

  mode
    The file mode for O_CREAT or O_TMPFILE.

    Must be set to zero if flags does not contain O_CREAT or O_TMPFILE.

  resolve
    Restrict path resolution (in contrast to O_* flags they affect all
    path components). The current set of flags are as follows (at the
    moment, all of the RESOLVE_ flags are implemented as just passing
    the corresponding LOOKUP_ flag).

    RESOLVE_NO_XDEV       => LOOKUP_NO_XDEV
    RESOLVE_NO_SYMLINKS   => LOOKUP_NO_SYMLINKS
    RESOLVE_NO_MAGICLINKS => LOOKUP_NO_MAGICLINKS
    RESOLVE_BENEATH       => LOOKUP_BENEATH
    RESOLVE_IN_ROOT       => LOOKUP_IN_ROOT

open_how does not contain an embedded size field, because it is of
little benefit (userspace can figure out the kernel open_how size at
runtime fairly easily without it). It also only contains u64s (even
though ->mode arguably should be a u16) to avoid having padding fields
which are never used in the future.

Note that as a result of the new how->flags handling, O_PATH|O_TMPFILE
is no longer permitted for openat(2). As far as I can tell, this has
always been a bug and appears to not be used by userspace (and I've not
seen any problems on my machines by disallowing it). If it turns out
this breaks something, we can special-case it and only permit it for
openat(2) but not openat2(2).

After input from Florian Weimer, the new open_how and flag definitions
are inside a separate header from uapi/linux/fcntl.h, to avoid problems
that glibc has with importing that header.

/* Testing. */
In a follow-up patch there are over 200 selftests which ensure that this
syscall has the correct semantics and will correctly handle several
attack scenarios.

In addition, I've written a userspace library[4] which provides
convenient wrappers around openat2(RESOLVE_IN_ROOT) (this is necessary
because no other syscalls support RESOLVE_IN_ROOT, and thus lots of care
must be taken when using RESOLVE_IN_ROOT'd file descriptors with other
syscalls). During the development of this patch, I've run numerous
verification tests using libpathrs (showing that the API is reasonably
usable by userspace).

/* Future Work. */
Additional RESOLVE_ flags have been suggested during the review period.
These can be easily implemented separately (such as blocking auto-mount
during resolution).

Furthermore, there are some other proposed changes to the openat(2)
interface (the most obvious example is magic-link hardening[5]) which
would be a good opportunity to add a way for userspace to restrict how
O_PATH file descriptors can be re-opened.

Another possible avenue of future work would be some kind of
CHECK_FIELDS[6] flag which causes the kernel to indicate to userspace
which openat2(2) flags and fields are supported by the current kernel
(to avoid userspace having to go through several guesses to figure it
out).

[1]: https://lwn.net/Articles/588444/
[2]: https://lore.kernel.org/lkml/CA+55aFyyxJL1LyXZeBsf2ypriraj5ut1XkNDsunRBqgVjZU_6Q@mail.gmail.com
[3]: commit 629e014bb8 ("fs: completely ignore unknown open flags")
[4]: https://sourceware.org/bugzilla/show_bug.cgi?id=17523
[5]: https://lore.kernel.org/lkml/20190930183316.10190-2-cyphar@cyphar.com/
[6]: https://youtu.be/ggD-eb3yPVs

Suggested-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-01-18 09:19:18 -05:00
Arvind Sankar c5ff734cf6 arch/s390/setup: Drop dummy_con initialization
con_init in tty/vt.c will now set conswitchp to dummy_con if it's unset.
Drop it from arch setup code.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20191218214506.49252-20-nivedita@alum.mit.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14 15:29:18 +01:00
Sargun Dhillon 9a2cef09c8
arch: wire up pidfd_getfd syscall
This wires up the pidfd_getfd syscall for all architectures.

Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20200107175927.4558-4-sargun@sargun.me
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-01-13 21:49:47 +01:00
Philipp Rudo 40260b01d0 s390/setup: Fix secure ipl message
The new machine loader on z15 always creates an IPL Report block and
thus sets the IPL_PL_FLAG_IPLSR even when secure boot is disabled. This
causes the wrong message being printed at boot. Fix this by checking for
IPL_PL_FLAG_SIPL instead.

Fixes: 9641b8cc73 ("s390/ipl: read IPL report at early boot")
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-01-09 16:59:18 +01:00
Ingo Molnar 1e5f8a3085 Linux 5.5-rc3
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Merge tag 'v5.5-rc3' into sched/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25 10:41:37 +01:00
Vasily Gorbik b4adfe5591 s390/ftrace: save traced function caller
A typical backtrace acquired from ftraced function currently looks like
the following (e.g. for "path_openat"):

arch_stack_walk+0x15c/0x2d8
stack_trace_save+0x50/0x68
stack_trace_call+0x15a/0x3b8
ftrace_graph_caller+0x0/0x1c
0x3e0007e3c98 <- ftraced function caller (should be do_filp_open+0x7c/0xe8)
do_open_execat+0x70/0x1b8
__do_execve_file.isra.0+0x7d8/0x860
__s390x_sys_execve+0x56/0x68
system_call+0xdc/0x2d8

Note random "0x3e0007e3c98" stack value as ftraced function caller. This
value causes either imprecise unwinder result or unwinding failure.
That "0x3e0007e3c98" comes from r14 of ftraced function stack frame, which
it haven't had a chance to initialize since the very first instruction
calls ftrace code ("ftrace_caller"). (ftraced function might never
save r14 as well). Nevertheless according to s390 ABI any function
is called with stack frame allocated for it and r14 contains return
address. "ftrace_caller" itself is called with "brasl %r0,ftrace_caller".
So, to fix this issue simply always save traced function caller onto
ftraced function stack frame.

Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-12-18 23:29:26 +01:00
Vasily Gorbik eef06cbf67 s390/unwind: stop gracefully at user mode pt_regs in irq stack
Consider reaching user mode pt_regs at the bottom of irq stack graceful
unwinder termination. This is the case when irq/mcck/ext interrupt arrives
while in user mode.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-12-18 23:29:26 +01:00
Heiko Carstens 1b68ac8678 s390: remove last diag 0x44 caller
diag 0x44 is a voluntary undirected yield of a virtual CPU. This has
caused a lot of performance issues in the past.

There is only one caller left, and that one is only executed if diag
0x9c (directed yield) is not present. Given that all hypervisors
implement diag 0x9c anyway, remove the last diag 0x44 to avoid that
more callers will be added.

Worst case that could happen now, if diag 0x9c is not present, is that
a virtual CPU would loop a bit instead of giving its time slice up.

diag 0x44 statistics in debugfs are kept and will always be zero, so
that user space can tell that there are no calls.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-12-11 19:53:24 +01:00
Thomas Richter 0539ad0b22 s390/cpum_sf: Avoid SBD overflow condition in irq handler
The s390 CPU Measurement sampling facility has an overflow condition
which fires when all entries in a SBD are used.
The measurement alert interrupt is triggered and reads out all samples
in this SDB. It then tests the successor SDB, if this SBD is not full,
the interrupt handler does not read any samples at all from this SDB
The design waits for the hardware to fill this SBD and then trigger
another meassurement alert interrupt.

This scheme works nicely until
an perf_event_overflow() function call discards the sample due to
a too high sampling rate.
The interrupt handler has logic to read out a partially filled SDB
when the perf event overflow condition in linux common code is met.
This causes the CPUM sampling measurement hardware and the PMU
device driver to operate on the same SBD's trailer entry.
This should not happen.

This can be seen here using this trace:
   cpumsf_pmu_add: tear:0xb5286000
   hw_perf_event_update: sdbt 0xb5286000 full 1 over 0 flush_all:0
   hw_perf_event_update: sdbt 0xb5286008 full 0 over 0 flush_all:0
        above shows 1. interrupt
   hw_perf_event_update: sdbt 0xb5286008 full 1 over 0 flush_all:0
   hw_perf_event_update: sdbt 0xb5286008 full 0 over 0 flush_all:0
        above shows 2. interrupt
	... this goes on fine until...
   hw_perf_event_update: sdbt 0xb5286068 full 1 over 0 flush_all:0
   perf_push_sample1: overflow
      one or more samples read from the IRQ handler are rejected by
      perf_event_overflow() and the IRQ handler advances to the next SDB
      and modifies the trailer entry of a partially filled SDB.
   hw_perf_event_update: sdbt 0xb5286070 full 0 over 0 flush_all:1
      timestamp: 14:32:52.519953

Next time the IRQ handler is called for this SDB the trailer entry shows
an overflow count of 19 missed entries.
   hw_perf_event_update: sdbt 0xb5286070 full 1 over 19 flush_all:1
      timestamp: 14:32:52.970058

Remove access to a follow on SDB when event overflow happened.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-12-11 19:53:24 +01:00
Thomas Richter 39d4a501a9 s390/cpum_sf: Adjust sampling interval to avoid hitting sample limits
Function perf_event_ever_overflow() and perf_event_account_interrupt()
are called every time samples are processed by the interrupt handler.
However function perf_event_account_interrupt() has checks to avoid being
flooded with interrupts (more then 1000 samples are received per
task_tick).  Samples are then dropped and a PERF_RECORD_THROTTLED is
added to the perf data. The perf subsystem limit calculation is:

    maximum sample frequency := 100000 --> 1 samples per 10 us
    task_tick = 10ms = 10000us --> 1000 samples per task_tick

The work flow is

measurement_alert() uses SDBT head and each SBDT points to 511
 SDB pages, each with 126 sample entries. After processing 8 SBDs
 and for each valid sample calling:

     perf_event_overflow()
       perf_event_account_interrupts()

there is a considerable amount of samples being dropped, especially when
the sample frequency is very high and near the 100000 limit.

To avoid the high amount of samples being dropped near the end of a
task_tick time frame, increment the sampling interval in case of
dropped events. The CPU Measurement sampling facility on the s390
supports only intervals, specifiing how many CPU cycles have to be
executed before a sample is generated. Increase the interval when the
samples being generated hit the task_tick limit.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-12-11 19:53:23 +01:00
Thomas Gleixner fa68645305 sched/rt, s390: Use CONFIG_PREEMPTION
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Switch the preemption and entry code over to use CONFIG_PREEMPTION. Add
PREEMPT_RT output to die().

[bigeasy: +Kconfig, dumpstack.c]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Link: https://lore.kernel.org/r/20191015191821.11479-18-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-08 14:37:35 +01:00
Linus Torvalds 01d1dff646 s390 updates for the 5.5 merge window #2
- Make stack unwinder reliable and suitable for livepatching. Add unwinder
   testing module.
 
 - Fixes for CALL_ON_STACK helper used for stack switching.
 
 - Fix unwinding from bpf code.
 
 - Fix getcpu and remove compat support in vdso code.
 
 - Fix address space control registers initialization.
 
 - Save KASLR offset for early dumps.
 
 - Handle new FILTERED_BY_HYPERVISOR reply code in crypto code.
 
 - Minor perf code cleanup and potential memory leak fix.
 
 - Add couple of error messages for corner cases during PCI device
   creation.
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Merge tag 's390-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull more s390 updates from Vasily Gorbik:

 - Make stack unwinder reliable and suitable for livepatching. Add
   unwinder testing module.

 - Fixes for CALL_ON_STACK helper used for stack switching.

 - Fix unwinding from bpf code.

 - Fix getcpu and remove compat support in vdso code.

 - Fix address space control registers initialization.

 - Save KASLR offset for early dumps.

 - Handle new FILTERED_BY_HYPERVISOR reply code in crypto code.

 - Minor perf code cleanup and potential memory leak fix.

 - Add couple of error messages for corner cases during PCI device
   creation.

* tag 's390-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (33 commits)
  s390: remove compat vdso code
  s390/livepatch: Implement reliable stack tracing for the consistency model
  s390/unwind: add stack pointer alignment sanity checks
  s390/unwind: filter out unreliable bogus %r14
  s390/unwind: start unwinding from reliable state
  s390/test_unwind: add program check context tests
  s390/test_unwind: add irq context tests
  s390/test_unwind: print verbose unwinding results
  s390/test_unwind: add CALL_ON_STACK tests
  s390: fix register clobbering in CALL_ON_STACK
  s390/test_unwind: require that unwinding ended successfully
  s390/unwind: add a test for the internal API
  s390/unwind: always inline get_stack_pointer
  s390/pci: add error message on device number limit
  s390/pci: add error message for UID collision
  s390/cpum_sf: Check for SDBT and SDB consistency
  s390/cpum_sf: Use TEAR_REG macro consistantly
  s390/cpum_sf: Remove unnecessary check for pending SDBs
  s390/cpum_sf: Replace function name in debug statements
  s390/kaslr: store KASLR offset for early dumps
  ...
2019-12-03 12:50:00 -08:00
Heiko Carstens 2115fbf721 s390: remove compat vdso code
Remove compat vdso code, since there is hardly any compat user space
left. Still existing compat user space will have to use system calls
instead.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-12-01 12:48:49 +01:00
Linus Torvalds b94ae8ad9f seccomp updates for v5.5
- implement SECCOMP_USER_NOTIF_FLAG_CONTINUE (Christian Brauner)
 - fixes to selftests (Christian Brauner)
 - remove secure_computing() argument (Christian Brauner)
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Merge tag 'seccomp-v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull seccomp updates from Kees Cook:
 "Mostly this is implementing the new flag SECCOMP_USER_NOTIF_FLAG_CONTINUE,
  but there are cleanups as well.

   - implement SECCOMP_USER_NOTIF_FLAG_CONTINUE (Christian Brauner)

   - fixes to selftests (Christian Brauner)

   - remove secure_computing() argument (Christian Brauner)"

* tag 'seccomp-v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  seccomp: rework define for SECCOMP_USER_NOTIF_FLAG_CONTINUE
  seccomp: fix SECCOMP_USER_NOTIF_FLAG_CONTINUE test
  seccomp: simplify secure_computing()
  seccomp: test SECCOMP_USER_NOTIF_FLAG_CONTINUE
  seccomp: add SECCOMP_USER_NOTIF_FLAG_CONTINUE
  seccomp: avoid overflow in implicit constant conversion
2019-11-30 17:23:16 -08:00
Miroslav Benes aa137a6d30 s390/livepatch: Implement reliable stack tracing for the consistency model
The livepatch consistency model requires reliable stack tracing
architecture support in order to work properly. In order to achieve
this, two main issues have to be solved. First, reliable and consistent
call chain backtracing has to be ensured. Second, the unwinder needs to
be able to detect stack corruptions and return errors.

The "zSeries ELF Application Binary Interface Supplement" says:

  "The stack pointer points to the first word of the lowest allocated
  stack frame. If the "back chain" is implemented this word will point to
  the previously allocated stack frame (towards higher addresses), except
  for the first stack frame, which shall have a back chain of zero (NULL).
  The stack shall grow downwards, in other words towards lower addresses."

"back chain" is optional. GCC option -mbackchain enables it. Quoting
Martin Schwidefsky [1]:

  "The compiler is called with the -mbackchain option, all normal C
  function will store the backchain in the function prologue. All
  functions written in assembler code should do the same, if you find one
  that does not we should fix that. The end result is that a task that
  *voluntarily* called schedule() should have a proper backchain at all
  times.

  Dependent on the use case this may or may not be enough. Asynchronous
  interrupts may stop the CPU at the beginning of a function, if kernel
  preemption is enabled we can end up with a broken backchain.  The
  production kernels for IBM Z are all compiled *without* kernel
  preemption. So yes, we might get away without the objtool support.

  On a side-note, we do have a line item to implement the ORC unwinder for
  the kernel, that includes the objtool support. Once we have that we can
  drop the -mbackchain option for the kernel build. That gives us a nice
  little performance benefit. I hope that the change from backchain to the
  ORC unwinder will not be too hard to implement in the livepatch tools."

Since -mbackchain is enabled by default when the kernel is compiled, the
call chain backtracing should be currently ensured and objtool should
not be necessary for livepatch purposes.

Regarding the second issue, stack corruptions and non-reliable states
have to be recognized by the unwinder. Mainly it means to detect
preemption or page faults, the end of the task stack must be reached,
return addresses must be valid text addresses and hacks like function
graph tracing and kretprobes must be properly detected.

Unwinding a running task's stack is not a problem, because there is a
livepatch requirement that every checked task is blocked, except for the
current task. Due to that, the implementation can be much simpler
compared to the existing non-reliable infrastructure. We can consider a
task's kernel/thread stack only and skip the other stacks.

[1] 20180912121106.31ffa97c@mschwideX1 [not archived on lore.kernel.org]

Link: https://lkml.kernel.org/r/20191106095601.29986-5-mbenes@suse.cz
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:48 +01:00
Miroslav Benes be2d11b2a1 s390/unwind: add stack pointer alignment sanity checks
ABI requires SP to be aligned 8 bytes, report unwinding error otherwise.

Link: https://lkml.kernel.org/r/20191106095601.29986-5-mbenes@suse.cz
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:48 +01:00
Vasily Gorbik bf018ee644 s390/unwind: filter out unreliable bogus %r14
Currently unwinder unconditionally returns %r14 from the first frame
pointed by %r15 from pt_regs. A task could be interrupted when a function
already allocated this frame (if it needs it) for its callees or to
store local variables. In that case this frame would contain random
values from stack or values stored there by a callee. As we are only
interested in %r14 to get potential return address, skip bogus return
addresses which doesn't belong to kernel text.

This helps to avoid duplicating filtering logic in unwider users, most
of which use unwind_get_return_address() and would choke on bogus 0
address returned by it otherwise.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:48 +01:00
Vasily Gorbik 222ee9087a s390/unwind: start unwinding from reliable state
A comment in arch/s390/include/asm/unwind.h says:
> If 'first_frame' is not zero unwind_start skips unwind frames until it
> reaches the specified stack pointer.
> The end of the unwinding is indicated with unwind_done, this can be true
> right after unwind_start, e.g. with first_frame!=0 that can not be found.
> unwind_next_frame skips to the next frame.
> Once the unwind is completed unwind_error() can be used to check if there
> has been a situation where the unwinder could not correctly understand
> the tasks call chain.

With this change backchain unwinder now comply with behaviour
described. As well as matches orc unwinder implementation.  Now unwinder
starts from reliable state, i.e. __unwind_start own stack frame is
taken or stack frame generated by __switch_to (ksp) - both known to be
valid. In case of pt_regs %r15 is better match for pt_regs psw, than
sometimes random "sp" caller passed.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:48 +01:00
Vasily Gorbik 0610154650 s390/test_unwind: print verbose unwinding results
Add stack name, sp and reliable information into test unwinding
results. Also consider ip outside of kernel text as failure if the
state is reported reliable.

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:48 +01:00
Thomas Richter 247f265fa5 s390/cpum_sf: Check for SDBT and SDB consistency
Each SBDT is located at a 4KB page and contains 512 entries.
Each entry of a SDBT points to a SDB, a 4KB page containing
sampled data. The last entry is a link to another SDBT page.

When an event is created the function sequence executed is:

  __hw_perf_event_init()
  +--> allocate_buffers()
       +--> realloc_sampling_buffers()
	    +---> alloc_sample_data_block()

Both functions realloc_sampling_buffers() and
alloc_sample_data_block() allocate pages and the allocation
can fail. This is handled correctly and all allocated
pages are freed and error -ENOMEM is returned to the
top calling function. Finally the event is not created.

Once the event has been created, the amount of initially
allocated SDBT and SDB can be too low. This is detected
during measurement interrupt handling, where the amount
of lost samples is calculated. If the number of lost samples
is too high considering sampling frequency and already allocated
SBDs, the number of SDBs is enlarged during the next execution
of cpumsf_pmu_enable().

If more SBDs need to be allocated, functions

       realloc_sampling_buffers()
       +---> alloc-sample_data_block()

are called to allocate more pages. Page allocation may fail
and the returned error is ignored. A SDBT and SDB setup
already exists.

However the modified SDBTs and SDBs might end up in a situation
where the first entry of an SDBT does not point to an SDB,
but another SDBT, basicly an SBDT without payload.
This can not be handled by the interrupt handler, where an SDBT
must have at least one entry pointing to an SBD.

Add a check to avoid SDBTs with out payload (SDBs) when enlarging
the buffer setup.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:46 +01:00
Thomas Richter 7dd6b199df s390/cpum_sf: Use TEAR_REG macro consistantly
The macro TEAR_REG() saves the last used SDBT address
in the perf_hw_event structure. This is also done
by function hw_reset_registers() which is a one-liner
and simply uses macro TEAR_REG(). Remove function
hw_reset_registers(), which is only used one time and use
macro TEAR_REG() instead. This macro is used throughout
the code anyway.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:46 +01:00
Thomas Richter c17a7c6ee8 s390/cpum_sf: Remove unnecessary check for pending SDBs
In interrupt handling the function extend_sampling_buffer()
is called after checking for a possibly extension.
This check is not necessary as the called function itself
performs this check again.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:46 +01:00
Thomas Richter 532da3de70 s390/cpum_sf: Replace function name in debug statements
Replace hard coded function names in debug statements
by the "%s ...", __func__ construct suggested by checkpatch.pl
script.  Use consistent debug print format of the form variable
blank value. Also add leading 0x for all hex values.
Print allocated page addresses consistantly as hex numbers
with leading 0x.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:46 +01:00
Gerald Schaefer a9f2f6865d s390/kaslr: store KASLR offset for early dumps
The KASLR offset is added to vmcoreinfo in arch_crash_save_vmcoreinfo(),
so that it can be found by crash when processing kernel dumps.

However, arch_crash_save_vmcoreinfo() is called during a subsys_initcall,
so if the kernel crashes before that, we have no vmcoreinfo and no KASLR
offset.

Fix this by storing the KASLR offset in the lowcore, where the vmcore_info
pointer will be stored, and where it can be found by crash. In order to
make it distinguishable from a real vmcore_info pointer, mark it as uneven
(KASLR offset itself is aligned to THREAD_SIZE).

When arch_crash_save_vmcoreinfo() stores the real vmcore_info pointer in
the lowcore, it overwrites the KASLR offset. At that point, the KASLR
offset is not yet added to vmcoreinfo, so we also need to move the
mem_assign_absolute() behind the vmcoreinfo_append_str().

Fixes: b2d24b97b2 ("s390/kernel: add support for kernel address space layout randomization (KASLR)")
Cc: <stable@vger.kernel.org> # v5.2+
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:45 +01:00
Vasily Gorbik e76e69611e s390/unwind: stop gracefully at task pt_regs
Consider reaching task pt_regs graceful unwinder termination. Task
pt_regs itself never contains a valid state to which a task might return
within the kernel context (user task pt_regs is a special case). Since
we already avoid printing user task pt_regs and in most cases we don't
even bother filling task pt_regs psw and r15 with something reasonable
simply skip task pt_regs altogether. With this change unwind_error() now
accurately represent whether unwinder reached task pt_regs successfully
or failed along the way.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:45 +01:00
Vasily Gorbik cb7948e8c3 s390/head64: correct init_task stack setup
Add missing allocation of pt_regs at the bottom of the stack. This
makes it consistent with other stack setup cases and also what stack
unwinder expects.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:45 +01:00
Vasily Gorbik 97806dfb6f s390/unwind: make reuse_sp default when unwinding pt_regs
Currently unwinder yields 2 entries when pt_regs are met:
sp="address of pt_regs itself" ip=pt_regs->psw
sp=pt_regs->gprs[15] ip="r14 from stack frame pointed by pt_regs->gprs[15]"

And neither of those 2 states (combination of sp and ip) ever happened.

reuse_sp has been introduced by commit a1d863ac3e ("s390/unwind: fix
mixing regs and sp"). reuse_sp=true makes unwinder keen to produce the
following result, when pt_regs are given (as an arg to unwind_start):
sp=pt_regs->gprs[15] ip=pt_regs->psw
sp=pt_regs->gprs[15] ip="r14 from stack frame pointed by pt_regs->gprs[15]"

The first state is an actual state in which a task was when pt_regs were
collected. The second state is marked unreliable and is for debugging
purposes to cover the case when a task has been interrupted in between
stack frame allocation and writing back_chain - in this case r14 might
show an actual caller.

Make unwinder behaviour enabled via reuse_sp=true default and drop the
special case handling.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:45 +01:00
Vasily Gorbik 67f5593419 s390/unwind: report an error if pt_regs are not on stack
If unwinder is looking at pt_regs which is not on stack then something
went wrong and an error has to be reported rather than successful
unwinding termination.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:45 +01:00
Vasily Gorbik 7bcaad1f9f s390: avoid misusing CALL_ON_STACK for task stack setup
CALL_ON_STACK is intended to be used for temporary stack switching with
potential return to the caller.

When CALL_ON_STACK is misused to switch from nodat stack to task stack
back_chain information would later lead stack unwinder from task stack into
(per cpu) nodat stack which is reused for other purposes. This would
yield confusing unwinding result or errors.

To avoid that introduce CALL_ON_STACK_NORETURN to be used instead. It
makes sure that back_chain is zeroed and unwinder finishes gracefully
ending up at task pt_regs.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:45 +01:00
Vasily Gorbik 103b4cca60 s390/unwind: unify task is current checks
Avoid mixture of task == NULL and task == current meaning the same
thing and simply always initialize task with current in unwind_start.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:45 +01:00
Vasily Gorbik 7f28dad395 s390: disable preemption when switching to nodat stack with CALL_ON_STACK
Make sure preemption is disabled when temporary switching to nodat
stack with CALL_ON_STACK helper, because nodat stack is per cpu.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:45 +01:00
Heiko Carstens 5a5525b048 s390/vdso: fix getcpu
getcpu reads the required values for cpu and node with two
instructions. This might lead to an inconsistent result if user space
gets preempted and migrated to a different CPU between the two
instructions.

Fix this by using just a single instruction to read both values at
once.

This is currently rather a theoretical bug, since there is no real
NUMA support available (except for NUMA emulation).

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:44 +01:00
Heiko Carstens a2308c11ec s390/smp,vdso: fix ASCE handling
When a secondary CPU is brought up it must initialize its control
registers. CPU A which triggers that a secondary CPU B is brought up
stores its control register contents into the lowcore of new CPU B,
which then loads these values on startup.

This is problematic in various ways: the control register which
contains the home space ASCE will correctly contain the kernel ASCE;
however control registers for primary and secondary ASCEs are
initialized with whatever values were present in CPU A.

Typically:
- the primary ASCE will contain the user process ASCE of the process
  that triggered onlining of CPU B.
- the secondary ASCE will contain the percpu VDSO ASCE of CPU A.

Due to lazy ASCE handling we may also end up with other combinations.

When then CPU B switches to a different process (!= idle) it will
fixup the primary ASCE. However the problem is that the (wrong) ASCE
from CPU A was loaded into control register 1: as soon as an ASCE is
attached (aka loaded) a CPU is free to generate TLB entries using that
address space.
Even though it is very unlikey that CPU B will actually generate such
entries, this could result in TLB entries of the address space of the
process that ran on CPU A. These entries shouldn't exist at all and
could cause problems later on.

Furthermore the secondary ASCE of CPU B will not be updated correctly.
This means that processes may see wrong results or even crash if they
access VDSO data on CPU B. The correct VDSO ASCE will eventually be
loaded on return to user space as soon as the kernel executed a call
to strnlen_user or an atomic futex operation on CPU B.

Fix both issues by intializing the to be loaded control register
contents with the correct ASCEs and also enforce (re-)loading of the
ASCEs upon first context switch and return to user space.

Fixes: 0aaba41b58 ("s390: remove all code using the access register mode")
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-30 10:52:44 +01:00
Linus Torvalds 77a05940ee Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The biggest changes in this cycle were:

   - Make kcpustat vtime aware (Frederic Weisbecker)

   - Rework the CFS load_balance() logic (Vincent Guittot)

   - Misc cleanups, smaller enhancements, fixes.

  The load-balancing rework is the most intrusive change: it replaces
  the old heuristics that have become less meaningful after the
  introduction of the PELT metrics, with a grounds-up load-balancing
  algorithm.

  As such it's not really an iterative series, but replaces the old
  load-balancing logic with the new one. We hope there are no
  performance regressions left - but statistically it's highly probable
  that there *is* going to be some workload that is hurting from these
  chnages. If so then we'd prefer to have a look at that workload and
  fix its scheduling, instead of reverting the changes"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
  rackmeter: Use vtime aware kcpustat accessor
  leds: Use all-in-one vtime aware kcpustat accessor
  cpufreq: Use vtime aware kcpustat accessors for user time
  procfs: Use all-in-one vtime aware kcpustat accessor
  sched/vtime: Bring up complete kcpustat accessor
  sched/cputime: Support other fields on kcpustat_field()
  sched/cpufreq: Move the cfs_rq_util_change() call to cpufreq_update_util()
  sched/fair: Add comments for group_type and balancing at SD_NUMA level
  sched/fair: Fix rework of find_idlest_group()
  sched/uclamp: Fix overzealous type replacement
  sched/Kconfig: Fix spelling mistake in user-visible help text
  sched/core: Further clarify sched_class::set_next_task()
  sched/fair: Use mul_u32_u32()
  sched/core: Simplify sched_class::pick_next_task()
  sched/core: Optimize pick_next_task()
  sched/core: Make pick_next_task_idle() more consistent
  sched/fair: Better document newidle_balance()
  leds: Use vtime aware kcpustat accessor to fetch CPUTIME_SYSTEM
  cpufreq: Use vtime aware kcpustat accessor to fetch CPUTIME_SYSTEM
  procfs: Use vtime aware kcpustat accessor to fetch CPUTIME_SYSTEM
  ...
2019-11-26 15:23:14 -08:00
Linus Torvalds 1d87200446 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Cross-arch changes to move the linker sections for NOTES and
     EXCEPTION_TABLE into the RO_DATA area, where they belong on most
     architectures. (Kees Cook)

   - Switch the x86 linker fill byte from x90 (NOP) to 0xcc (INT3), to
     trap jumps into the middle of those padding areas instead of
     sliding execution. (Kees Cook)

   - A thorough cleanup of symbol definitions within x86 assembler code.
     The rather randomly named macros got streamlined around a
     (hopefully) straightforward naming scheme:

        SYM_START(name, linkage, align...)
        SYM_END(name, sym_type)

        SYM_FUNC_START(name)
        SYM_FUNC_END(name)

        SYM_CODE_START(name)
        SYM_CODE_END(name)

        SYM_DATA_START(name)
        SYM_DATA_END(name)

     etc - with about three times of these basic primitives with some
     label, local symbol or attribute variant, expressed via postfixes.

     No change in functionality intended. (Jiri Slaby)

   - Misc other changes, cleanups and smaller fixes"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
  x86/entry/64: Remove pointless jump in paranoid_exit
  x86/entry/32: Remove unused resume_userspace label
  x86/build/vdso: Remove meaningless CFLAGS_REMOVE_*.o
  m68k: Convert missed RODATA to RO_DATA
  x86/vmlinux: Use INT3 instead of NOP for linker fill bytes
  x86/mm: Report actual image regions in /proc/iomem
  x86/mm: Report which part of kernel image is freed
  x86/mm: Remove redundant address-of operators on addresses
  xtensa: Move EXCEPTION_TABLE to RO_DATA segment
  powerpc: Move EXCEPTION_TABLE to RO_DATA segment
  parisc: Move EXCEPTION_TABLE to RO_DATA segment
  microblaze: Move EXCEPTION_TABLE to RO_DATA segment
  ia64: Move EXCEPTION_TABLE to RO_DATA segment
  h8300: Move EXCEPTION_TABLE to RO_DATA segment
  c6x: Move EXCEPTION_TABLE to RO_DATA segment
  arm64: Move EXCEPTION_TABLE to RO_DATA segment
  alpha: Move EXCEPTION_TABLE to RO_DATA segment
  x86/vmlinux: Move EXCEPTION_TABLE to RO_DATA segment
  x86/vmlinux: Actually use _etext for the end of the text segment
  vmlinux.lds.h: Allow EXCEPTION_TABLE to live in RO_DATA
  ...
2019-11-26 10:42:40 -08:00
Linus Torvalds ea1f56fa16 s390 updates for the 5.5 merge window
- Adjust PMU device drivers registration to avoid WARN_ON and few other
   perf improvements.
 
 - Enhance tracing in vfio-ccw.
 
 - Few stack unwinder fixes and improvements, convert get_wchan custom
   stack unwinding to generic api usage.
 
 - Fixes for mm helpers issues uncovered with tests validating architecture
   page table helpers.
 
 - Fix noexec bit handling when hardware doesn't support it.
 
 - Fix memleak and unsigned value compared with zero bugs in crypto
   code. Minor code simplification.
 
 - Fix crash during kdump with kasan enabled kernel.
 
 - Switch bug and alternatives from asm to asm_inline to improve inlining
   decisions.
 
 - Use 'depends on cc-option' for MARCH and TUNE options in Kconfig,
   add z13s and z14 ZR1 to TUNE descriptions.
 
 - Minor head64.S simplification.
 
 - Fix physical to logical CPU map for SMT.
 
 - Several cleanups in qdio code.
 
 - Other minor cleanups and fixes all over the code.
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Merge tag 's390-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Adjust PMU device drivers registration to avoid WARN_ON and few other
   perf improvements.

 - Enhance tracing in vfio-ccw.

 - Few stack unwinder fixes and improvements, convert get_wchan custom
   stack unwinding to generic api usage.

 - Fixes for mm helpers issues uncovered with tests validating
   architecture page table helpers.

 - Fix noexec bit handling when hardware doesn't support it.

 - Fix memleak and unsigned value compared with zero bugs in crypto
   code. Minor code simplification.

 - Fix crash during kdump with kasan enabled kernel.

 - Switch bug and alternatives from asm to asm_inline to improve
   inlining decisions.

 - Use 'depends on cc-option' for MARCH and TUNE options in Kconfig, add
   z13s and z14 ZR1 to TUNE descriptions.

 - Minor head64.S simplification.

 - Fix physical to logical CPU map for SMT.

 - Several cleanups in qdio code.

 - Other minor cleanups and fixes all over the code.

* tag 's390-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (41 commits)
  s390/cpumf: Adjust registration of s390 PMU device drivers
  s390/smp: fix physical to logical CPU map for SMT
  s390/early: move access registers setup in C code
  s390/head64: remove unnecessary vdso_per_cpu_data setup
  s390/early: move control registers setup in C code
  s390/kasan: support memcpy_real with TRACE_IRQFLAGS
  s390/crypto: Fix unsigned variable compared with zero
  s390/pkey: use memdup_user() to simplify code
  s390/pkey: fix memory leak within _copy_apqns_from_user()
  s390/disassembler: don't hide instruction addresses
  s390/cpum_sf: Assign error value to err variable
  s390/cpum_sf: Replace function name in debug statements
  s390/cpum_sf: Use consistant debug print format for sampling
  s390/unwind: drop unnecessary code around calling ftrace_graph_ret_addr()
  s390: add error handling to perf_callchain_kernel
  s390: always inline current_stack_pointer()
  s390/mm: add mm_pxd_folded() checks to pxd_free()
  s390/mm: properly clear _PAGE_NOEXEC bit when it is not supported
  s390/mm: simplify page table helpers for large entries
  s390/mm: make pmd/pud_bad() report large entries as bad
  ...
2019-11-25 17:23:53 -08:00
Thomas Richter 6a82e23f45 s390/cpumf: Adjust registration of s390 PMU device drivers
Linux-next commit titled "perf/core: Optimize perf_init_event()"
changed the semantics of PMU device driver registration.
It was done to speed up the lookup/handling of PMU device driver
specific events. It also enforces that only one PMU device
driver will be registered of type PERF_EVENT_RAW.

This change added these line in function perf_pmu_register():

  ...
  +       ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL);
  +       if (ret < 0)
                goto free_pdc;
  +
  +       WARN_ON(type >= 0 && ret != type);

The warn_on generates a message. We have 3 PMU device drivers,
each registered as type PERF_TYPE_RAW.
The cf_diag device driver (arch/s390/kernel/perf_cpumf_cf_diag.c)
always hits the WARN_ON because it is the second PMU device driver
(after sampling device driver arch/s390/kernel/perf_cpumf_sf.c)
which is registered as type 4 (PERF_TYPE_RAW).
So when the sampling device driver is registered, ret has value 4.
When cf_diag device driver is registered with type 4,
ret has value of 5 and WARN_ON fires.

Adjust the PMU device drivers for s390 to support the new
semantics required by perf_pmu_register().

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-20 17:16:01 +01:00
Heiko Carstens 72a81ad9d6 s390/smp: fix physical to logical CPU map for SMT
If an SMT capable system is not IPL'ed from the first CPU the setup of
the physical to logical CPU mapping is broken: the IPL core gets CPU
number 0, but then the next core gets CPU number 1. Correct would be
that all SMT threads of CPU 0 get the subsequent logical CPU numbers.

This is important since a lot of code (like e.g. the CPU topology
code) assumes that CPU maps are setup like this. If the mapping is
broken the system will not IPL due to broken topology masks:

[    1.716341] BUG: arch topology broken
[    1.716342]      the SMT domain not a subset of the MC domain
[    1.716343] BUG: arch topology broken
[    1.716344]      the MC domain not a subset of the BOOK domain

This scenario can usually not happen since LPARs are always IPL'ed
from CPU 0 and also re-IPL is intiated from CPU 0. However older
kernels did initiate re-IPL on an arbitrary CPU. If therefore a re-IPL
from an old kernel into a new kernel is initiated this may lead to
crash.

Fix this by setting up the physical to logical CPU mapping correctly.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-20 12:58:13 +01:00
Vasily Gorbik c231359421 s390/early: move access registers setup in C code
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-20 12:58:13 +01:00
Vasily Gorbik b8ce1fa489 s390/head64: remove unnecessary vdso_per_cpu_data setup
vdso_per_cpu_data lowcore value is only needed for fully functional
exception handlers, which are activated in setup_lowcore_dat_off. The
same function does init vdso_per_cpu_data via vdso_alloc_boot_cpu.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-20 12:58:12 +01:00
Vasily Gorbik c02ee6a16a s390/early: move control registers setup in C code
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-20 12:58:12 +01:00
Ilya Leoshkevich 544f1d62e3 s390/disassembler: don't hide instruction addresses
Due to kptr_restrict, JITted BPF code is now displayed like this:

000000000b6ed1b2: ebdff0800024  stmg    %r13,%r15,128(%r15)
000000004cde2ba0: 41d0f040      la      %r13,64(%r15)
00000000fbad41b0: a7fbffa0      aghi    %r15,-96

Leaking kernel addresses to dmesg is not a concern in this case, because
this happens only when JIT debugging is explicitly activated, which only
root can do.

Use %px in this particular instance, and also to print an instruction
address in show_code and PCREL (e.g. brasl) arguments in print_insn.
While at present functionally equivalent to %016lx, %px is recommended
by Documentation/core-api/printk-formats.rst for such cases.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-12 11:24:10 +01:00
Thomas Richter 72fbcd057f s390/cpum_sf: Assign error value to err variable
When starting the CPU Measurement sampling facility using
qsi() function, this function may return an error value.
This error value is referenced in the else part of the
if statement to dump its value in a debug statement.
Right now this value is always zero because it has not been
assigned a value.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-12 11:24:10 +01:00
Thomas Richter c18388340c s390/cpum_sf: Replace function name in debug statements
Replace hard coded function names in debug statements
by the "%s ...", __func__ construct suggested by checkpatch.pl
script.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-12 11:24:10 +01:00
Thomas Richter d98b5d0728 s390/cpum_sf: Use consistant debug print format for sampling
Use consistant debug print format of the form variable
blank value. Also add leading 0x for all hex values.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-12 11:24:10 +01:00
Ingo Molnar 6d5a763c30 Linux 5.4-rc7
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Merge tag 'v5.4-rc7' into sched/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-11 08:34:59 +01:00
Miroslav Benes c2f2093e14 s390/unwind: drop unnecessary code around calling ftrace_graph_ret_addr()
The current code around calling ftrace_graph_ret_addr() is ifdeffed and
also tests if ftrace redirection is present on stack.
ftrace_graph_ret_addr() however performs the test internally and there
is a version for !CONFIG_FUNCTION_GRAPH_TRACER as well. The unnecessary
code can thus be dropped.

Link: http://lkml.kernel.org/r/20191029143904.24051-2-mbenes@suse.cz
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-05 12:30:15 +01:00
Kees Cook c9174047b4 vmlinux.lds.h: Replace RW_DATA_SECTION with RW_DATA
Rename RW_DATA_SECTION to RW_DATA. (Calling this a "section" is a lie,
since it's multiple sections and section flags cannot be applied to
the macro.)

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # s390
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Will Deacon <will@kernel.org>
Cc: x86-ml <x86@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20191029211351.13243-14-keescook@chromium.org
2019-11-04 15:57:41 +01:00
Kees Cook 93240b3279 vmlinux.lds.h: Replace RO_DATA_SECTION with RO_DATA
Finish renaming RO_DATA_SECTION to RO_DATA. (Calling this a "section"
is a lie, since it's multiple sections and section flags cannot be
applied to the macro.)

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # s390
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Will Deacon <will@kernel.org>
Cc: x86-ml <x86@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20191029211351.13243-13-keescook@chromium.org
2019-11-04 15:56:16 +01:00
Kees Cook eaf937075c vmlinux.lds.h: Move NOTES into RO_DATA
The .notes section should be non-executable read-only data. As such,
move it to the RO_DATA macro instead of being per-architecture defined.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # s390
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Will Deacon <will@kernel.org>
Cc: x86-ml <x86@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20191029211351.13243-11-keescook@chromium.org
2019-11-04 15:34:41 +01:00
Kees Cook fbe6a8e618 vmlinux.lds.h: Move Program Header restoration into NOTES macro
In preparation for moving NOTES into RO_DATA, make the Program Header
assignment restoration be part of the NOTES macro itself.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # s390
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Will Deacon <will@kernel.org>
Cc: x86-ml <x86@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20191029211351.13243-10-keescook@chromium.org
2019-11-04 15:34:39 +01:00
Kees Cook 441110a547 vmlinux.lds.h: Provide EMIT_PT_NOTE to indicate export of .notes
In preparation for moving NOTES into RO_DATA, provide a mechanism for
architectures that want to emit a PT_NOTE Program Header to do so.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # s390
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Will Deacon <will@kernel.org>
Cc: x86-ml <x86@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20191029211351.13243-9-keescook@chromium.org
2019-11-04 15:34:38 +01:00
Kees Cook 6434efbd9a s390: Move RO_DATA into "text" PT_LOAD Program Header
In preparation for moving NOTES into RO_DATA, move RO_DATA back into the
"text" PT_LOAD Program Header, as done with other architectures. The
"data" PT_LOAD now starts with the writable data section.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Will Deacon <will@kernel.org>
Cc: x86-ml <x86@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20191029211351.13243-7-keescook@chromium.org
2019-11-04 15:34:32 +01:00
Heiko Carstens 3d7efa4edd s390/idle: fix cpu idle time calculation
The idle time reported in /proc/stat sometimes incorrectly contains
huge values on s390. This is caused by a bug in arch_cpu_idle_time().

The kernel tries to figure out when a different cpu entered idle by
accessing its per-cpu data structure. There is an ordering problem: if
the remote cpu has an idle_enter value which is not zero, and an
idle_exit value which is zero, it is assumed it is idle since
"now". The "now" timestamp however is taken before the idle_enter
value is read.

Which in turn means that "now" can be smaller than idle_enter of the
remote cpu. Unconditionally subtracting idle_enter from "now" can thus
lead to a negative value (aka large unsigned value).

Fix this by moving the get_tod_clock() invocation out of the
loop. While at it also make the code a bit more readable.

A similar bug also exists for show_idle_time(). Fix this is as well.

Cc: <stable@vger.kernel.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-31 17:26:48 +01:00
Ilya Leoshkevich a1d863ac3e s390/unwind: fix mixing regs and sp
unwind_for_each_frame stops after the first frame if regs->gprs[15] <=
sp.

The reason is that in case regs are specified, the first frame should be
regs->psw.addr and the second frame should be sp->gprs[8]. However,
currently the second frame is regs->gprs[15], which confuses
outside_of_stack().

Fix by introducing a flag to distinguish this special case from
unwinding the interrupt handler, for which the current behavior is
appropriate.

Fixes: 78c98f9074 ("s390/unwind: introduce stack unwind API")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: stable@vger.kernel.org # v5.2+
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-31 17:26:48 +01:00
Ilya Leoshkevich effb83ccc8 s390: add error handling to perf_callchain_kernel
perf_callchain_kernel stops neither when it encounters a garbage
address, nor when it runs out of space. Fix both issues using x86
version as an inspiration.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-31 17:20:54 +01:00
Vasily Gorbik 6756dd9b89 s390/process: avoid custom stack unwinding in get_wchan
Currently get_wchan uses custom stack unwinding implementation which
relies on back_chain presence. Replace it with more abstract stack
unwinding api usage.

Suggested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-31 17:20:53 +01:00
Vasily Gorbik d3baaeb5ae s390: avoid double handling of "noexec" option
"noexec" option is already parsed during startup and its value is
exposed via noexec_disabled variable. Simply reuse that value during
machine facilities detection.

Suggested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-31 17:20:52 +01:00
Heiko Carstens f653e29bc2 s390/time: remove monotonic_clock()
Remove unused monotonic_clock() function.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-31 17:20:52 +01:00
Gerald Schaefer ac49303d9e s390/kaslr: add support for R_390_GLOB_DAT relocation type
Commit "bpf: Process in-kernel BTF" in linux-next introduced an undefined
__weak symbol, which results in an R_390_GLOB_DAT relocation type. That
is not yet handled by the KASLR relocation code, and the kernel stops with
the message "Unknown relocation type".

Add code to detect and handle R_390_GLOB_DAT relocation types and undefined
symbols.

Fixes: 805bc0bc23 ("s390/kernel: build a relocatable kernel")
Cc: <stable@vger.kernel.org> # v5.2+
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-22 17:55:51 +02:00
Christian Brauner fefad9ef58 seccomp: simplify secure_computing()
Afaict, the struct seccomp_data argument to secure_computing() is unused
by all current callers. So let's remove it.
The argument was added in [1]. It was added because having the arch
supply the syscall arguments used to be faster than having it done by
secure_computing() (cf. Andy's comment in [2]). This is not true anymore
though.

/* References */
[1]: 2f275de5d1 ("seccomp: Add a seccomp_data parameter secure_computing()")
[2]: https://lore.kernel.org/r/CALCETrU_fs_At-hTpr231kpaAd0z7xJN4ku-DvzhRU6cvcJA_w@mail.gmail.com

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: x86@kernel.org
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20190924064420.6353-1-christian.brauner@ubuntu.com
Signed-off-by: Kees Cook <keescook@chromium.org>
2019-10-10 14:55:24 -07:00
Frederic Weisbecker f83eeb1a01 sched/cputime: Rename vtime_account_system() to vtime_account_kernel()
vtime_account_system() decides if we need to account the time to the
system (__vtime_account_system()) or to the guest (vtime_account_guest()).

So this function is a misnomer as we are on a higher level than
"system". All we know when we call that function is that we are
accounting kernel cputime. Whether it belongs to guest or system time
is a lower level detail.

Rename this function to vtime_account_kernel(). This will clarify things
and avoid too many underscored vtime_account_system() versions.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191003161745.28464-2-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-09 12:39:25 +02:00
Thomas Richter e14e59c125 s390/cpumf: Fix indentation in sampling device driver
Fix indentation in the s390 CPU Measuement Facility
sampling device dirver.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-01 09:41:36 +02:00
Thomas Richter 932bfc5aae s390/cpumsf: Check for CPU Measurement sampling
s390 IBM z15 introduces a check if the CPU Mesurement Facility
sampling is temporarily unavailable. If this is the case return -EBUSY
and abort the setup of CPU Measuement facility sampling.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-01 09:41:36 +02:00
Thomas Richter 8513458280 s390/cpumf: Use consistant debug print format
Use consistant debug print format of the form variable
blank value.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-01 09:41:36 +02:00
Linus Torvalds aefcf2f4b5 Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull kernel lockdown mode from James Morris:
 "This is the latest iteration of the kernel lockdown patchset, from
  Matthew Garrett, David Howells and others.

  From the original description:

    This patchset introduces an optional kernel lockdown feature,
    intended to strengthen the boundary between UID 0 and the kernel.
    When enabled, various pieces of kernel functionality are restricted.
    Applications that rely on low-level access to either hardware or the
    kernel may cease working as a result - therefore this should not be
    enabled without appropriate evaluation beforehand.

    The majority of mainstream distributions have been carrying variants
    of this patchset for many years now, so there's value in providing a
    doesn't meet every distribution requirement, but gets us much closer
    to not requiring external patches.

  There are two major changes since this was last proposed for mainline:

   - Separating lockdown from EFI secure boot. Background discussion is
     covered here: https://lwn.net/Articles/751061/

   -  Implementation as an LSM, with a default stackable lockdown LSM
      module. This allows the lockdown feature to be policy-driven,
      rather than encoding an implicit policy within the mechanism.

  The new locked_down LSM hook is provided to allow LSMs to make a
  policy decision around whether kernel functionality that would allow
  tampering with or examining the runtime state of the kernel should be
  permitted.

  The included lockdown LSM provides an implementation with a simple
  policy intended for general purpose use. This policy provides a coarse
  level of granularity, controllable via the kernel command line:

    lockdown={integrity|confidentiality}

  Enable the kernel lockdown feature. If set to integrity, kernel features
  that allow userland to modify the running kernel are disabled. If set to
  confidentiality, kernel features that allow userland to extract
  confidential information from the kernel are also disabled.

  This may also be controlled via /sys/kernel/security/lockdown and
  overriden by kernel configuration.

  New or existing LSMs may implement finer-grained controls of the
  lockdown features. Refer to the lockdown_reason documentation in
  include/linux/security.h for details.

  The lockdown feature has had signficant design feedback and review
  across many subsystems. This code has been in linux-next for some
  weeks, with a few fixes applied along the way.

  Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
  when kernel lockdown is in confidentiality mode") is missing a
  Signed-off-by from its author. Matthew responded that he is providing
  this under category (c) of the DCO"

* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
  kexec: Fix file verification on S390
  security: constify some arrays in lockdown LSM
  lockdown: Print current->comm in restriction messages
  efi: Restrict efivar_ssdt_load when the kernel is locked down
  tracefs: Restrict tracefs when the kernel is locked down
  debugfs: Restrict debugfs when the kernel is locked down
  kexec: Allow kexec_file() with appropriate IMA policy when locked down
  lockdown: Lock down perf when in confidentiality mode
  bpf: Restrict bpf when kernel lockdown is in confidentiality mode
  lockdown: Lock down tracing and perf kprobes when in confidentiality mode
  lockdown: Lock down /proc/kcore
  x86/mmiotrace: Lock down the testmmiotrace module
  lockdown: Lock down module params that specify hardware parameters (eg. ioport)
  lockdown: Lock down TIOCSSERIAL
  lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
  acpi: Disable ACPI table override if the kernel is locked down
  acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
  ACPI: Limit access to custom_method when the kernel is locked down
  x86/msr: Restrict MSR access when the kernel is locked down
  x86: Lock down IO port access when the kernel is locked down
  ...
2019-09-28 08:14:15 -07:00
Linus Torvalds f1f2f614d5 Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
 "The major feature in this time is IMA support for measuring and
  appraising appended file signatures. In addition are a couple of bug
  fixes and code cleanup to use struct_size().

  In addition to the PE/COFF and IMA xattr signatures, the kexec kernel
  image may be signed with an appended signature, using the same
  scripts/sign-file tool that is used to sign kernel modules.

  Similarly, the initramfs may contain an appended signature.

  This contained a lot of refactoring of the existing appended signature
  verification code, so that IMA could retain the existing framework of
  calculating the file hash once, storing it in the IMA measurement list
  and extending the TPM, verifying the file's integrity based on a file
  hash or signature (eg. xattrs), and adding an audit record containing
  the file hash, all based on policy. (The IMA support for appended
  signatures patch set was posted and reviewed 11 times.)

  The support for appended signature paves the way for adding other
  signature verification methods, such as fs-verity, based on a single
  system-wide policy. The file hash used for verifying the signature and
  the signature, itself, can be included in the IMA measurement list"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  ima: ima_api: Use struct_size() in kzalloc()
  ima: use struct_size() in kzalloc()
  sefltest/ima: support appended signatures (modsig)
  ima: Fix use after free in ima_read_modsig()
  MODSIGN: make new include file self contained
  ima: fix freeing ongoing ahash_request
  ima: always return negative code for error
  ima: Store the measurement again when appraising a modsig
  ima: Define ima-modsig template
  ima: Collect modsig
  ima: Implement support for module-style appended signatures
  ima: Factor xattr_verify() out of ima_appraise_measurement()
  ima: Add modsig appraise_type option for module-style appended signatures
  integrity: Select CONFIG_KEYS instead of depending on it
  PKCS#7: Introduce pkcs7_get_digest()
  PKCS#7: Refactor verify_pkcs7_signature()
  MODSIGN: Export module signature definitions
  ima: initialize the "template" field with the default template
2019-09-27 19:37:27 -07:00
Vasily Gorbik f3122a79a1 s390/topology: avoid firing events before kobjs are created
arch_update_cpu_topology is first called from:
kernel_init_freeable->sched_init_smp->sched_init_domains

even before cpus has been registered in:
kernel_init_freeable->do_one_initcall->s390_smp_init

Do not trigger kobject_uevent change events until cpu devices are
actually created. Fixes the following kasan findings:

BUG: KASAN: global-out-of-bounds in kobject_uevent_env+0xb40/0xee0
Read of size 8 at addr 0000000000000020 by task swapper/0/1

BUG: KASAN: global-out-of-bounds in kobject_uevent_env+0xb36/0xee0
Read of size 8 at addr 0000000000000018 by task swapper/0/1

CPU: 0 PID: 1 Comm: swapper/0 Tainted: G    B
Hardware name: IBM 3906 M04 704 (LPAR)
Call Trace:
([<0000000143c6db7e>] show_stack+0x14e/0x1a8)
 [<0000000145956498>] dump_stack+0x1d0/0x218
 [<000000014429fb4c>] print_address_description+0x64/0x380
 [<000000014429f630>] __kasan_report+0x138/0x168
 [<0000000145960b96>] kobject_uevent_env+0xb36/0xee0
 [<0000000143c7c47c>] arch_update_cpu_topology+0x104/0x108
 [<0000000143df9e22>] sched_init_domains+0x62/0xe8
 [<000000014644c94a>] sched_init_smp+0x3a/0xc0
 [<0000000146433a20>] kernel_init_freeable+0x558/0x958
 [<000000014599002a>] kernel_init+0x22/0x160
 [<00000001459a71d4>] ret_from_fork+0x28/0x30
 [<00000001459a71dc>] kernel_thread_starter+0x0/0x10

Cc: stable@vger.kernel.org
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-09-23 23:27:52 +02:00
Thomas Richter 2cb549a821 s390/cpum_sf: Support ioctl PERF_EVENT_IOC_PERIOD
A perf_event can be set up to deliver overflow notifications
via SIGIO signal.  The setup of the event is:

 1. create event with perf_event_open()
 2. assign it a signal for I/O notification with fcntl()
 3. Install signal handler and consume samples

The initial setup of perf_event_open() determines the
period/frequency time span needed to elapse before each signal
is delivered to the user process.

While the event is active, system call
ioctl(.., PERF_EVENT_IOC_PERIOD, value) can be used the change
the frequency/period time span of the active event.
The remaining signal handler invocations honour the new value.

This does not work on s390. In fact the time span does not change
regardless of ioctl's third argument 'value'. The call succeeds
but the time span does not change.

Support this behavior and make it common with other platforms.
This is achieved by changing the interval value of the sampling
control block accordingly and feed this new value every time
the event is enabled using pmu_event_enable().

Before this change the interval value was set only once at
pmu_event_add() and never changed.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-09-19 12:56:07 +02:00
Linus Torvalds d590284419 s390 updates for the 5.4 merge window
- Add support for IBM z15 machines.
 
 - Add SHA3 and CCA AES cipher key support in zcrypt and pkey refactoring.
 
 - Move to arch_stack_walk infrastructure for the stack unwinder.
 
 - Various kasan fixes and improvements.
 
 - Various command line parsing fixes.
 
 - Improve decompressor phase debuggability.
 
 - Lift no bss usage restriction for the early code.
 
 - Use refcount_t for reference counters for couple of places in
   mm code.
 
 - Logging improvements and return code fix in vfio-ccw code.
 
 - Couple of zpci fixes and minor refactoring.
 
 - Remove some outdated documentation.
 
 - Fix secure boot detection.
 
 - Other various minor code clean ups.
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Merge tag 's390-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add support for IBM z15 machines.

 - Add SHA3 and CCA AES cipher key support in zcrypt and pkey
   refactoring.

 - Move to arch_stack_walk infrastructure for the stack unwinder.

 - Various kasan fixes and improvements.

 - Various command line parsing fixes.

 - Improve decompressor phase debuggability.

 - Lift no bss usage restriction for the early code.

 - Use refcount_t for reference counters for couple of places in mm
   code.

 - Logging improvements and return code fix in vfio-ccw code.

 - Couple of zpci fixes and minor refactoring.

 - Remove some outdated documentation.

 - Fix secure boot detection.

 - Other various minor code clean ups.

* tag 's390-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (48 commits)
  s390: remove pointless drivers-y in drivers/s390/Makefile
  s390/cpum_sf: Fix line length and format string
  s390/pci: fix MSI message data
  s390: add support for IBM z15 machines
  s390/crypto: Support for SHA3 via CPACF (MSA6)
  s390/startup: add pgm check info printing
  s390/crypto: xts-aes-s390 fix extra run-time crypto self tests finding
  vfio-ccw: fix error return code in vfio_ccw_sch_init()
  s390: vfio-ap: fix warning reset not completed
  s390/base: remove unused s390_base_mcck_handler
  s390/sclp: Fix bit checked for has_sipl
  s390/zcrypt: fix wrong handling of cca cipher keygenflags
  s390/kasan: add kdump support
  s390/setup: avoid using strncmp with hardcoded length
  s390/sclp: avoid using strncmp with hardcoded length
  s390/module: avoid using strncmp with hardcoded length
  s390/pci: avoid using strncmp with hardcoded length
  s390/kaslr: reserve memory for kasan usage
  s390/mem_detect: provide single get_mem_detect_end
  s390/cmma: reuse kstrtobool for option value parsing
  ...
2019-09-17 14:04:43 -07:00
Thomas Richter 03e9e42f79 s390/cpum_sf: Fix line length and format string
Rewrite some lines to match line length and replace
format string 0x%x to %#x.  Add and remove blank line.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-09-16 13:21:51 +02:00
Martin Schwidefsky a0e2251132 s390: add support for IBM z15 machines
Add detection for machine types 0x8562 and 8x8561 and set the ELF platform
name to z15. Add the miscellaneous-instruction-extension 3 facility to
the list of facilities for z15.

And allow to generate code that only runs on a z15 machine.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-09-13 12:19:14 +02:00
Matthew Garrett 45893a0abe kexec: Fix file verification on S390
I accidentally typoed this #ifdef, so verification would always be
disabled.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Reported-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2019-09-10 13:27:51 +01:00
Vasily Gorbik 512222789c s390/base: remove unused s390_base_mcck_handler
s390_base_mcck_handler was used during system reset if diag308 set was
not available. But after commit d485235b00 ("s390: assume diag308 set
always works") is a dead code and could be removed.

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-09-03 13:53:56 +02:00
Vasily Gorbik d0b319843b s390/setup: avoid using strncmp with hardcoded length
Replace strncmp usage in console mode setup code with simple strcmp.
Replace strncmp which is used for prefix comparison with str_has_prefix.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-29 15:34:58 +02:00
Vasily Gorbik 54fb07d030 s390/sclp: avoid using strncmp with hardcoded length
"earlyprintk" option documentation does not clearly state which
platform supports which additional values (e.g. ",keep"). Preserve old
option behaviour and reuse str_has_prefix instead of strncmp for prefix
testing.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-29 15:34:58 +02:00
Vasily Gorbik b29cd7c4c4 s390/module: avoid using strncmp with hardcoded length
Reuse str_has_prefix instead of strncmp with hardcoded length to
make the intent of a comparison more obvious.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-29 15:34:57 +02:00
Vasily Gorbik 3d64436453 s390/vdso: reuse kstrtobool for option value parsing
"vdso" option setup already recognises integer and textual values. Yet
kstrtobool is a more common way to parse boolean values, reuse it to
unify option value parsing behavior and simplify code a bit.

While at it, __setup value parsing callbacks are expected to return
1 when an option is recognized, and returning any other value won't
trigger any error message currently, so simply return 1.

Also don't change default vdso_enabled value of 1 when "vdso" option
value is invalid.

Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-26 12:51:17 +02:00
Vasily Gorbik e991e5bb11 s390/stacktrace: use common arch_stack_walk infrastructure
Use common arch_stack_walk infrastructure to avoid duplicated code and
avoid taking care of the stack storage and filtering.

Common code also uses try_get_task_stack/put_task_stack when needed which
have been missing in our code, which also solves potential problem for us.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-21 12:58:53 +02:00
Vasily Gorbik 2c7fa8a11c s390/kasan: avoid report in get_wchan
Reading other running task's stack can be a dangerous endeavor. Kasan
stack memory access instrumentation includes special prologue and epilogue
to mark/remove red zones in shadow memory between stack variables. For
that reason there is always a race between a task reading value in other
task's stack and that other task returning from a function and entering
another one generating different red zones pattern.

To avoid kasan reports simply perform uninstrumented memory reads.

Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-21 12:58:53 +02:00
Vasily Gorbik 8769f610fe s390/process: avoid potential reading of freed stack
With THREAD_INFO_IN_TASK (which is selected on s390) task's stack usage
is refcounted and should always be protected by get/put when touching
other task's stack to avoid race conditions with task's destruction code.

Fixes: d5c352cdd0 ("s390: move thread_info into task_struct")
Cc: stable@vger.kernel.org # v4.10+
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-21 12:58:52 +02:00
Vasily Gorbik 2e83e0eb85 s390: clean .bss before running uncompressed kernel
Clean uncompressed kernel .bss section in the startup code before
the uncompressed kernel is executed. At this point of time initrd and
certificates have been already rescued. Uncompressed kernel .bss size
is known from vmlinux_info. It is also taken into consideration during
uncompressed kernel positioning by kaslr (so it is safe to clean it).

With that uncompressed kernel is starting with .bss section zeroed and
no .bss section usage restrictions apply. Which makes chkbss checks for
uncompressed kernel objects obsolete and they can be removed.

early_nobss.c is also not needed anymore. Parts of it which are still
relevant are moved to early.c. Kasan initialization code is now called
directly from head64 (early.c is instrumented and should not be
executed before kasan shadow memory is set up).

Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-21 12:58:52 +02:00
Vasily Gorbik 59793c5ab9 s390: move vmalloc option parsing to startup code
Few other crucial memory setup options are already handled in
the startup code. Those values are needed by kaslr and kasan
implementations. "vmalloc" is the last piece required for future
improvements such as early decision on kernel page levels depth required
for actual memory setup, as well as vmalloc memory area access monitoring
in kasan.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-21 12:41:43 +02:00
Jiri Bohac 99d5cadfde kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE
This is a preparatory patch for kexec_file_load() lockdown.  A locked down
kernel needs to prevent unsigned kernel images from being loaded with
kexec_file_load().  Currently, the only way to force the signature
verification is compiling with KEXEC_VERIFY_SIG.  This prevents loading
usigned images even when the kernel is not locked down at runtime.

This patch splits KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE.
Analogous to the MODULE_SIG and MODULE_SIG_FORCE for modules, KEXEC_SIG
turns on the signature verification but allows unsigned images to be
loaded.  KEXEC_SIG_FORCE disallows images without a valid signature.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
cc: kexec@lists.infradead.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Heiko Carstens 404861e15b s390/vdso: map vdso also for statically linked binaries
s390 does not map the vdso for statically linked binaries, assuming
that this doesn't make sense. See commit fc5243d98a ("[S390]
arch_setup_additional_pages arguments").

However with glibc commit d665367f596d ("linux: Enable vDSO for static
linking as default (BZ#19767)") and commit 5e855c895401 ("s390: Enable
VDSO for static linking") the vdso is also used for statically linked
binaries - if the kernel would make it available.

Therefore map the vdso always, just like all other architectures.

Reported-by: Stefan Liebler <stli@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-09 11:03:28 +02:00
Vasily Gorbik 24350fdadb s390: put _stext and _etext into .text section
Perf relies on _etext and _stext symbols being one of 't', 'T', 'v' or
'V'. Put them into .text section to guarantee that.

Also moves padding to page boundary inside .text which has an effect that
.text section is now padded with nops rather than 0's, which apparently
has been the initial intention for specifying 0x0700 fill expression.

Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Suggested-by: Andreas Krebbel <krebbel@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-06 13:58:35 +02:00
Vasily Gorbik b9f23b7376 s390/head64: cleanup unused labels
Cleanup labels in head64 some of which are not being used since git
recorded history.

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-06 13:58:35 +02:00
Vasily Gorbik fd0c7435d7 s390/unwind: remove stack recursion warning
Remove pointless stack recursion on stack type ... warning, which
only confuses people. There is no way to make backchain unwinder 100%
reliable. When a task is interrupted in-between stack frame allocation
and backchain write instructions new stack frame backchain pointer is
left uninitialized (there are also sometimes additional instruction
in-between stack frame allocation and backchain write instructions due
to gcc shrink-wrapping). In attempt to unwind such stack the unwinder
would still try to use that invalid backchain value and perform all kind
of sanity checks on it to make sure we are not pointed out of stack. In
some cases that invalid backchain value would be 0 and we would falsely
treat next stackframe as pt_regs and again gprs[15] in those pt_regs
might happen to point at some address within the task's stack.

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-06 13:58:35 +02:00
Vasily Gorbik 218ddd5acf s390/setup: adjust start_code of init_mm to _text
After some investigation it doesn't look like init_mm fields
start_code/end_code are used anywhere besides potentially in dump_mm for
debugging purposes. Originally the value of 0 for start_code reflected
the presence of lowcore and early boot code. But with kaslr in place
start_code/end_code range should not span over unoccupied by the code
segment memory. So, adjust init_mm start_code to point at the beginning
of the code segment like other architectures do it.

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-06 13:58:34 +02:00
Vasily Gorbik a287a49e67 s390/protvirt: avoid memory sharing for diag 308 set/store
This reverts commit db9492cef4 ("s390/protvirt: add memory sharing for
diag 308 set/store") which due to ultravisor implementation change is
not needed after all.

Fixes: db9492cef4 ("s390/protvirt: add memory sharing for diag 308 set/store")
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-06 13:58:34 +02:00
Thiago Jung Bauermann c8424e776b MODSIGN: Export module signature definitions
IMA will use the module_signature format for append signatures, so export
the relevant definitions and factor out the code which verifies that the
appended signature trailer is valid.

Also, create a CONFIG_MODULE_SIG_FORMAT option so that IMA can select it
and be able to use mod_check_sig() without having to depend on either
CONFIG_MODULE_SIG or CONFIG_MODULES.

s390 duplicated the definition of struct module_signature so now they can
use the new <linux/module_signature.h> header instead.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Acked-by: Jessica Yu <jeyu@kernel.org>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:39:56 -04:00
Vasily Gorbik 1877011a35 s390/kexec: add missing include to machine_kexec_reloc.c
Include <asm/kexec.h> into machine_kexec_reloc.c to expose
arch_kexec_do_relocs declaration and avoid the following sparse warnings:
arch/s390/kernel/machine_kexec_reloc.c:4:5: warning: symbol 'arch_kexec_do_relocs' was not declared. Should it be static?
arch/s390/boot/../kernel/machine_kexec_reloc.c:4:5: warning: symbol 'arch_kexec_do_relocs' was not declared. Should it be static?

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-29 18:05:03 +02:00
Vasily Gorbik 06f9895fda s390/perf: make cf_diag_csd static
Since there is really no reason for cf_diag_csd per cpu variable to be
globally visible make it static to avoid the following sparse warning:
arch/s390/kernel/perf_cpum_cf_diag.c:37:1: warning: symbol 'cf_diag_csd' was not declared. Should it be static?

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-29 18:05:02 +02:00
Vasily Gorbik 5518aed82d s390: wire up clone3 system call
Tested (64-bit and compat mode) using program from
http://lkml.kernel.org/r/20190604212930.jaaztvkent32b7d3@brauner.io
with the following:
       return syscall(__NR_clone, flags, 0, pidfd, 0, 0);
changed to:
       return syscall(__NR_clone, 0, flags, pidfd, 0, 0);
due to CLONE_BACKWARDS2.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-07-23 10:45:53 +02:00
Matteo Croce eec4844fae proc/sysctl: add shared variables for range check
In the sysctl code the proc_dointvec_minmax() function is often used to
validate the user supplied value between an allowed range.  This
function uses the extra1 and extra2 members from struct ctl_table as
minimum and maximum allowed value.

On sysctl handler declaration, in every source file there are some
readonly variables containing just an integer which address is assigned
to the extra1 and extra2 members, so the sysctl range is enforced.

The special values 0, 1 and INT_MAX are very often used as range
boundary, leading duplication of variables like zero=0, one=1,
int_max=INT_MAX in different source files:

    $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l
    248

Add a const int array containing the most commonly used values, some
macros to refer more easily to the correct array member, and use them
instead of creating a local one for every object file.

This is the bloat-o-meter output comparing the old and new binary
compiled with the default Fedora config:

    # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o
    add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164)
    Data                                         old     new   delta
    sysctl_vals                                    -      12     +12
    __kstrtab_sysctl_vals                          -      12     +12
    max                                           14      10      -4
    int_max                                       16       -     -16
    one                                           68       -     -68
    zero                                         128      28    -100
    Total: Before=20583249, After=20583085, chg -0.00%

[mcroce@redhat.com: tipc: remove two unused variables]
  Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com
[akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c]
[arnd@arndb.de: proc/sysctl: make firmware loader table conditional]
  Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de
[akpm@linux-foundation.org: fix fs/eventpoll.c]
Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-18 17:08:07 -07:00
Christian Brauner 1a271a68e0
arch: mark syscall number 435 reserved for clone3
A while ago Arnd made it possible to give new system calls the same
syscall number on all architectures (except alpha). To not break this
nice new feature let's mark 435 for clone3 as reserved on all
architectures that do not yet implement it.
Even if an architecture does not plan to implement it this ensures that
new system calls coming after clone3 will have the same number on all
architectures.

Signed-off-by: Christian Brauner <christian@brauner.io>
Cc: linux-arch@vger.kernel.org
Cc: linux-alpha@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Link: https://lore.kernel.org/r/20190714192205.27190-2-christian@brauner.io
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Christian Brauner <christian@brauner.io>
2019-07-15 00:39:33 +02:00
Linus Torvalds aabfea8dc9 s390 updates for the 5.3 merge window #2
- Fix integer overflow during stack frame unwind with invalid backchain.
 
  - Cleanup unused symbol export in zcrypt code.
 
  - Fix MIO addressing control activation in PCI code and expose its
    usage via sysfs.
 
  - Fix kernel image signature verification report presence detection.
 
  - Fix irq registration in vfio-ap code.
 
  - Add CPU measurement counters for newer machines.
 
  - Add base DASD thin provisioning support and code cleanups.
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Merge tag 's390-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull more s390 updates from Vasily Gorbik:

 - Fix integer overflow during stack frame unwind with invalid
   backchain.

 - Cleanup unused symbol export in zcrypt code.

 - Fix MIO addressing control activation in PCI code and expose its
   usage via sysfs.

 - Fix kernel image signature verification report presence detection.

 - Fix irq registration in vfio-ap code.

 - Add CPU measurement counters for newer machines.

 - Add base DASD thin provisioning support and code cleanups.

* tag 's390-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (21 commits)
  s390/unwind: avoid int overflow in outside_of_stack
  s390/zcrypt: remove the exporting of ap_query_configuration
  s390/pci: add mio_enabled attribute
  s390: fix setting of mio addressing control
  s390/ipl: Fix detection of has_secure attribute
  s390: vfio-ap: fix irq registration
  s390/cpumf: Add extended counter set definitions for model 8561 and 8562
  s390/dasd: Handle out-of-space constraint
  s390/dasd: Add discard support for ESE volumes
  s390/dasd: Use ALIGN_DOWN macro
  s390/dasd: Make dasd_setup_queue() a discipline function
  s390/dasd: Add new ioctl to release space
  s390/dasd: Add dasd_sleep_on_queue_interruptible()
  s390/dasd: Add missing intensity definition
  s390/dasd: Fix whitespace
  s390/dasd: Add dynamic formatting support for ESE volumes
  s390/dasd: Recognise data for ESE volumes
  s390/dasd: Put sub-order definitions in a separate section
  s390/dasd: Make layout analysis ESE compatible
  s390/dasd: Remove old defines and function
  ...
2019-07-12 15:39:22 -07:00
Vasily Gorbik 9a15919041 s390/unwind: avoid int overflow in outside_of_stack
When current task is interrupted in-between stack frame allocation
and backchain write instructions new stack frame backchain pointer
is left uninitialized. That invalid backchain value is passed into
outside_of_stack for sanity check. Make sure int overflow does not happen
by subtracting stack_frame size from the stack "end" rather than adding
it to "random" backchain value.

Fixes: 41b0474c1b1c ("s390/unwind: introduce stack unwind API")
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-11 20:40:02 +02:00
Sebastian Ott 9964f396f1 s390: fix setting of mio addressing control
Move enablement of mio addressing control from detect_machine_facilities
to pci_base_init. detect_machine_facilities runs so early that the
static branches have not been toggled yet, thus mio addressing control
was always off. In pci_base_init we have to use the SMP aware
ctl_set_bit though.

Fixes: 833b441ec0 ("s390: enable processes for mio instructions")
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-11 20:40:02 +02:00
Philipp Rudo 1b2be2071a s390/ipl: Fix detection of has_secure attribute
Use the correct bit for detection of the machine capability associated
with the has_secure attribute. It is expected that the underlying
platform (including hypervisors) unsets the bit when they don't provide
secure ipl for their guests.

Fixes: c9896acc78 ("s390/ipl: Provide has_secure sysfs attribute")
Cc: stable@vger.kernel.org # 5.2
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-11 20:40:02 +02:00
Thomas Richter 820bace734 s390/cpumf: Add extended counter set definitions for model 8561 and 8562
Add the extended counter set definitions for s390 machine types
8561 and  8262. They are identical with machine types 3906 and
3907.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-11 20:40:01 +02:00
Linus Torvalds 5450e8a316 pidfd-updates-v5.3
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Merge tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull pidfd updates from Christian Brauner:
 "This adds two main features.

   - First, it adds polling support for pidfds. This allows process
     managers to know when a (non-parent) process dies in a race-free
     way.

     The notification mechanism used follows the same logic that is
     currently used when the parent of a task is notified of a child's
     death. With this patchset it is possible to put pidfds in an
     {e}poll loop and get reliable notifications for process (i.e.
     thread-group) exit.

   - The second feature compliments the first one by making it possible
     to retrieve pollable pidfds for processes that were not created
     using CLONE_PIDFD.

     A lot of processes get created with traditional PID-based calls
     such as fork() or clone() (without CLONE_PIDFD). For these
     processes a caller can currently not create a pollable pidfd. This
     is a problem for Android's low memory killer (LMK) and service
     managers such as systemd.

  Both patchsets are accompanied by selftests.

  It's perhaps worth noting that the work done so far and the work done
  in this branch for pidfd_open() and polling support do already see
  some adoption:

   - Android is in the process of backporting this work to all their LTS
     kernels [1]

   - Service managers make use of pidfd_send_signal but will need to
     wait until we enable waiting on pidfds for full adoption.

   - And projects I maintain make use of both pidfd_send_signal and
     CLONE_PIDFD [2] and will use polling support and pidfd_open() too"

[1] https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.9+backport%22
    https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.14+backport%22
    https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.19+backport%22

[2] aab6e3eb73/src/lxc/start.c (L1753)

* tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  tests: add pidfd_open() tests
  arch: wire-up pidfd_open()
  pid: add pidfd_open()
  pidfd: add polling selftests
  pidfd: add polling support
2019-07-10 22:17:21 -07:00
Linus Torvalds cf2d213e49 Power management updates for 5.3-rc1
- Improve the handling of shared ACPI power resources in the PCI
    bus type layer (Mika Westerberg).
 
  - Make the PCI layer take link delays required by the PCIe spec
    into account as appropriate and avoid polling devices in D3cold
    for PME (Mika Westerberg).
 
  - Fix some corner case issues in ACPI device power management and
    in the PCI bus type layer, optimiza and clean up the handling of
    runtime-suspended PCI devices during system-wide transitions to
    sleep states (Rafael Wysocki).
 
  - Rework hibernation handling in the ACPI core and the PCI bus type
    to resume runtime-suspended devices before hibernation (which
    allows some functional problems to be avoided) and fix some ACPI
    power management issues related to hiberation (Rafael Wysocki).
 
  - Extend the operating performance points (OPP) framework to support
    a wider range of devices (Rajendra Nayak, Stehpen Boyd).
 
  - Fix issues related to genpd_virt_devs and issues with platforms
    using the set_opp() callback in the OPP framework (Viresh Kumar,
    Dmitry Osipenko).
 
  - Add new cpufreq driver for Raspberry Pi (Nicolas Saenz Julienne).
 
  - Add new cpufreq driver for imx8m and imx7d chips (Leonard Crestez).
 
  - Fix and clean up the pcc-cpufreq, brcmstb-avs-cpufreq, s5pv210,
    and armada-37xx cpufreq drivers (David Arcari, Florian Fainelli,
    Paweł Chmiel, YueHaibing).
 
  - Clean up and fix the cpufreq core (Viresh Kumar, Daniel Lezcano).
 
  - Fix minor issue in the ACPI system sleep support code and export
    one function from it (Lenny Szubowicz, Dexuan Cui).
 
  - Clean up assorted pieces of PM code and documentation (Kefeng Wang,
    Andy Shevchenko, Bart Van Assche, Greg Kroah-Hartman, Fuqian Huang,
    Geert Uytterhoeven, Mathieu Malaterre, Rafael Wysocki).
 
  - Update the pm-graph utility to v5.4 (Todd Brandt).
 
  - Fix and clean up the cpupower utility (Abhishek Goel, Nick Black).
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Merge tag 'pm-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These update PCI and ACPI power management (improved handling of ACPI
  power resources and PCIe link delays, fixes related to corner cases,
  hibernation handling rework), fix and extend the operating performance
  points (OPP) framework, add new cpufreq drivers for Raspberry Pi and
  imx8m chips, update some other cpufreq drivers, clean up assorted
  pieces of PM code and documentation and update tools.

  Specifics:

   - Improve the handling of shared ACPI power resources in the PCI bus
     type layer (Mika Westerberg).

   - Make the PCI layer take link delays required by the PCIe spec into
     account as appropriate and avoid polling devices in D3cold for PME
     (Mika Westerberg).

   - Fix some corner case issues in ACPI device power management and in
     the PCI bus type layer, optimiza and clean up the handling of
     runtime-suspended PCI devices during system-wide transitions to
     sleep states (Rafael Wysocki).

   - Rework hibernation handling in the ACPI core and the PCI bus type
     to resume runtime-suspended devices before hibernation (which
     allows some functional problems to be avoided) and fix some ACPI
     power management issues related to hiberation (Rafael Wysocki).

   - Extend the operating performance points (OPP) framework to support
     a wider range of devices (Rajendra Nayak, Stehpen Boyd).

   - Fix issues related to genpd_virt_devs and issues with platforms
     using the set_opp() callback in the OPP framework (Viresh Kumar,
     Dmitry Osipenko).

   - Add new cpufreq driver for Raspberry Pi (Nicolas Saenz Julienne).

   - Add new cpufreq driver for imx8m and imx7d chips (Leonard Crestez).

   - Fix and clean up the pcc-cpufreq, brcmstb-avs-cpufreq, s5pv210, and
     armada-37xx cpufreq drivers (David Arcari, Florian Fainelli, Paweł
     Chmiel, YueHaibing).

   - Clean up and fix the cpufreq core (Viresh Kumar, Daniel Lezcano).

   - Fix minor issue in the ACPI system sleep support code and export
     one function from it (Lenny Szubowicz, Dexuan Cui).

   - Clean up assorted pieces of PM code and documentation (Kefeng Wang,
     Andy Shevchenko, Bart Van Assche, Greg Kroah-Hartman, Fuqian Huang,
     Geert Uytterhoeven, Mathieu Malaterre, Rafael Wysocki).

   - Update the pm-graph utility to v5.4 (Todd Brandt).

   - Fix and clean up the cpupower utility (Abhishek Goel, Nick Black)"

* tag 'pm-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (57 commits)
  ACPI: PM: Make acpi_sleep_state_supported() non-static
  PM: sleep: Drop dev_pm_skip_next_resume_phases()
  ACPI: PM: Unexport acpi_device_get_power()
  Documentation: ABI: power: Add missing newline at end of file
  ACPI: PM: Drop unused function and function header
  ACPI: PM: Introduce "poweroff" callbacks for ACPI PM domain and LPSS
  ACPI: PM: Simplify and fix PM domain hibernation callbacks
  PCI: PM: Simplify bus-level hibernation callbacks
  PM: ACPI/PCI: Resume all devices during hibernation
  cpufreq: Avoid calling cpufreq_verify_current_freq() from handle_update()
  cpufreq: Consolidate cpufreq_update_current_freq() and __cpufreq_get()
  kernel: power: swap: use kzalloc() instead of kmalloc() followed by memset()
  cpufreq: Don't skip frequency validation for has_target() drivers
  PCI: PM/ACPI: Refresh all stale power state data in pci_pm_complete()
  PCI / ACPI: Add _PR0 dependent devices
  ACPI / PM: Introduce concept of a _PR0 dependent device
  PCI / ACPI: Use cached ACPI device state to get PCI device power state
  ACPI: PM: Allow transitions to D0 to occur in special cases
  ACPI: PM: Avoid evaluating _PS3 on transitions from D3hot to D3cold
  cpufreq: Use has_target() instead of !setpolicy
  ...
2019-07-09 10:05:22 -07:00
Linus Torvalds 5ad18b2e60 Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull force_sig() argument change from Eric Biederman:
 "A source of error over the years has been that force_sig has taken a
  task parameter when it is only safe to use force_sig with the current
  task.

  The force_sig function is built for delivering synchronous signals
  such as SIGSEGV where the userspace application caused a synchronous
  fault (such as a page fault) and the kernel responded with a signal.

  Because the name force_sig does not make this clear, and because the
  force_sig takes a task parameter the function force_sig has been
  abused for sending other kinds of signals over the years. Slowly those
  have been fixed when the oopses have been tracked down.

  This set of changes fixes the remaining abusers of force_sig and
  carefully rips out the task parameter from force_sig and friends
  making this kind of error almost impossible in the future"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
  signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
  signal: Remove the signal number and task parameters from force_sig_info
  signal: Factor force_sig_info_to_task out of force_sig_info
  signal: Generate the siginfo in force_sig
  signal: Move the computation of force into send_signal and correct it.
  signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
  signal: Remove the task parameter from force_sig_fault
  signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
  signal: Explicitly call force_sig_fault on current
  signal/unicore32: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from ptrace_break
  signal/nds32: Remove tsk parameter from send_sigtrap
  signal/riscv: Remove tsk parameter from do_trap
  signal/sh: Remove tsk parameter from force_sig_info_fault
  signal/um: Remove task parameter from send_sigtrap
  signal/x86: Remove task parameter from send_sigtrap
  signal: Remove task parameter from force_sig_mceerr
  signal: Remove task parameter from force_sig
  signal: Remove task parameter from force_sigsegv
  ...
2019-07-08 21:48:15 -07:00
Steffen Maier 0328e519a7 docs: s390: unify and update s390dbf kdocs at debug.c
For non-static-inlines, debug.c already had non-compliant function
header docs. So move the pure prototype kdocs of
("s390: include/asm/debug.h add kerneldoc markups")
from debug.h to debug.c and merge them with the old function docs.
Also, I had the impression that kdoc typically is at the implementation
in the compile unit rather than at the prototype in the header file.

While at it, update the short kdoc description to distinguish the
different functions. And a few more consistency cleanups.

Added a new kdoc for debug_set_critical() since debug.h comments it
as part of the API.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <1562149189-1417-3-git-send-email-maier@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-05 13:42:22 +02:00
Vasily Gorbik 2095574632 s390/kasan: avoid false positives during stack unwind
Avoid kasan false positive when current task is interrupted in-between
stack frame allocation and backchain write instructions leaving new stack
frame backchain invalid. In particular if backchain is 0 the unwinder
tries to read pt_regs from the stack and might hit kasan poisoned bytes,
leading to kasan "stack-out-of-bounds" report.

Disable kasan instrumentation of unwinder stack reads, since this
limitation couldn't be handled otherwise with current backchain unwinder
implementation.

Fixes: 78c98f9074 ("s390/unwind: introduce stack unwind API")
Reported-by: Julian Wiedmann <jwi@linux.ibm.com>
Tested-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-02 16:00:27 +02:00
Christian Brauner 7615d9e178
arch: wire-up pidfd_open()
This wires up the pidfd_open() syscall into all arches at once.

Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jann Horn <jannh@google.com>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-api@vger.kernel.org
Cc: linux-alpha@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: linux-arch@vger.kernel.org
Cc: x86@kernel.org
2019-06-28 12:17:55 +02:00
Heiko Carstens 4ecf0a43e7 processor: get rid of cpu_relax_yield
stop_machine is the only user left of cpu_relax_yield. Given that it
now has special semantics which are tied to stop_machine introduce a
weak stop_machine_yield function which architectures can override, and
get rid of the generic cpu_relax_yield implementation.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:55 +02:00
Martin Schwidefsky 38f2c691a4 s390: improve wait logic of stop_machine
The stop_machine loop to advance the state machine and to wait for all
affected CPUs to check-in calls cpu_relax_yield in a tight loop until
the last missing CPUs acknowledged the state transition.

On a virtual system where not all logical CPUs are backed by real CPUs
all the time it can take a while for all CPUs to check-in. With the
current definition of cpu_relax_yield a diagnose 0x44 is done which
tells the hypervisor to schedule *some* other CPU. That can be any
CPU and not necessarily one of the CPUs that need to run in order to
advance the state machine. This can lead to a pretty bad diagnose 0x44
storm until the last missing CPU finally checked-in.

Replace the undirected cpu_relax_yield based on diagnose 0x44 with a
directed yield. Each CPU in the wait loop will pick up the next CPU
in the cpumask of stop_machine. The diagnose 0x9c is used to tell the
hypervisor to run this next CPU instead of the current one. If there
is only a limited number of real CPUs backing the virtual CPUs we
end up with the real CPUs passed around in a round-robin fashion.

[heiko.carstens@de.ibm.com]:
    Use cpumask_next_wrap as suggested by Peter Zijlstra.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:52 +02:00
Vasily Gorbik b4e3133b65 s390/traps: simplify data exception handler
Simplify conditions and remove unnecessary variable in data exception
handler.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:45 +02:00
Mathieu Malaterre 1ec0cd8286 PM: hibernate: powerpc: Expose pfn_is_nosave() prototype
The declaration for pfn_is_nosave is only available in
kernel/power/power.h. Since this function can be override in arch,
expose it globally. Having a prototype will make sure to avoid warning
(sometime treated as error with W=1) such as:

  arch/powerpc/kernel/suspend.c:18:5: error: no previous prototype for 'pfn_is_nosave' [-Werror=missing-prototypes]

This moves the declaration into a globally visible header file and add
missing include to avoid a warning on powerpc.

Also remove the duplicated prototypes since not required anymore.

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-06-14 10:48:56 +02:00
Heiko Carstens 2980ba6ae8 s390/kdump: get rid of compile warning
Move the CONFIG_CRASH_DUMP ifdef to get rid of this:

arch/s390/kernel/machine_kexec.c:146:22: warning: 'do_start_kdump' defined but not used [-Wunused-function]

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-11 09:48:39 +02:00