was introduced by a patch that tried to fix one bug, but by doing so created
another bug. As both bugs corrupt the output (but they do not crash the
kernel), I decided to fix the design such that it could have both bugs
fixed. The original fix, fixed time reporting of the function graph tracer
when doing a max_depth of one. This was code that can test how much the
kernel interferes with userspace. But in doing so, it could corrupt the time
keeping of the function profiler.
The issue is that the curr_ret_stack variable was being used for two
different meanings. One was to keep track of the stack pointer on the
ret_stack (shadow stack used by the function graph tracer), and the other
use case was the graph call depth. Although, the two may be closely
related, where they got updated was the issue that lead to the two different
bugs that required the two use cases to be updated differently.
The big issue with this fix is that it requires changing each architecture.
The good news is, I was able to remove a lot of code that was duplicated
within the architectures and place it into a single location. Then I could
make the fix in one place.
I pushed this code into linux-next to let it settle over a week, and before
doing so, I cross compiled all the affected architectures to make sure that
they built fine.
In the mean time, I also pulled in a patch that fixes the sched_switch
previous tasks state output, that was not actually correct.
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Merge tag 'trace-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"While rewriting the function graph tracer, I discovered a design flaw
that was introduced by a patch that tried to fix one bug, but by doing
so created another bug.
As both bugs corrupt the output (but they do not crash the kernel), I
decided to fix the design such that it could have both bugs fixed. The
original fix, fixed time reporting of the function graph tracer when
doing a max_depth of one. This was code that can test how much the
kernel interferes with userspace. But in doing so, it could corrupt
the time keeping of the function profiler.
The issue is that the curr_ret_stack variable was being used for two
different meanings. One was to keep track of the stack pointer on the
ret_stack (shadow stack used by the function graph tracer), and the
other use case was the graph call depth. Although, the two may be
closely related, where they got updated was the issue that lead to the
two different bugs that required the two use cases to be updated
differently.
The big issue with this fix is that it requires changing each
architecture. The good news is, I was able to remove a lot of code
that was duplicated within the architectures and place it into a
single location. Then I could make the fix in one place.
I pushed this code into linux-next to let it settle over a week, and
before doing so, I cross compiled all the affected architectures to
make sure that they built fine.
In the mean time, I also pulled in a patch that fixes the sched_switch
previous tasks state output, that was not actually correct"
* tag 'trace-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
sched, trace: Fix prev_state output in sched_switch tracepoint
function_graph: Have profiler use curr_ret_stack and not depth
function_graph: Reverse the order of pushing the ret_stack and the callback
function_graph: Move return callback before update of curr_ret_stack
function_graph: Use new curr_ret_depth to manage depth instead of curr_ret_stack
function_graph: Make ftrace_push_return_trace() static
sparc/function_graph: Simplify with function_graph_enter()
sh/function_graph: Simplify with function_graph_enter()
s390/function_graph: Simplify with function_graph_enter()
riscv/function_graph: Simplify with function_graph_enter()
powerpc/function_graph: Simplify with function_graph_enter()
parisc: function_graph: Simplify with function_graph_enter()
nds32: function_graph: Simplify with function_graph_enter()
MIPS: function_graph: Simplify with function_graph_enter()
microblaze: function_graph: Simplify with function_graph_enter()
arm64: function_graph: Simplify with function_graph_enter()
ARM: function_graph: Simplify with function_graph_enter()
x86/function_graph: Simplify with function_graph_enter()
function_graph: Create function_graph_enter() to consolidate architecture code
The function_graph_enter() function does the work of calling the function
graph hook function and the management of the shadow stack, simplifying the
work done in the architecture dependent prepare_ftrace_return().
Have s390 use the new code, and remove the shadow stack management as well as
having to set up the trace structure.
This is needed to prepare for a fix of a design bug on how the curr_ret_stack
is used.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Julian Wiedmann <jwi@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
On s390 command perf top fails
[root@s35lp76 perf] # ./perf top -F100000 --stdio
Error:
cycles: PMU Hardware doesn't support sampling/overflow-interrupts.
Try 'perf stat'
[root@s35lp76 perf] #
Using event -e rb0000 works as designed. Event rb0000 is the event
number of the sampling facility for basic sampling.
During system start up the following PMUs are installed in the kernel's
PMU list (from head to tail):
cpum_cf --> s390 PMU counter facility device driver
cpum_sf --> s390 PMU sampling facility device driver
uprobe
kprobe
tracepoint
task_clock
cpu_clock
Perf top executes following functions and calls perf_event_open(2) system
call with different parameters many times:
cmd_top
--> __cmd_top
--> perf_evlist__add_default
--> __perf_evlist__add_default
--> perf_evlist__new_cycles (creates event type:0 (HW)
config 0 (CPU_CYCLES)
--> perf_event_attr__set_max_precise_ip
Uses perf_event_open(2) to detect correct
precise_ip level. Fails 3 times on s390 which is ok.
Then functions cmd_top
--> __cmd_top
--> perf_top__start_counters
-->perf_evlist__config
--> perf_can_comm_exec
--> perf_probe_api
This functions test support for the following events:
"cycles:u", "instructions:u", "cpu-clock:u" using
--> perf_do_probe_api
--> perf_event_open_cloexec
Test the close on exec flag support with
perf_event_open(2).
perf_do_probe_api returns true if the event is
supported.
The function returns true because event cpu-clock is
supported by the PMU cpu_clock.
This is achieved by many calls to perf_event_open(2).
Function perf_top__start_counters now calls perf_evsel__open() for every
event, which is the default event cpu_cycles (config:0) and type HARDWARE
(type:0) which a predfined frequence of 4000.
Given the above order of the PMU list, the PMU cpum_cf gets called first
and returns 0, which indicates support for this sampling. The event is
fully allocated in the function perf_event_open (file kernel/event/core.c
near line 10521 and the following check fails:
event = perf_event_alloc(&attr, cpu, task, group_leader, NULL,
NULL, NULL, cgroup_fd);
if (IS_ERR(event)) {
err = PTR_ERR(event);
goto err_cred;
}
if (is_sampling_event(event)) {
if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) {
err = -EOPNOTSUPP;
goto err_alloc;
}
}
The check for the interrupt capabilities fails and the system call
perf_event_open() returns -EOPNOTSUPP (-95).
Add a check to return -ENODEV when sampling is requested in PMU cpum_cf.
This allows common kernel code in the perf_event_open() system call to
test the next PMU in above list.
Fixes: 97b1198fec (" "s390, perf: Use common PMU interrupt disabled code")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- A fix for the pgtable_bytes misaccounting on s390. The patch changes
common code part in regard to page table folding and adds extra
checks to mm_[inc|dec]_nr_[pmds|puds].
- Add FORCE for all build targets using if_changed
- Use non-loadable phdr for the .vmlinux.info section to avoid
a segment overlap that confuses kexec
- Cleanup the attribute definition for the diagnostic sampling
- Increase stack size for CONFIG_KASAN=y builds
- Export __node_distance to fix a build error
- Correct return code of a PMU event init function
- An update for the default configs
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Merge tag 's390-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Martin Schwidefsky:
- A fix for the pgtable_bytes misaccounting on s390. The patch changes
common code part in regard to page table folding and adds extra
checks to mm_[inc|dec]_nr_[pmds|puds].
- Add FORCE for all build targets using if_changed
- Use non-loadable phdr for the .vmlinux.info section to avoid a
segment overlap that confuses kexec
- Cleanup the attribute definition for the diagnostic sampling
- Increase stack size for CONFIG_KASAN=y builds
- Export __node_distance to fix a build error
- Correct return code of a PMU event init function
- An update for the default configs
* tag 's390-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/perf: Change CPUM_CF return code in event init function
s390: update defconfigs
s390/mm: Fix ERROR: "__node_distance" undefined!
s390/kasan: increase instrumented stack size to 64k
s390/cpum_sf: Rework attribute definition for diagnostic sampling
s390/mm: fix mis-accounting of pgtable_bytes
mm: add mm_pxd_folded checks to pgtable_bytes accounting functions
mm: introduce mm_[p4d|pud|pmd]_folded
mm: make the __PAGETABLE_PxD_FOLDED defines non-empty
s390: avoid vmlinux segments overlap
s390/vdso: add missing FORCE to build targets
s390/decompressor: add missing FORCE to build targets
The function perf_init_event() creates a new event and
assignes it to a PMU. This a done in a loop over all existing
PMUs. For each listed PMU the event init function is called
and if this function does return any other error than -ENOENT,
the loop is terminated the creation of the event fails.
If the event is invalid, return -ENOENT to try other PMUs.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Previously, the attribute entry for diagnostic sampling was added
if authorized. Otherwise, the array of struct attribute contains
two NULL values.
Change this logic and reserve space for the attribute for diagnostic
sampling. If diagnostic sampling is authorized, add an entry in the
respective position in the array of struct attribute.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move remaining definitions and declarations from include/linux/bootmem.h
into include/linux/memblock.h and remove the redundant header.
The includes were replaced with the semantic patch below and then
semi-automated removal of duplicated '#include <linux/memblock.h>
@@
@@
- #include <linux/bootmem.h>
+ #include <linux/memblock.h>
[sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h]
Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au
[sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h]
Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au
[sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal]
Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au
Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Michal Hocko <mhocko@suse.com>
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 Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make it explicit that the caller gets a physical address rather than a
virtual one.
This will also allow using meblock_alloc prefix for memblock allocations
returning virtual address, which is done in the following patches.
The conversion is done using the following semantic patch:
@@
expression e1, e2, e3;
@@
(
- memblock_alloc(e1, e2)
+ memblock_phys_alloc(e1, e2)
|
- memblock_alloc_nid(e1, e2, e3)
+ memblock_phys_alloc_nid(e1, e2, e3)
|
- memblock_alloc_try_nid(e1, e2, e3)
+ memblock_phys_alloc_try_nid(e1, e2, e3)
)
Link: http://lkml.kernel.org/r/1536927045-23536-7-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
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 Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently .vmlinux.info section of uncompressed vmlinux elf image is
included into the data segment and load address specified as 0. That
extends data segment to address 0 and makes "text" and "data" segments
overlap.
Program Headers:
Type Offset VirtAddr PhysAddr
FileSiz MemSiz Flags Align
LOAD 0x0000000000001000 0x0000000000100000 0x0000000000100000
0x0000000000ead03c 0x0000000000ead03c R E 0x1000
LOAD 0x0000000000eaf000 0x0000000000000000 0x0000000000000000
0x0000000001a13400 0x000000000233b520 RWE 0x1000
NOTE 0x0000000000eae000 0x0000000000fad000 0x0000000000fad000
0x000000000000003c 0x000000000000003c 0x4
Section to Segment mapping:
Segment Sections...
00 .text .notes
01 .rodata __ksymtab __ksymtab_gpl __ksymtab_strings __param
__modver .data..ro_after_init __ex_table .data __bug_table .init.text
.exit.text .exit.data .altinstructions .altinstr_replacement
.nospec_call_table .nospec_return_table .boot.data .init.data
.data..percpu .bss .vmlinux.info
02 .notes
Later when vmlinux.bin is produced from vmlinux, .vmlinux.info section
is removed. But elf vmlinux file, even though it is not bootable anymore,
used for debugging and loadable segments overlap should be avoided.
Utilize special ":NONE" phdr specification to avoid adding .vmlinux.info
into loadable data segment. Also set .vmlinux.info section type to INFO,
which allows to get a not-loadable info CONTENTS section.
Since minimal supported version of binutils 2.20 does not have
--dump-section objcopy option, make .vmlinux.info section loadable during
info.bin creation to get actual section contents.
Reported-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
According to Documentation/kbuild/makefiles.txt all build targets using
if_changed should use FORCE as well. Add missing FORCE to make sure
vdso targets are rebuild properly when not just immediate prerequisites
have changed but also when build command differs.
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull locking and misc x86 updates from Ingo Molnar:
"Lots of changes in this cycle - in part because locking/core attracted
a number of related x86 low level work which was easier to handle in a
single tree:
- Linux Kernel Memory Consistency Model updates (Alan Stern, Paul E.
McKenney, Andrea Parri)
- lockdep scalability improvements and micro-optimizations (Waiman
Long)
- rwsem improvements (Waiman Long)
- spinlock micro-optimization (Matthew Wilcox)
- qspinlocks: Provide a liveness guarantee (more fairness) on x86.
(Peter Zijlstra)
- Add support for relative references in jump tables on arm64, x86
and s390 to optimize jump labels (Ard Biesheuvel, Heiko Carstens)
- Be a lot less permissive on weird (kernel address) uaccess faults
on x86: BUG() when uaccess helpers fault on kernel addresses (Jann
Horn)
- macrofy x86 asm statements to un-confuse the GCC inliner. (Nadav
Amit)
- ... and a handful of other smaller changes as well"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
locking/lockdep: Make global debug_locks* variables read-mostly
locking/lockdep: Fix debug_locks off performance problem
locking/pvqspinlock: Extend node size when pvqspinlock is configured
locking/qspinlock_stat: Count instances of nested lock slowpaths
locking/qspinlock, x86: Provide liveness guarantee
x86/asm: 'Simplify' GEN_*_RMWcc() macros
locking/qspinlock: Rework some comments
locking/qspinlock: Re-order code
locking/lockdep: Remove duplicated 'lock_class_ops' percpu array
x86/defconfig: Enable CONFIG_USB_XHCI_HCD=y
futex: Replace spin_is_locked() with lockdep
locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y
x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs
x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs
x86/extable: Macrofy inline assembly code to work around GCC inlining bugs
x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops
x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs
x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs
x86/refcount: Work around GCC inlining bug
x86/objtool: Use asm macros to work around GCC inlining bugs
...
Return an error when the function debug_register() fails allocating
the debug handle.
Also remove the registered debug handle when the initialization fails
later on.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When running as a level 3 guest with no host provided sthyi support
sclp_ocf_cpc_name_copy() will only return zeroes. Zeroes are not a
valid group name, so let's not indicate that the group name field is
valid.
Also the group name is not dependent on stsi, let's not return based
on stsi before setting it.
Fixes: 95ca2cb579 ("KVM: s390: Add sthyi emulation")
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With the introduction of the module area on top of the vmalloc area, the
calculation of VMALLOC_START in setup_memory_end() function hasn't been
adjusted. As a result we got vmalloc area 2 Gb (MODULES_LEN) smaller than
it should be and the preceding vmemmap area got extra memory instead.
The patch fixes this calculation error although there were no visible
negative effects.
Apart from that, change 'tmp' variable to 'vmemmap' in memory_end
calculation for better readability.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With pointer obfuscation the output of show_registers() became quite useless:
Krnl PSW : (____ptrval____) (____ptrval____) (__list_add_valid+0x98/0xa8)
In order to print the psw mask and address use %px instead of %p.
And the output looks again like this:
Krnl PSW : 0404d00180000000 00000000007c0dd0 (__list_add_valid+0x98/0xa8)
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
By default 3-level paging is used when the kernel is compiled with
kasan support. Add 4-level paging option to support systems with more
then 3TB of physical memory and to cover 4-level paging specific code
with kasan as well.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Some functions from both arch/s390/kernel/ipl.c and
arch/s390/kernel/machine_kexec.c are called without DAT enabled
(or with and without DAT enabled code paths). There is no easy way
to partially disable kasan for those files without a substantial
rework. Disable kasan for both files for now.
To avoid disabling kasan for arch/s390/kernel/diag.c DAT flag is
enabled in diag308 call. pcpu_delegate which disables DAT is marked
with __no_sanitize_address to disable instrumentation for that one
function.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
smp_start_secondary function is called without DAT enabled. To avoid
disabling kasan instrumentation for entire arch/s390/kernel/smp.c
smp_start_secondary has been split in 2 parts. smp_start_secondary has
instrumentation disabled, it does minimal setup and enables DAT. Then
instrumentated __smp_start_secondary is called to do the rest.
__load_psw_mask function instrumentation has been disabled as well
to be able to call it from smp_start_secondary.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
To lower memory footprint and speed up kasan initialisation detect
EDAT availability and use large pages if possible. As we know how
much memory is needed for initialisation, another simplistic large
page allocator is introduced to avoid memory fragmentation.
Since facilities list is retrieved anyhow, detect noexec support and
adjust pages attributes. Handle noexec kernel option to avoid inconsistent
kasan shadow memory pages flags.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move from modules area entire shadow memory preallocation to dynamic
allocation per module load.
This behaivior has been introduced for x86 with bebf56a1b: "This patch
also forces module_alloc() to return 8*PAGE_SIZE aligned address making
shadow memory handling ( kasan_module_alloc()/kasan_module_free() )
more simple. Such alignment guarantees that each shadow page backing
modules address space correspond to only one module_alloc() allocation"
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Kasan needs 1/8 of kernel virtual address space to be reserved as the
shadow area. And eventually it requires the shadow memory offset to be
known at compile time (passed to the compiler when full instrumentation
is enabled). Any value picked as the shadow area offset for 3-level
paging would eat up identity mapping on 4-level paging (with 1PB
shadow area size). So, the kernel sticks to 3-level paging when kasan
is enabled. 3TB border is picked as the shadow offset. The memory
layout is adjusted so, that physical memory border does not exceed
KASAN_SHADOW_START and vmemmap does not go below KASAN_SHADOW_END.
Due to the fact that on s390 paging is set up very late and to cover
more code with kasan instrumentation, temporary identity mapping and
final shadow memory are set up early. The shadow memory mapping is
later carried over to init_mm.pgd during paging_init.
For the needs of paging structures allocation and shadow memory
population a primitive allocator is used, which simply chops off
memory blocks from the end of the physical memory.
Kasan currenty doesn't track vmemmap and vmalloc areas.
Current memory layout (for 3-level paging, 2GB physical memory).
---[ Identity Mapping ]---
0x0000000000000000-0x0000000000100000
---[ Kernel Image Start ]---
0x0000000000100000-0x0000000002b00000
---[ Kernel Image End ]---
0x0000000002b00000-0x0000000080000000 2G <- physical memory border
0x0000000080000000-0x0000030000000000 3070G PUD I
---[ Kasan Shadow Start ]---
0x0000030000000000-0x0000030010000000 256M PMD RW X <- shadow for 2G memory
0x0000030010000000-0x0000037ff0000000 523776M PTE RO NX <- kasan zero ro page
0x0000037ff0000000-0x0000038000000000 256M PMD RW X <- shadow for 2G modules
---[ Kasan Shadow End ]---
0x0000038000000000-0x000003d100000000 324G PUD I
---[ vmemmap Area ]---
0x000003d100000000-0x000003e080000000
---[ vmalloc Area ]---
0x000003e080000000-0x000003ff80000000
---[ Modules Area ]---
0x000003ff80000000-0x0000040000000000 2G
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Instrumented C code cannot run without the kasan shadow area. Exempt
source code files from kasan which are running before / used during
kasan initialization.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
vdso is mapped into user space processes, which won't have kasan
shodow mapped.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
To distinguish zfcpdump case and to be able to parse some of the kernel
command line arguments early (e.g. mem=) ipl block retrieval and command
line construction code is moved to the early boot phase.
"memory_end" is set up correctly respecting "mem=" and hsa_size in case
of the zfcpdump.
arch/s390/boot/string.c is introduced to provide string handling and
command line parsing functions to early boot phase code for the compressed
kernel image case.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Print mem_detect info source when memblock=debug is specified.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move memory detection to early boot phase. To store online memory
regions "struct mem_detect_info" has been introduced together with
for_each_mem_detect_block iterator. mem_detect_info is later converted
to memblock.
Also introduces sclp_early_get_meminfo function to get maximum physical
memory and maximum increment number.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce .boot.data section which is "shared" between the decompressor
code and the decompressed kernel. The decompressor will store values in
it, and copy over to the decompressed image before starting it. This
method allows to avoid using pre-defined addresses and other hacks to
pass values between those boot phases.
.boot.data section is a part of init data, and will be freed after kernel
initialization is complete.
For uncompressed kernel image, .boot.data section is basically the same
as .init.data
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
To avoid multi-stage initrd rescue operation and to simplify
assumptions during early memory allocations move initrd at some final
safe destination as early as possible. This would also allow us to
drop .bss usage restrictions for some files.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The kernel decompressor has to know several bits of information about
uncompressed image. Currently this info is collected by running "nm" on
uncompressed vmlinux + "sed" and producing sizes.h file. This method
worked well, but it has several disadvantages. Obscure symbols name
pattern matching is fragile. Adding new values makes pattern even
longer. Logic is spread across code and make file. Limited ability to
adjust symbols values (currently magic lma value of 0x100000 is always
subtracted). Apart from that same pieces of information (and more)
would be needed for early memory detection and features like KASLR
outside of boot/compressed/ folder where sizes.h is generated.
To overcome limitations new "struct vmlinux_info" has been introduced
to include values needed for the decompressor and the rest of the
boot code. The only static instance of vmlinux_info is produced during
vmlinux link step by filling in struct fields by the linker (like it is
done with input_data in boot/compressed/vmlinux.scr.lds.S). This way
individual values could be adjusted with all the knowledge linker has
and arithmetic it supports. Later .vmlinux.info section (which contains
struct vmlinux_info) is transplanted into the decompressor image and
dropped from uncompressed image altogether.
While doing that replace "compressed/vmlinux.scr.lds.S" linker
script (whose purpose is to rename .data section in piggy.o to
.rodata.compressed) with plain objcopy command. And simplify
decompressor's linker script.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove STACK_ORDER and STACK_SIZE in favour of identical THREAD_SIZE_ORDER
and THREAD_SIZE definitions. THREAD_SIZE and THREAD_SIZE_ORDER naming is
misleading since it is used as general kernel stack size information. But
both those definitions are used in the common code and throughout
architectures specific code, so changing the naming is problematic.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With virtually mapped kernel stacks the kernel stack overflow detection
is now fault based, every stack has a guard page in the vmalloc space.
The panic_stack is renamed to nodat_stack and is used for all function
that need to run without DAT, e.g. memcpy_real or do_start_kdump.
The main effect is a reduction in the kernel image size as with vmap
stacks the old style overflow checking that adds two instructions per
function is not needed anymore. Result from bloat-o-meter:
add/remove: 20/1 grow/shrink: 13/26854 up/down: 2198/-216240 (-214042)
In regard to performance the micro-benchmark for fork has a hit of a
few microseconds, allocating 4 pages in vmalloc space is more expensive
compare to an order-2 page allocation. But with real workload I could
not find a noticeable difference.
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit e872267b8b ("jump_table: move entries into ro_after_init
region") moved the __jump_table input section into the __ro_after_init
output section, but inadvertently put the macro in the wrong place in
the s390 linker script. Let's fix that.
Fixes: e872267b8b ("jump_table: move entries into ro_after_init region")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: linux-s390@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20180930164950.3841-1-ard.biesheuvel@linaro.org
The __jump_table sections emitted into the core kernel and into
each module consist of statically initialized references into
other parts of the code, and with the exception of entries that
point into init code, which are defused at post-init time, these
data structures are never modified.
So let's move them into the ro_after_init section, to prevent them
from being corrupted inadvertently by buggy code, or deliberately
by an attacker.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: https://lkml.kernel.org/r/20180919065144.25010-9-ard.biesheuvel@linaro.org
Correct stack frame overhead for 31-bit vdso, which should be 96 rather
then 160. This is done by reusing STACK_FRAME_OVERHEAD definition which
contains correct value based on build flags. This fixes stack unwinding
within vdso code for 31-bit processes. While at it replace all hard coded
stack frame overhead values with the same definition in vdso64 as well.
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
vdso_fault used is_compat_task function (on s390 it tests "current"
thread_info flags) to distinguish compat tasks and map 31-bit vdso
pages. But "current" task might not correspond to mm context.
When 31-bit compat inferior is executed under gdb, gdb does
PTRACE_PEEKTEXT on vdso page, causing vdso_fault with "current" being
64-bit gdb process. So, 31-bit inferior ends up with 64-bit vdso mapped.
To avoid this problem a new compat_mm flag has been introduced into
mm context. This flag is used in vdso_fault and vdso_mremap instead
of is_compat_task.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The resume code checks if the resume cpu is the same as the suspend cpu.
If not, and if it is also not possible to switch to the suspend cpu, an
error message should be printed and the resume process should be stopped
by loading a disabled wait psw.
The current logic is broken in multiple ways, the message is never printed,
and the disabled wait psw never loaded because the kernel panics before that:
- sam31 and SIGP_SET_ARCHITECTURE to ESA mode is wrong, this will break
on the first 64bit instruction in sclp_early_printk().
- The init stack should be used, but the stack pointer is not set up correctly
(missing aghi %r15,-STACK_FRAME_OVERHEAD).
- __sclp_early_printk() checks the sclp_init_state. If it is not
sclp_init_state_uninitialized, it simply returns w/o printing anything.
In the resumed kernel however, sclp_init_state will never be uninitialized.
This patch fixes those issues by removing the sam31/ESA logic, adding a
correct init stack pointer, and also introducing sclp_early_printk_force()
to allow using sclp_early_printk() even when sclp_init_state is not
uninitialized.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 updates from Martin Schwidefsky:
- A couple of patches for the zcrypt driver:
+ Add two masks to determine which AP cards and queues are host
devices, this will be useful for KVM AP device passthrough
+ Add-on patch to improve the parsing of the new apmask and aqmask
+ Some code beautification
- Second try to reenable the GCC plugins, the first patch set had a
patch to do this but the merge somehow missed this
- Remove the s390 specific GCC version check and use the generic one
- Three patches for kdump, two bug fixes and one cleanup
- Three patches for the PCI layer, one bug fix and two cleanups
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: remove gcc version check (4.3 or newer)
s390/zcrypt: hex string mask improvements for apmask and aqmask.
s390/zcrypt: AP bus support for alternate driver(s)
s390/zcrypt: code beautify
s390/zcrypt: switch return type to bool for ap_instructions_available()
s390/kdump: Remove kzalloc_panic
s390/kdump: Fix memleak in nt_vmcoreinfo
s390/kdump: Make elfcorehdr size calculation ABI compliant
s390/pci: remove fmb address from debug output
s390/pci: remove stale rc
s390/pci: fix out of bounds access during irq setup
s390/zcrypt: fix ap_instructions_available() returncodes
s390: reenable gcc plugins for real
The ebcdic.c file contains tables for converting between ebcdic and PC
codepage 437. I could however not identify which encoding was used for
the comments. This seems to be some variation of ISO_8859-1 with
non-UTF-8 escape characters.
I have converted this to UTF-8 by manually removing the escape
characters and then running it through recode, to get the same encoding
that we use for the rest of the kernel.
Link: http://lkml.kernel.org/r/20180724111600.4158975-2-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull core signal handling updates from Eric Biederman:
"It was observed that a periodic timer in combination with a
sufficiently expensive fork could prevent fork from every completing.
This contains the changes to remove the need for that restart.
This set of changes is split into several parts:
- The first part makes PIDTYPE_TGID a proper pid type instead
something only for very special cases. The part starts using
PIDTYPE_TGID enough so that in __send_signal where signals are
actually delivered we know if the signal is being sent to a a group
of processes or just a single process.
- With that prep work out of the way the logic in fork is modified so
that fork logically makes signals received while it is running
appear to be received after the fork completes"
* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits)
signal: Don't send signals to tasks that don't exist
signal: Don't restart fork when signals come in.
fork: Have new threads join on-going signal group stops
fork: Skip setting TIF_SIGPENDING in ptrace_init_task
signal: Add calculate_sigpending()
fork: Unconditionally exit if a fatal signal is pending
fork: Move and describe why the code examines PIDNS_ADDING
signal: Push pid type down into complete_signal.
signal: Push pid type down into __send_signal
signal: Push pid type down into send_signal
signal: Pass pid type into do_send_sig_info
signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task
signal: Pass pid type into group_send_sig_info
signal: Pass pid and pid type into send_sigqueue
posix-timers: Noralize good_sigevent
signal: Use PIDTYPE_TGID to clearly store where file signals will be sent
pid: Implement PIDTYPE_TGID
pids: Move the pgrp and session pid pointers from task_struct to signal_struct
kvm: Don't open code task_pid in kvm_vcpu_ioctl
pids: Compute task_tgid using signal->leader_pid
...
git commit cafa0010cd ("Raise the minimum required gcc version to 4.6")
raised the minimum gcc version to 4.6. Therefore remove the s390 specific
gcc 4.3 version check, which wasn't sufficient anyway.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- Restructure of lockdep and latency tracers
This is the biggest change. Joel Fernandes restructured the hooks
from irqs and preemption disabling and enabling. He got rid of
a lot of the preprocessor #ifdef mess that they caused.
He turned both lockdep and the latency tracers to use trace events
inserted in the preempt/irqs disabling paths. But unfortunately,
these started to cause issues in corner cases. Thus, parts of the
code was reverted back to where lockde and the latency tracers
just get called directly (without using the trace events).
But because the original change cleaned up the code very nicely
we kept that, as well as the trace events for preempt and irqs
disabling, but they are limited to not being called in NMIs.
- Have trace events use SRCU for "rcu idle" calls. This was required
for the preempt/irqs off trace events. But it also had to not
allow them to be called in NMI context. Waiting till Paul makes
an NMI safe SRCU API.
- New notrace SRCU API to allow trace events to use SRCU.
- Addition of mcount-nop option support
- SPDX headers replacing GPL templates.
- Various other fixes and clean ups.
- Some fixes are marked for stable, but were not fully tested
before the merge window opened.
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Merge tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
- Restructure of lockdep and latency tracers
This is the biggest change. Joel Fernandes restructured the hooks
from irqs and preemption disabling and enabling. He got rid of a lot
of the preprocessor #ifdef mess that they caused.
He turned both lockdep and the latency tracers to use trace events
inserted in the preempt/irqs disabling paths. But unfortunately,
these started to cause issues in corner cases. Thus, parts of the
code was reverted back to where lockdep and the latency tracers just
get called directly (without using the trace events). But because the
original change cleaned up the code very nicely we kept that, as well
as the trace events for preempt and irqs disabling, but they are
limited to not being called in NMIs.
- Have trace events use SRCU for "rcu idle" calls. This was required
for the preempt/irqs off trace events. But it also had to not allow
them to be called in NMI context. Waiting till Paul makes an NMI safe
SRCU API.
- New notrace SRCU API to allow trace events to use SRCU.
- Addition of mcount-nop option support
- SPDX headers replacing GPL templates.
- Various other fixes and clean ups.
- Some fixes are marked for stable, but were not fully tested before
the merge window opened.
* tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
tracing: Fix SPDX format headers to use C++ style comments
tracing: Add SPDX License format tags to tracing files
tracing: Add SPDX License format to bpf_trace.c
blktrace: Add SPDX License format header
s390/ftrace: Add -mfentry and -mnop-mcount support
tracing: Add -mcount-nop option support
tracing: Avoid calling cc-option -mrecord-mcount for every Makefile
tracing: Handle CC_FLAGS_FTRACE more accurately
Uprobe: Additional argument arch_uprobe to uprobe_write_opcode()
Uprobes: Simplify uprobe_register() body
tracepoints: Free early tracepoints after RCU is initialized
uprobes: Use synchronize_rcu() not synchronize_sched()
tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister()
ftrace: Remove unused pointer ftrace_swapper_pid
tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage"
tracing/irqsoff: Handle preempt_count for different configs
tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage"
tracing: irqsoff: Account for additional preempt_disable
trace: Use rcu_dereference_raw for hooks from trace-event subsystem
tracing/kprobes: Fix within_notrace_func() to check only notrace functions
...
For this function there are only two users, when 1) the elfcorehdr and 2)
the vmcoreinfo is allocated. However a missing vmcoreinfo is not critical
for kdump. So panicking when it cannot be allocated is not required.
Remove kzalloc_panic and adjust its callers accordingly.
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
The vmcoreinfo of a crashed system is potentially fragmented. Thus the
crash kernel has an intermediate step where the vmcoreinfo is copied into a
temporary, continuous buffer in the crash kernel memory. This temporary
buffer is never freed. Free it now to prevent the memleak.
While at it replace all occurrences of "VMCOREINFO" by its corresponding
macro to prevent potential renaming issues.
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
There are two ways to pass the vmcoreinfo to the crash kernel 1) via the
os_info mechanism and 2) via the lowcore->vmcore_info field. In the Linux
kernel only the second way is used. However, the first way is ABI for
stand-alone kdump. So other OSes use it to pass additional debug info. Make
the elfcorehdr size calculation aware of both possible ways.
Fixes: 8cce437fbb ("s390/kdump: Fix elfcorehdr size calculation")
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Linus Torvalds