Introduce two copy functions for the memory of the dumped system,
copy_oldmem_kernel() to copy to the virtual kernel address space
and copy_oldmem_user() to copy to user space.
Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The s390 architecture can store the CPU registers of the crashed system
after the kdump kernel has been started and this is the preferred way.
Remove the remaining code fragments that deal with storing CPU registers
while the crashed system is still active.
Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There is no known user, therefore remove the code.
Acked-by: Rob Van Der Heij <robvdheij@nl.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Passes mlock2-tests test case in 64 bit and compat mode.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove dead code, since this could only happen on a 31 bit machine
where the kernel wouldn't IPL.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
commit 1f6b83e5e4 ("s390: avoid z13 cache aliasing") checks for the
machine type to optimize address space randomization and zero page
allocation to avoid cache aliases.
This check might fail under a hypervisor with migration support.
z/VMs "Single System Image and Live Guest Relocation" facility will
"fake" the machine type of the oldest system in the group. For example
in a group of zEC12 and Z13 the guest appears to run on a zEC12
(architecture fencing within the relocation domain)
Remove the machine type detection and always use cache aliasing
rules that are known to work for all machines. These are the z13
aliasing rules.
Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There's no reason to clear all PSW mask bits other than the addressing
mode bits. Just use the previous PSW mask as-is.
Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Allow to ipl from CCW based devices residing in any subchannel set.
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The input buffer in reipl_fcp_scpdata_write is accessed out of bounds
when an offset is specified. The problem is that the offset refers to
the data we should write to and not to the buffer we read from.
So instead of
memcpy(scp_data, buf + off, count);
we could just do
memcpy(scp_data + off, buf, count);
However we not only modify the data but also store its length. For this to
work we'd need to remember a state per open FH. Since that's not possible
with sysfs callbacks let's just fail when an offset is specified.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Documentation/trace/tracepoints.txt states that the naming scheme
for tracepoints is "subsys_event" to avoid collisions. Rename
the 'diagnose' tracepoint to 's390_diagnose'.
Reported-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
startup calls the C function _sclp_print_early() if the machine we're
running on is not supported by the kernel. sclp.c is getting built
with -m64, so _sclp_print_early() expects the zSeries ELF ABI to be
used.
We previously called _sclp_print_early() using the S/390 ELF ABI, with
a stack frame size of 96 bytes and while being in 31-bit address
mode. This caused _sclp_wait_int() (called indirectly from
_sclp_print_early()) to jump to an undefined address. While
_sclp_wait_int() contained some code to deal with being called in
31-bit addressing mode, it didn't quite work. While fixing this is
possible, the code would still only work by chance and could break any
time.
Ensure compliance with the zSeries ELF ABI by switching to 64-bit
addressing mode early and using a minimum stack frame size of 160
bytes.
Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 updates from Martin Schwidefsky:
"There is only one new feature in this pull for the 4.4 merge window,
most of it is small enhancements, cleanup and bug fixes:
- Add the s390 backend for the software dirty bit tracking. This
adds two new pgtable functions pte_clear_soft_dirty and
pmd_clear_soft_dirty which is why there is a hit to
arch/x86/include/asm/pgtable.h in this pull request.
- A series of cleanup patches for the AP bus, this includes the
removal of the support for two outdated crypto cards (PCICC and
PCICA).
- The irq handling / signaling on buffer full in the runtime
instrumentation code is dropped.
- Some micro optimizations: remove unnecessary memory barriers for a
couple of functions: [smb_]rmb, [smb_]wmb, atomics, bitops, and for
spin_unlock. Use the builtin bswap if available and make
test_and_set_bit_lock more cache friendly.
- Statistics and a tracepoint for the diagnose calls to the
hypervisor.
- The CPU measurement facility support to sample KVM guests is
improved.
- The vector instructions are now always enabled for user space
processes if the hardware has the vector facility. This simplifies
the FPU handling code. The fpu-internal.h header is split into fpu
internals, api and types just like x86.
- Cleanup and improvements for the common I/O layer.
- Rework udelay to solve a problem with kprobe. udelay has busy loop
semantics but still uses an idle processor state for the wait"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (66 commits)
s390: remove runtime instrumentation interrupts
s390/cio: de-duplicate subchannel validation
s390/css: unneeded initialization in for_each_subchannel
s390/Kconfig: use builtin bswap
s390/dasd: fix disconnected device with valid path mask
s390/dasd: fix invalid PAV assignment after suspend/resume
s390/dasd: fix double free in dasd_eckd_read_conf
s390/kernel: fix ptrace peek/poke for floating point registers
s390/cio: move ccw_device_stlck functions
s390/cio: move ccw_device_call_handler
s390/topology: reduce per_cpu() invocations
s390/nmi: reduce size of percpu variable
s390/nmi: fix terminology
s390/nmi: remove casts
s390/nmi: remove pointless error strings
s390: don't store registers on disabled wait anymore
s390: get rid of __set_psw_mask()
s390/fpu: split fpu-internal.h into fpu internals, api, and type headers
s390/dasd: fix list_del corruption after lcu changes
s390/spinlock: remove unneeded serializations at unlock
...
The external interrupts for runtime instrumentation buffer-full
and runtime instrumentation halted are unused and have no current
user. Remove the support and ignore the second parameter of the
s390_runtime_instr system call from now on.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
git commit 155e839a81
"s390/kernel: dynamically allocate FP register save area"
introduced a regression in regard to ptrace.
If the vector register extension is not present or unused the
ptrace peek of a floating pointer register return incorrect data
and the ptrace poke to a floating pointer register overwrites the
task structure starting at task->thread.fpu.fprs.
Cc: stable@kernel.org # v4.3
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Each per_cpu() invocation generates extra code. Since there are a lot
of similiar calls in the topology code we can avoid a lot of them.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change the flag fields within struct mcck_struct to simple bit fields
to reduce the size of the structure which is used as percpu variable.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
According to the architecture registers are validated and not
revalidated. So change comments and functions names to match.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove all the casts to and from the machine check interruption code.
This patch changes struct mci to a union, which contains an anonymous
structure with the already known bits and in addition an unsigned
long field, which contains the raw machine check interruption code.
This allows to simply assign and decoce the interruption code value
without the need for all those casts we had all the time.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
s390_handle_damage() has character string parameter which was used as
a pointer to verbose error message. The hope was (a lot of years ago)
when analyzing dumps that register R2 would still contain the pointer
and therefore it would be rather easy to tell what went wrong.
However gcc optimizes the strings away since a long time. And even if
it wouldn't it is necessary to have a close look at the machine check
interruption code to tell what's wrong.
So remove the pointless error strings.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Split the API and FPU type definitions into separate header files
similar to "x86/fpu: Rename fpu-internal.h to fpu/internal.h" (78f7f1e54b).
The new header files and their meaning are:
asm/fpu/types.h:
FPU related data types, needed for 'struct thread_struct' and
'struct task_struct'.
asm/fpu/api.h:
FPU related 'public' functions for other subsystems and device
drivers.
asm/fpu/internal.h:
FPU internal functions mainly used to convert
FPU register contents in signal handling.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The first level machine check handler for etr and stp machine checks may
call queue_work() while in nmi context. This may deadlock e.g. if the
machine check happened when the interrupted context did hold a lock, that
also will be acquired by queue_work().
Therefore split etr and stp machine check handling into first and second
level handling. The second level handling will then issue the queue_work()
call in process context which avoids the potential deadlock.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When using systemtap it was observed that our udelay implementation is
rather suboptimal if being called from a kprobe handler installed by
systemtap.
The problem observed when a kprobe was installed on lock_acquired().
When the probe was hit the kprobe handler did call udelay, which set
up an (internal) timer and reenabled interrupts (only the clock comparator
interrupt) and waited for the interrupt.
This is an optimization to avoid that the cpu is busy looping while waiting
that enough time passes. The problem is that the interrupt handler still
does call irq_enter()/irq_exit() which then again can lead to a deadlock,
since some accounting functions may take locks as well.
If one of these locks is the same, which caused lock_acquired() to be
called, we have a nice deadlock.
This patch reworks the udelay code for the interrupts disabled case to
immediately leave the low level interrupt handler when the clock
comparator interrupt happens. That way no C code is being called and the
deadlock cannot happen anymore.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The program parameter can be used to mark hardware samples with
some token. Previously, it was used to mark guest samples only.
Improve the program parameter doubleword by combining two parts,
the leftmost LPP part and the rightmost PID part. Set the PID
part for processes by using the task PID.
To distinguish host and guest samples for the kernel (PID part
is zero), the guest must always set the program paramater to a
non-zero value. Use the leftmost bit in the LPP part of the
program parameter to be able to detect guest kernel samples.
[brueckner@linux.vnet.ibm.com]: Split __LC_CURRENT and introduced
__LC_LPP. Corrected __LC_CURRENT users and adjusted assembler parts.
And updated the commit message accordingly.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The use of OFFSET instead of DEFINE makes the definitions in asm-offsets.c
more readable. While we are at it sort the defines for struct _lowcore
according to the field order and remove some unneeded defines.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Various functions in entry.S perform test-under-mask instructions
to test for particular bits in memory. Because test-under-mask uses
a mask value of one byte, the mask value and the offset into the
memory must be calculated manually. This easily introduces errors
and is hard to review and read.
Introduce the TSTMSK assembler macro to specify a mask constant and
let the macro calculate the offset and the byte mask to generate a
test-under-mask instruction. The benefit is that existing symbolic
constants can now be used for tests. Also the macro checks for
zero mask values and mask values that consist of multiple bytes.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Previously, the init task did not have an allocated FPU save area and
saving an FPU state was not possible. Now if the vector extension is
always enabled, provide a static FPU save area to save FPU states of
vector instructions that can be executed quite early.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the kernel detects that the s390 hardware supports the vector
facility, it is enabled by default at an early stage. To force
it off, use the novx kernel parameter. Note that there is a small
time window, where the vector facility is enabled before it is
forced to be off.
With enabling the vector facility by default, the FPU save and
restore functions can be improved. They do not longer require
to manage expensive control register updates to enable or disable
the vector enablement control for particular processes.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
To be able to analyse problems in regard to hypervisor overhead
add a tracepoing for diagnose calls. It reports the number of
the diagnose issued, e.g.
sshd-1385 [002] .... 42.701431: diagnose: nr=0x9c
<idle>-0 [001] ..s. 43.587528: diagnose: nr=0x9c
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce /sys/debug/kernel/diag_stat with a statistic how many diagnose
calls have been done by each CPU in the system.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The <linux/memblock.h> already provides for_each_mem_range() macro that
iterates through memblock areas from type_a and not included in type_b.
We can remove custom for_each_dump_mem_range() macro and use the
for_each_mem_range() instead.
Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
By definition smp_wmb only orders writes against writes. (Finish all
previous writes, and do not start any future write). To protect the
vdso init code against early reads on other CPUs, let's use a full
smp_mb at the end of vdso init. As right now smp_wmb is implemented
as full serialization, this needs no stable backport, but this change
will be necessary if we reimplement smp_wmb.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The calculation for the SMT scaling factor for a hardware thread
which has been partially idle needs to disregard the cycles spent
by the other threads of the core while the thread is idle.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
As discussed on linux-arch all architectures should wire up the separate
system calls that are hidden behind the socketcall multiplexer system call.
It's just a couple more system calls and gives us a very small performance
improvement.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A couple of compat wrapper functions are simply trampolines to the real
system call. This happened because the compat wrapper defines will only
sign and zero extend system call parameters which are of different size
on s390/s390x (longs and pointers).
All other parameters will be correctly sign and zero extended by the
normal system call wrappers.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add notrace to the compat wrapper define to disable tracing of compat
wrapper functions. These are supposed to be very small and more or less
just a trampoline to the real system call.
Also fix indentation.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The scaled cputime is supposed to be derived from the normal per-thread
cputime by dividing it with the average thread density in the last interval.
The calculation of the scaling values for the average thread density is
incorrect. The current, incorrect calculation:
Ci = cycle count with i active threads
T = unscaled cputime, sT = scaled cputime
sT = T * (C1 + C2 + ... + Cn) / (1*C1 + 2*C2 + ... + n*Cn)
The calculation happens to yield the correct numbers for the simple cases
with only one Ci value not zero. But for cases with multiple Ci values not
zero it fails. E.g. on a SMT-2 system with one thread active half the time
and two threads active for the other half of the time it fails, the scaling
factor should be 3/4 but the formula gives 2/3.
The correct formula is
sT = T * (C1/1 + C2/2 + ... + Cn/n) / (C1 + C2 + ... + Cn)
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Previously, the cpum_cf PMU returned -EPERM if a counter is requested and
the counter set to which the counter belongs is not authorized. According
to the perf_event_open() system call manual, an error code of EPERM indicates
an unsupported exclude setting or CAP_SYS_ADMIN is missing.
Use ENOENT to indicate that particular counters are not available when the
counter set which contains the counter is not authorized. For generic events,
this might trigger a fall back, for example, to a software event.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The uc_sigmask in the ucontext structure is an array of words to keep
the 64 signal bits (or 1024 if you ask glibc but the kernel sigset_t
only has 64 bits).
For 64 bit the sigset_t contains a single 8 byte word, but for 31 bit
there are two 4 byte words. The compat signal handler code uses a
simple copy of the 64 bit sigset_t to the 31 bit compat_sigset_t.
As s390 is a big-endian architecture this is incorrect, the two words
in the 31 bit sigset_t array need to be swapped.
Cc: <stable@vger.kernel.org>
Reported-by: Stefan Liebler <stli@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The critical section cleanup code misses to add the offset of the
thread_struct to the task address.
Therefore, if the critical section code gets executed, it may corrupt
the task struct or restore the contents of the floating point registers
from the wrong memory location.
Fixes d0164ee20d "s390/kernel: remove save_fpu_regs() parameter and use
__LC_CURRENT instead".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The swsusp_arch_suspend()/swsusp_arch_resume() functions currently only
save and restore the floating point registers. If the task that started
the hibernation process is using vector registers they can get lost.
To fix this just call save_fpu_regs in swsusp_arch_suspend(), the restore
will happen automatically on return to user space.
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We currently use PERF_EVENT_TXN flag to determine if we are in the middle
of a transaction. If in a transaction, we defer the schedulability checks
from pmu->add() operation to the pmu->commit() operation.
Now that we have "transaction types" (PERF_PMU_TXN_ADD, PERF_PMU_TXN_READ)
we can use the type to determine if we are in a transaction and drop the
PERF_EVENT_TXN flag.
When PERF_EVENT_TXN is dropped, the cpuhw->group_flag on some architectures
becomes unused, so drop that field as well.
This is an extension of the Powerpc patch from Peter Zijlstra to s390,
Sparc and x86 architectures.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1441336073-22750-11-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently, the PMU interface allows reading only one counter at a time.
But some PMUs like the 24x7 counters in Power, support reading several
counters at once. To leveage this functionality, extend the transaction
interface to support a "transaction type".
The first type, PERF_PMU_TXN_ADD, refers to the existing transactions,
i.e. used to _schedule_ all the events on the PMU as a group. A second
transaction type, PERF_PMU_TXN_READ, will be used in a follow-on patch,
by the 24x7 counters to read several counters at once.
Extend the transaction interfaces to the PMU to accept a 'txn_flags'
parameter and use this parameter to ignore any transactions that are
not of type PERF_PMU_TXN_ADD.
Thanks to Peter Zijlstra for his input.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
[peterz: s390 compile fix]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1441336073-22750-3-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull locking and atomic updates from Ingo Molnar:
"Main changes in this cycle are:
- Extend atomic primitives with coherent logic op primitives
(atomic_{or,and,xor}()) and deprecate the old partial APIs
(atomic_{set,clear}_mask())
The old ops were incoherent with incompatible signatures across
architectures and with incomplete support. Now every architecture
supports the primitives consistently (by Peter Zijlstra)
- Generic support for 'relaxed atomics':
- _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return()
- atomic_read_acquire()
- atomic_set_release()
This came out of porting qwrlock code to arm64 (by Will Deacon)
- Clean up the fragile static_key APIs that were causing repeat bugs,
by introducing a new one:
DEFINE_STATIC_KEY_TRUE(name);
DEFINE_STATIC_KEY_FALSE(name);
which define a key of different types with an initial true/false
value.
Then allow:
static_branch_likely()
static_branch_unlikely()
to take a key of either type and emit the right instruction for the
case. To be able to know the 'type' of the static key we encode it
in the jump entry (by Peter Zijlstra)
- Static key self-tests (by Jason Baron)
- qrwlock optimizations (by Waiman Long)
- small futex enhancements (by Davidlohr Bueso)
- ... and misc other changes"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits)
jump_label/x86: Work around asm build bug on older/backported GCCs
locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations
locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h
locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics
locking/qrwlock: Implement queue_write_unlock() using smp_store_release()
locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition
locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t'
locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic
locking/static_keys: Make verify_keys() static
jump label, locking/static_keys: Update docs
locking/static_keys: Provide a selftest
jump_label: Provide a self-test
s390/uaccess, locking/static_keys: employ static_branch_likely()
x86, tsc, locking/static_keys: Employ static_branch_likely()
locking/static_keys: Add selftest
locking/static_keys: Add a new static_key interface
locking/static_keys: Rework update logic
locking/static_keys: Add static_key_{en,dis}able() helpers
...
Pull timer updates from Thomas Gleixner:
"Rather large, but nothing exiting:
- new range check for settimeofday() to prevent that boot time
becomes negative.
- fix for file time rounding
- a few simplifications of the hrtimer code
- fix for the proc/timerlist code so the output of clock realtime
timers is accurate
- more y2038 work
- tree wide conversion of clockevent drivers to the new callbacks"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (88 commits)
hrtimer: Handle failure of tick_init_highres() gracefully
hrtimer: Unconfuse switch_hrtimer_base() a bit
hrtimer: Simplify get_target_base() by returning current base
hrtimer: Drop return code of hrtimer_switch_to_hres()
time: Introduce timespec64_to_jiffies()/jiffies_to_timespec64()
time: Introduce current_kernel_time64()
time: Introduce struct itimerspec64
time: Add the common weak version of update_persistent_clock()
time: Always make sure wall_to_monotonic isn't positive
time: Fix nanosecond file time rounding in timespec_trunc()
timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers
cris/time: Migrate to new 'set-state' interface
kernel: broadcast-hrtimer: Migrate to new 'set-state' interface
xtensa/time: Migrate to new 'set-state' interface
unicore/time: Migrate to new 'set-state' interface
um/time: Migrate to new 'set-state' interface
sparc/time: Migrate to new 'set-state' interface
sh/localtimer: Migrate to new 'set-state' interface
score/time: Migrate to new 'set-state' interface
s390/time: Migrate to new 'set-state' interface
...
Pull s390 updates from Martin Schwidefsky:
"The big one is support for fake NUMA, splitting a really large machine
in more manageable piece improves performance in some cases, e.g. for
a KVM host.
The FICON Link Incident handling has been improved, this helps the
operator to identify degraded or non-operational FICON connections.
The save and restore of floating point and vector registers has been
overhauled to allow the future use of vector registers in the kernel.
A few small enhancement, magic sys-requests for the vt220 console via
SCLP, some more assembler code has been converted to C, the PCI error
handling is improved.
And the usual cleanup and bug fixing"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (59 commits)
s390/jump_label: Use %*ph to print small buffers
s390/sclp_vt220: support magic sysrequests
s390/ctrlchar: improve handling of magic sysrequests
s390/numa: remove superfluous ARCH_WANT defines
s390/3270: redraw screen on unsolicited device end
s390/dcssblk: correct out of bounds array indexes
s390/mm: simplify page table alloc/free code
s390/pci: move debug messages to debugfs
s390/nmi: initialize control register 0 earlier
s390/zcrypt: use msleep() instead of mdelay()
s390/hmcdrv: fix interrupt registration
s390/setup: fix novx parameter
s390/uaccess: remove uaccess_primary kernel parameter
s390: remove unneeded sizeof(void *) comparisons
s390/facilities: remove transactional-execution bits
s390/numa: re-add DIE sched_domain_topology_level
s390/dasd: enhance CUIR scope detection
s390/dasd: fix failing path verification
s390/vdso: emit a GNU hash
s390/numa: make core to node mapping data dynamic
...
s390: timekeeping changes, cleanups and fixes
x86: support for Hyper-V MSRs to report crashes, and a bunch of cleanups.
One interesting feature that was planned for 4.3 (emulating the local
APIC in kernel while keeping the IOAPIC and 8254 in userspace) had to
be delayed because Intel complained about my reading of the manual.
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Merge tag 'kvm-4.3-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"A very small release for x86 and s390 KVM.
- s390: timekeeping changes, cleanups and fixes
- x86: support for Hyper-V MSRs to report crashes, and a bunch of
cleanups.
One interesting feature that was planned for 4.3 (emulating the local
APIC in kernel while keeping the IOAPIC and 8254 in userspace) had to
be delayed because Intel complained about my reading of the manual"
* tag 'kvm-4.3-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (42 commits)
x86/kvm: Rename VMX's segment access rights defines
KVM: x86/vPMU: Fix unnecessary signed extension for AMD PERFCTRn
kvm: x86: Fix error handling in the function kvm_lapic_sync_from_vapic
KVM: s390: Fix assumption that kvm_set_irq_routing is always run successfully
KVM: VMX: drop ept misconfig check
KVM: MMU: fully check zero bits for sptes
KVM: MMU: introduce is_shadow_zero_bits_set()
KVM: MMU: introduce the framework to check zero bits on sptes
KVM: MMU: split reset_rsvds_bits_mask_ept
KVM: MMU: split reset_rsvds_bits_mask
KVM: MMU: introduce rsvd_bits_validate
KVM: MMU: move FNAME(is_rsvd_bits_set) to mmu.c
KVM: MMU: fix validation of mmio page fault
KVM: MTRR: Use default type for non-MTRR-covered gfn before WARN_ON
KVM: s390: host STP toleration for VMs
KVM: x86: clean/fix memory barriers in irqchip_in_kernel
KVM: document memory barriers for kvm->vcpus/kvm->online_vcpus
KVM: x86: remove unnecessary memory barriers for shared MSRs
KVM: move code related to KVM_SET_BOOT_CPU_ID to x86
KVM: s390: log capability enablement and vm attribute changes
...
printk() supports %*ph format specifier for printing a small buffers,
let's use it intead of %02x %02x...
Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change machine_check_init() to an early_initcall(). This makes sure it will
be called before all other cpus are online and therfore saves us a lot of
pointless smp_call_function() calls.
The control register settings will be forwarded to the other cpus when they
will be brought online.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The novx parameter disables the vector facility but the HWCAP_S390_VXRS
bit in the ELf hardware capabilies is always set if the machine has
the vector facility. If the user space program uses the "vx" string
in the features field of /proc/cpuinfo to utilize vector instruction
it will crash if the novx kernel paramter is set.
Convert setup_hwcaps to an arch_initcall and use MACHINE_HAS_VX to
decide if the HWCAPS_S390_VXRS bit needs to be set.
Cc: stable@vger.kernel.org # 3.18+
Reported-by: Ulrich Weigand <uweigand@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the two facility bits
50 - constrained transactional-execution facility
74 - transactional-execution facility
from the required facilities if the kernel is built with -march=zEC12.
E.g. z/VM 6.3 doesn't virtualize the TX facility yet. Therefore a kernel
built with -march=zEC12 and ipl'ed on a zEC12 machine as a z/VM 6.3 guest
will emit a message about the missing facilities and stop working.
The kernel however doesn't make use of the TX facility, therefore remove
the two TX related facility bits and fix this unpleasant behavior.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
By accident this level has been removed by the NUMA infrastructure patch.
For non-NUMA systems with CPUs that span more than one book, this makes
the scheduler only use one of the books and the other books remain idle.
Fix this and re-add the missing level.
For NUMA and non-NUMA we have the following scheduling domains and groups:
- SMT (Groups: CPU threads)
- MC (Groups: Cores)
- BOOK (Groups: Books)
For the non-NUMA case we have one last level scheduling domain:
- DIE (Groups: Whole system, has all CPUs -> cpu_cpu_mask)
For the NUMA case we have the following two last level scheduling domains:
- DIE (Groups: NUMA nodes -> cpu_cpu_mask -> returns node siblings)
- NUMA (Groups: Whole system, has all CPUs -> created in sched_init_numa())
Fixes: e8054b654b ("s390/numa: add topology tree infrastructure")
Reported-and-tested-by: Evgeny Cherkashin <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Migrate s390 driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.
This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.
We weren't doing anything in the ->set_mode() callback. So, this patch
doesn't provide any set-state callbacks.
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
As proposed by Andy Lutomirski create the SysV and the GNU hash
for the vdso objects. This may make some dynamic loaders a bit
faster.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since we are already protected by the "sched_domains_mutex" lock, we can
safely remove the topology lock.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the host has STP enabled, the TOD of the host will be changed during
synchronization phases. These are performed during a stop_machine() call.
As the guest TOD is based on the host TOD, we have to make sure that:
- no VCPU is in the SIE (implicitly guaranteed via stop_machine())
- manual guest TOD calculations are not affected
"Epoch" is the guest TOD clock delta to the host TOD clock. We have to
adjust that value during the STP synchronization and make sure that code
that accesses the epoch won't get interrupted in between (via disabling
preemption).
Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The MT scaling values are updated on each calll to do_account_vtime.
This function is called for each HZ interrupt and for each context
switch. Context switch can happen often, the STCCTM instruction
on this path is noticeable. Limit the updates to once per jiffy.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Enable core NUMA support for s390 and add one simple default mode "plain"
that creates one single NUMA node.
This patch contains several changes from Michael Holzheu.
Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since we've already stepped away from ENABLE is a JMP and DISABLE is a
NOP with the branch_default bits, and are going to make it even worse,
rename it to make it all clearer.
This way we don't mix multiple levels of logic attributes, but have a
plain 'physical' name for what the current instruction patching status
of a jump label is.
This is a first step in removing the naming confusion that has led to
a stream of avoidable bugs such as:
a833581e37 ("x86, perf: Fix static_key bug in load_mm_cr4()")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
[ Beefed up the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Right now we use the address of the sie control block as tag for
the sampling data. This is hard to get for users. Let's just use
the PID of the cpu thread to mark the hardware samples.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
All calls to save_fpu_regs() specify the fpu structure of the current task
pointer as parameter. The task pointer of the current task can also be
retrieved from the CPU lowcore directly. Remove the parameter definition,
load the __LC_CURRENT task pointer from the CPU lowcore, and rebase the FPU
structure onto the task structure. Apply the same approach for the
load_fpu_regs() function.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Section mismatch in reference from the function __smp_store_cpu_state()
to the function .init.text:memblock_alloc()
The function __smp_store_cpu_state() references
the function __init memblock_alloc().
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The 31-bit assembler code for the early sclp console is error
prone as git commit fde24b54d976cc123506695c17db01438a11b673
"s390/sclp: clear upper register halves in _sclp_print_early"
has shown.
Convert the assembler code to C.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Replace the deprecated atomic_{set,clear}_mask() usage with the now
ubiquous atomic_{or,andnot}() functions.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If a machine checks is received while the CPU is in the kernel, only
the s390_do_machine_check function will be called. The call to
s390_handle_mcck is postponed until the CPU returns to user space.
Because of this it is safe to use the asynchronous stack for machine
checks even if the CPU is already handling an interrupt.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reorder the instructions of UPDATE_VTIME to improve superscalar execution,
remove duplicate checks for problem-state from the asynchronous interrupt
handlers, and move the check for problem-state from the synchronous
exit path to the program check path as it is only needed for program
checks inside the kernel.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently there are two mechanisms to deal with cleanup work due to
interrupts. The HANDLE_SIE_INTERCEPT macro is used to undo the changes
required to enter SIE in sie64a. If the SIE instruction causes a program
check, or an asynchronous interrupt is received the HANDLE_SIE_INTERCEPT
code forwards the program execution to sie_exit.
All the other critical sections in entry.S are handled by the code in
cleanup_critical that is called by the SWITCH_ASYNC macro.
Move the sie64a function to the beginning of the critical section and
add the code from HANDLE_SIE_INTERCEPT to cleanup_critical. Add a special
case for the sie64a cleanup to the program check handler.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The HANDLE_SIE_INTERCEPT macro is used in the interrupt handlers
and the program check handler to undo a few changes done by sie64a.
Among them are guest vs host LPP, the gmap ASCE vs kernel ASCE and
the bit that indicates that SIE is currently running on the CPU.
There is a race of a voluntary SIE exit vs asynchronous interrupts.
If the CPU completed the SIE instruction and the TM instruction of
the LPP macro at the time it receives an interrupt, the interrupt
handler will run while the LPP, the ASCE and the SIE bit are still
set up for guest execution. This might result in wrong sampling data,
but it will not cause data corruption or lockups.
The critical section in sie64a needs to be enlarged to include all
instructions that undo the changes required for guest execution.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add support for the generic CPU feature modalias implementation that wires
up optional CPU features to udev-based module autoprobing.
The <asm/cpufeature.h> file provides definitions to map CPU features to
s390 ELF hardware capabilities.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Improve the save and restore behavior of FPU register contents to use the
vector extension within the kernel.
The kernel does not use floating-point or vector registers and, therefore,
saving and restoring the FPU register contents are performed for handling
signals or switching processes only. To prepare for using vector
instructions and vector registers within the kernel, enhance the save
behavior and implement a lazy restore at return to user space from a
system call or interrupt.
To implement the lazy restore, the save_fpu_regs() sets a CPU information
flag, CIF_FPU, to indicate that the FPU registers must be restored.
Saving and setting CIF_FPU is performed in an atomic fashion to be
interrupt-safe. When the kernel wants to use the vector extension or
wants to change the FPU register state for a task during signal handling,
the save_fpu_regs() must be called first. The CIF_FPU flag is also set at
process switch. At return to user space, the FPU state is restored. In
particular, the FPU state includes the floating-point or vector register
contents, as well as, vector-enablement and floating-point control. The
FPU state restore and clearing CIF_FPU is also performed in an atomic
fashion.
For KVM, the restore of the FPU register state is performed when restoring
the general-purpose guest registers before the SIE instructions is started.
Because the path towards the SIE instruction is interruptible, the CIF_FPU
flag must be checked again right before going into SIE. If set, the guest
registers must be reloaded again by re-entering the outer SIE loop. This
is the same behavior as if the SIE critical section is interrupted.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make the floating-point save area dynamically allocated and uses a flag
to distinguish whether a task uses floating-point or vector registers.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce a new structure to manage FP and VX registers. Refactor the
save and restore of floating point and vector registers with a set
of helper functions in fpu-internal.h.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use the test_fp_ctl() to test the floating-point control word
for validity and use restore_fp_ctl() to set it in load_sigregs.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
git commit 0c8c0f03e3
"x86/fpu, sched: Dynamically allocate 'struct fpu'"
moved the thread_struct to the end of the task_struct.
This causes some of the offsets used in entry.S to overflow their
instruction operand field. To fix this use aghi to create a
dedicated pointer for the thread_struct.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Heiko noticed that the current check for hugepage support on s390 is a
little bit too harsh as systems which do not support will crash.
The reason is that pageblock_order can now get negative when we set
HPAGE_SHIFT to 0. To avoid all this and to avoid opening another can of
worms with enabling HUGETLB_PAGE_SIZE_VARIABLE I think it would be best
to simply allow architectures to define their own hugepages_supported().
Revert bea41197ea ("s390/mm: make hugepages_supported a boot time
decision") in preparation.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull s390 fixes from Martin Schwidefsky:
"One improvement for the zcrypt driver, the quality attribute for the
hwrng device has been missing. Without it the kernel entropy seeding
will not happen automatically.
And six bug fixes, the most important one is the fix for the vector
register corruption due to machine checks"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/nmi: fix vector register corruption
s390/process: fix sfpc inline assembly
s390/dasd: fix kernel panic when alias is set offline
s390/sclp: clear upper register halves in _sclp_print_early
s390/oprofile: fix compile error
s390/sclp: fix compile error
s390/zcrypt: enable s390 hwrng to seed kernel entropy
If a machine check happens, the machine has the vector facility installed
and the extended save area exists, the cpu will save vector register
contents into the extended save area. This is regardless of control
register 0 contents, which enables and disables the vector facility during
runtime.
On each machine check we should validate the vector registers. The current
code however tries to validate the registers only if the running task is
using vector registers in user space.
However even the current code is broken and causes vector register
corruption on machine checks, if user space uses them:
the prefix area contains a pointer (absolute address) to the machine check
extended save area. In order to save some space the save area was put into
an unused area of the second prefix page.
When validating vector register contents the code uses the absolute address
of the extended save area, which is wrong. Due to prefixing the vector
instructions will then access contents using absolute addresses instead
of real addresses, where the machine stored the contents.
If the above would work there is still the problem that register validition
would only happen if user space uses vector registers. If kernel space uses
them also, this may also lead to vector register content corruption:
if the kernel makes use of vector instructions, but the current running
user space context does not, the machine check handler will validate
floating point registers instead of vector registers.
Given the fact that writing to a floating point register may change the
upper halve of the corresponding vector register, we also experience vector
register corruption in this case.
Fix all of these issues, and always validate vector registers on each
machine check, if the machine has the vector facility installed and the
extended save area is defined.
Cc: <stable@vger.kernel.org> # 4.1+
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The sfpc inline assembly within execve_tail() may incorrectly set bits
28-31 of the sfpc instruction to a value which is not zero.
These bits however are currently unused and therefore should be zero
so we won't get surprised if these bits will be used in the future.
Therefore remove the second operand from the inline assembly.
Cc: <stable@vger.kernel.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the kernel is compiled with gcc 5.1 and the XZ compression option
the decompress_kernel function calls _sclp_print_early in 64-bit mode
while the content of the upper register half of %r6 is non-zero.
This causes a specification exception on the servc instruction in
_sclp_servc.
The _sclp_print_early function saves and restores the upper registers
halves but it fails to clear them for the 31-bit code of the mini sclp
driver.
Cc: <stable@vger.kernel.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
speed module address lookup. He found some abusers of the module lock
doing that too.
A little bit of parameter work here too; including Dan Streetman's breaking
up the big param mutex so writing a parameter can load another module (yeah,
really). Unfortunately that broke the usual suspects, !CONFIG_MODULES and
!CONFIG_SYSFS, so those fixes were appended too.
Cheers,
Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module updates from Rusty Russell:
"Main excitement here is Peter Zijlstra's lockless rbtree optimization
to speed module address lookup. He found some abusers of the module
lock doing that too.
A little bit of parameter work here too; including Dan Streetman's
breaking up the big param mutex so writing a parameter can load
another module (yeah, really). Unfortunately that broke the usual
suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
appended too"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
modules: only use mod->param_lock if CONFIG_MODULES
param: fix module param locks when !CONFIG_SYSFS.
rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
module: add per-module param_lock
module: make perm const
params: suppress unused variable error, warn once just in case code changes.
modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
kernel/module.c: avoid ifdefs for sig_enforce declaration
kernel/workqueue.c: remove ifdefs over wq_power_efficient
kernel/params.c: export param_ops_bool_enable_only
kernel/params.c: generalize bool_enable_only
kernel/module.c: use generic module param operaters for sig_enforce
kernel/params: constify struct kernel_param_ops uses
sysfs: tightened sysfs permission checks
module: Rework module_addr_{min,max}
module: Use __module_address() for module_address_lookup()
module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
module: Optimize __module_address() using a latched RB-tree
rbtree: Implement generic latch_tree
seqlock: Introduce raw_read_seqcount_latch()
...
Pull more s390 updates from Martin Schwidefsky:
"There is one larger patch for the AP bus code to make it work with the
longer reset periods of the latest crypto cards.
A new default configuration, a naming cleanup for SMP and a few fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/kdump: fix compile for !SMP
s390/kdump: fix nosmt kernel parameter
s390: new default configuration
s390/smp: cleanup core vs. cpu in the SCLP interface
s390/smp: fix sigp cpu detection loop
s390/zcrypt: Fixed reset and interrupt handling of AP queues
s390/kdump: fix REGSET_VX_LOW vector register ELF notes
s390/bpf: Fix backward jumps
Fix this compile error:
arch/s390/kernel/setup.c:875:2: error:
implicit declaration of function 'smp_save_dump_cpus'
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
clone has some of the quirkiest syscall handling in the kernel, with a
pile of special cases, historical curiosities, and architecture-specific
calling conventions. In particular, clone with CLONE_SETTLS accepts a
parameter "tls" that the C entry point completely ignores and some
assembly entry points overwrite; instead, the low-level arch-specific
code pulls the tls parameter out of the arch-specific register captured
as part of pt_regs on entry to the kernel. That's a massive hack, and
it makes the arch-specific code only work when called via the specific
existing syscall entry points; because of this hack, any new clone-like
system call would have to accept an identical tls argument in exactly
the same arch-specific position, rather than providing a unified system
call entry point across architectures.
The first patch allows architectures to handle the tls argument via
normal C parameter passing, if they opt in by selecting
HAVE_COPY_THREAD_TLS. The second patch makes 32-bit and 64-bit x86 opt
into this.
These two patches came out of the clone4 series, which isn't ready for
this merge window, but these first two cleanup patches were entirely
uncontroversial and have acks. I'd like to go ahead and submit these
two so that other architectures can begin building on top of this and
opting into HAVE_COPY_THREAD_TLS. However, I'm also happy to wait and
send these through the next merge window (along with v3 of clone4) if
anyone would prefer that.
This patch (of 2):
clone with CLONE_SETTLS accepts an argument to set the thread-local
storage area for the new thread. sys_clone declares an int argument
tls_val in the appropriate point in the argument list (based on the
various CLONE_BACKWARDS variants), but doesn't actually use or pass along
that argument. Instead, sys_clone calls do_fork, which calls
copy_process, which calls the arch-specific copy_thread, and copy_thread
pulls the corresponding syscall argument out of the pt_regs captured at
kernel entry (knowing what argument of clone that architecture passes tls
in).
Apart from being awful and inscrutable, that also only works because only
one code path into copy_thread can pass the CLONE_SETTLS flag, and that
code path comes from sys_clone with its architecture-specific
argument-passing order. This prevents introducing a new version of the
clone system call without propagating the same architecture-specific
position of the tls argument.
However, there's no reason to pull the argument out of pt_regs when
sys_clone could just pass it down via C function call arguments.
Introduce a new CONFIG_HAVE_COPY_THREAD_TLS for architectures to opt into,
and a new copy_thread_tls that accepts the tls parameter as an additional
unsigned long (syscall-argument-sized) argument. Change sys_clone's tls
argument to an unsigned long (which does not change the ABI), and pass
that down to copy_thread_tls.
Architectures that don't opt into copy_thread_tls will continue to ignore
the C argument to sys_clone in favor of the pt_regs captured at kernel
entry, and thus will be unable to introduce new versions of the clone
syscall.
Patch co-authored by Josh Triplett and Thiago Macieira.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thiago Macieira <thiago.macieira@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a potential bug with KVM and hugetlbfs if the hardware does not
support hugepages (EDAT1). We fix this by making EDAT1 a hard requirement
for hugepages and therefore removing and simplifying code.
As s390, with the sw-emulated hugepages, was the only user of
arch_prepare/release_hugepage I also removed theses calls from common and
other architecture code.
This patch (of 5):
By dropping support for hugepages on machines which do not have the
hardware feature EDAT1, we fix a potential s390 KVM bug.
The bug would happen if a guest is backed by hugetlbfs (not supported
currently), but does not get pagetables with PGSTE. This would lead to
random memory overwrites.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It turned out that SIGP set-multi-threading can only be done once.
Therefore switching to a different MT level after switching to
sclp.mtid_prev in the dump case fails.
As a symptom specifying the "nosmt" parameter currently fails for
the kdump kernel and the kernel starts with multi-threading enabled.
So fix this and issue diag 308 subcode 1 call after collecting the
CPU states for the dump. Also enhance the diag308_reset() function to
be usable also with enabled lowcore protection and prefix register != 0.
After the reset it is possible to switch the MT level again. We have
to do the reset very early in order not to kill the already initialized
console. Therefore instead of kmalloc() the corresponding memblock
functions have to be used. To avoid copying the sclp cpu code into
sclp_early, we now use the simple sigp loop method for CPU detection.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The SCLP interface to query, configure and deconfigure CPUs actually
operates on cores. For a machine without the multi-threading faciltiy
a CPU and a core are equivalent but starting with System z13 a core
can have multiple hardware threads, also referred to as logical CPUs.
To avoid confusion replace the word 'cpu' with 'core' in the SCLP
interface. Also replace MAX_CPU_ADDRESS with SCLP_MAX_CORES.
The core-id is an 8-bit field, the maximum thread id is in the range
0-31. The theoretical limit for the CPU address is therefore 8191.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
On a (theoretical) system where the read-cpu-info SCLP command does
not work but SMT is enabled, the sigp detection loop may not find
all configured cores. The maximum CPU address needs to be shifted
with smp_cpu_mt_shift.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The REGSET_VX_LOW ELF notes should contain the lower 64 bit halfes of the
first sixteen 128 bit vector registers. Unfortunately currently we copy
the upper halfes.
Fix this and correctly copy the lower halfes.
Fixes: a62bc07392 ("s390/kdump: add support for vector extension")
Cc: stable@vger.kernel.org # 3.18+
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Some high end Intel Xeon systems report uncorrectable memory errors as a
recoverable machine check. Linux has included code for some time to
process these and just signal the affected processes (or even recover
completely if the error was in a read only page that can be replaced by
reading from disk).
But we have no recovery path for errors encountered during kernel code
execution. Except for some very specific cases were are unlikely to ever
be able to recover.
Enter memory mirroring. Actually 3rd generation of memory mirroing.
Gen1: All memory is mirrored
Pro: No s/w enabling - h/w just gets good data from other side of the
mirror
Con: Halves effective memory capacity available to OS/applications
Gen2: Partial memory mirror - just mirror memory begind some memory controllers
Pro: Keep more of the capacity
Con: Nightmare to enable. Have to choose between allocating from
mirrored memory for safety vs. NUMA local memory for performance
Gen3: Address range partial memory mirror - some mirror on each memory
controller
Pro: Can tune the amount of mirror and keep NUMA performance
Con: I have to write memory management code to implement
The current plan is just to use mirrored memory for kernel allocations.
This has been broken into two phases:
1) This patch series - find the mirrored memory, use it for boot time
allocations
2) Wade into mm/page_alloc.c and define a ZONE_MIRROR to pick up the
unused mirrored memory from mm/memblock.c and only give it out to
select kernel allocations (this is still being scoped because
page_alloc.c is scary).
This patch (of 3):
Add extra "flags" to memblock to allow selection of memory based on
attribute. No functional changes
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Xiexiuqi <xiexiuqi@huawei.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
for silicon that no one owns: these are really new features for
everyone.
* ARM: several features are in progress but missed the 4.2 deadline.
So here is just a smattering of bug fixes, plus enabling the VFIO
integration.
* s390: Some fixes/refactorings/optimizations, plus support for
2GB pages.
* x86: 1) host and guest support for marking kvmclock as a stable
scheduler clock. 2) support for write combining. 3) support for
system management mode, needed for secure boot in guests. 4) a bunch
of cleanups required for 2+3. 5) support for virtualized performance
counters on AMD; 6) legacy PCI device assignment is deprecated and
defaults to "n" in Kconfig; VFIO replaces it. On top of this there are
also bug fixes and eager FPU context loading for FPU-heavy guests.
* Common code: Support for multiple address spaces; for now it is
used only for x86 SMM but the s390 folks also have plans.
There are some x86 conflicts, one with the rc8 pull request and
the rest with Ingo's FPU rework.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull first batch of KVM updates from Paolo Bonzini:
"The bulk of the changes here is for x86. And for once it's not for
silicon that no one owns: these are really new features for everyone.
Details:
- ARM:
several features are in progress but missed the 4.2 deadline.
So here is just a smattering of bug fixes, plus enabling the
VFIO integration.
- s390:
Some fixes/refactorings/optimizations, plus support for 2GB
pages.
- x86:
* host and guest support for marking kvmclock as a stable
scheduler clock.
* support for write combining.
* support for system management mode, needed for secure boot in
guests.
* a bunch of cleanups required for the above
* support for virtualized performance counters on AMD
* legacy PCI device assignment is deprecated and defaults to "n"
in Kconfig; VFIO replaces it
On top of this there are also bug fixes and eager FPU context
loading for FPU-heavy guests.
- Common code:
Support for multiple address spaces; for now it is used only for
x86 SMM but the s390 folks also have plans"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (124 commits)
KVM: s390: clear floating interrupt bitmap and parameters
KVM: x86/vPMU: Enable PMU handling for AMD PERFCTRn and EVNTSELn MSRs
KVM: x86/vPMU: Implement AMD vPMU code for KVM
KVM: x86/vPMU: Define kvm_pmu_ops to support vPMU function dispatch
KVM: x86/vPMU: introduce kvm_pmu_msr_idx_to_pmc
KVM: x86/vPMU: reorder PMU functions
KVM: x86/vPMU: whitespace and stylistic adjustments in PMU code
KVM: x86/vPMU: use the new macros to go between PMC, PMU and VCPU
KVM: x86/vPMU: introduce pmu.h header
KVM: x86/vPMU: rename a few PMU functions
KVM: MTRR: do not map huge page for non-consistent range
KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type
KVM: MTRR: introduce mtrr_for_each_mem_type
KVM: MTRR: introduce fixed_mtrr_addr_* functions
KVM: MTRR: sort variable MTRRs
KVM: MTRR: introduce var_mtrr_range
KVM: MTRR: introduce fixed_mtrr_segment table
KVM: MTRR: improve kvm_mtrr_get_guest_memory_type
KVM: MTRR: do not split 64 bits MSR content
KVM: MTRR: clean up mtrr default type
...
Pull s390 updates from Martin Schwidefsky:
"Pretty boring for a merge window pull.
One change in behaviour is the patch for dasd driver, the module which
provides the diagnose discipline is now loaded automatically.
The SCLP code got a nice cleanup, a new global structure replaces a
bunch of accessor functions.
And a couple of random, small improvements"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/pci: improve handling of hotplug event 0x301
s390/setup: fix DMA_API_DEBUG warnings
s390/zcrypt: remove obsolete __constant
s390/keyboard: avoid off-by-one when using strnlen_user()
s390/sclp: pass timeout as HZ independent value
s390/mm: s/specifiation/specification/, s/an specification/a specification/
s390/sclp: Use DECLARE_BITMAP
s390/dasd: Enable automatic loading of dasd_diag_mod
s390/sclp: move sclp_facilities into "struct sclp"
s390/sclp: get rid of sclp_get_mtid() and sclp_get_mtid_max()
s390/sclp: unify basic sclp access by exposing "struct sclp"
s390/sclp: prepare smp_fill_possible_mask for global "struct sclp"
Addresses from the usable space in [_ehead, _stext] lead to false
positives in DMA_API_DEBUG code (which will complain when an address
is in [_text, _etext]).
Avoid these warnings by not using that memory in case of
CONFIG_DMA_API_DEBUG=y.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Most code already uses consts for the struct kernel_param_ops,
sweep the kernel for the last offending stragglers. Other than
include/linux/moduleparam.h and kernel/params.c all other changes
were generated with the following Coccinelle SmPL patch. Merge
conflicts between trees can be handled with Coccinelle.
In the future git could get Coccinelle merge support to deal with
patch --> fail --> grammar --> Coccinelle --> new patch conflicts
automatically for us on patches where the grammar is available and
the patch is of high confidence. Consider this a feature request.
Test compiled on x86_64 against:
* allnoconfig
* allmodconfig
* allyesconfig
@ const_found @
identifier ops;
@@
const struct kernel_param_ops ops = {
};
@ const_not_found depends on !const_found @
identifier ops;
@@
-struct kernel_param_ops ops = {
+const struct kernel_param_ops ops = {
};
Generated-by: Coccinelle SmPL
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Junio C Hamano <gitster@pobox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: cocci@systeme.lip6.fr
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
As part of addressing the "y2038 problem" for in-kernel uses,
this patch converts read_boot_clock() to read_boot_clock64()
and read_persistent_clock() to read_persistent_clock64() using
timespec64.
Rename some instances of 'timespec' to 'timespec64' in time.c and
related references
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
[jstultz: Fixed minor style and grammer tweaks
pointed out by Ingo]
Signed-off-by: John Stultz <john.stultz@linaro.org>
As all relevant sclp data is now directly accessible, let's move the
logic of these two functions to the single caller.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Let's unify basic access to sclp fields by storing the data in an external
struct in asm/sclp.h.
The values can now directly be accessed by other components, so there is
no need for most accessor functions and external variables anymore.
The mtid, mtid_max and facility part will be cleaned up separately.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We need to rename sclp -> sclp_max to prepare for using the global variable
"sclp" for sclp access later in this function.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
exit_sie_sync is used to kick CPUs out of SIE and prevent reentering at
any point in time. This is used to reload the prefix pages and to
set the IBS stuff in a way that guarantees that after this function
returns we are no longer in SIE. All current users trigger KVM requests.
The request must be set before we block the CPUs to avoid races. Let's
make this implicit by adding the request into a new function
kvm_s390_sync_requests that replaces exit_sie_sync and split out
s390_vcpu_block and s390_vcpu_unblock, that can be used to keep
CPUs out of SIE independent of requests.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Pull exec domain removal from Richard Weinberger:
"This series removes execution domain support from Linux.
The idea behind exec domains was to support different ABIs. The
feature was never complete nor stable. Let's rip it out and make the
kernel signal handling code less complicated"
* 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (27 commits)
arm64: Removed unused variable
sparc: Fix execution domain removal
Remove rest of exec domains.
arch: Remove exec_domain from remaining archs
arc: Remove signal translation and exec_domain
xtensa: Remove signal translation and exec_domain
xtensa: Autogenerate offsets in struct thread_info
x86: Remove signal translation and exec_domain
unicore32: Remove signal translation and exec_domain
um: Remove signal translation and exec_domain
tile: Remove signal translation and exec_domain
sparc: Remove signal translation and exec_domain
sh: Remove signal translation and exec_domain
s390: Remove signal translation and exec_domain
mn10300: Remove signal translation and exec_domain
microblaze: Remove signal translation and exec_domain
m68k: Remove signal translation and exec_domain
m32r: Remove signal translation and exec_domain
m32r: Autogenerate offsets in struct thread_info
frv: Remove signal translation and exec_domain
...
Pull networking updates from David Miller:
1) Add BQL support to via-rhine, from Tino Reichardt.
2) Integrate SWITCHDEV layer support into the DSA layer, so DSA drivers
can support hw switch offloading. From Floria Fainelli.
3) Allow 'ip address' commands to initiate multicast group join/leave,
from Madhu Challa.
4) Many ipv4 FIB lookup optimizations from Alexander Duyck.
5) Support EBPF in cls_bpf classifier and act_bpf action, from Daniel
Borkmann.
6) Remove the ugly compat support in ARP for ugly layers like ax25,
rose, etc. And use this to clean up the neigh layer, then use it to
implement MPLS support. All from Eric Biederman.
7) Support L3 forwarding offloading in switches, from Scott Feldman.
8) Collapse the LOCAL and MAIN ipv4 FIB tables when possible, to speed
up route lookups even further. From Alexander Duyck.
9) Many improvements and bug fixes to the rhashtable implementation,
from Herbert Xu and Thomas Graf. In particular, in the case where
an rhashtable user bulk adds a large number of items into an empty
table, we expand the table much more sanely.
10) Don't make the tcp_metrics hash table per-namespace, from Eric
Biederman.
11) Extend EBPF to access SKB fields, from Alexei Starovoitov.
12) Split out new connection request sockets so that they can be
established in the main hash table. Much less false sharing since
hash lookups go direct to the request sockets instead of having to
go first to the listener then to the request socks hashed
underneath. From Eric Dumazet.
13) Add async I/O support for crytpo AF_ALG sockets, from Tadeusz Struk.
14) Support stable privacy address generation for RFC7217 in IPV6. From
Hannes Frederic Sowa.
15) Hash network namespace into IP frag IDs, also from Hannes Frederic
Sowa.
16) Convert PTP get/set methods to use 64-bit time, from Richard
Cochran.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1816 commits)
fm10k: Bump driver version to 0.15.2
fm10k: corrected VF multicast update
fm10k: mbx_update_max_size does not drop all oversized messages
fm10k: reset head instead of calling update_max_size
fm10k: renamed mbx_tx_dropped to mbx_tx_oversized
fm10k: update xcast mode before synchronizing multicast addresses
fm10k: start service timer on probe
fm10k: fix function header comment
fm10k: comment next_vf_mbx flow
fm10k: don't handle mailbox events in iov_event path and always process mailbox
fm10k: use separate workqueue for fm10k driver
fm10k: Set PF queues to unlimited bandwidth during virtualization
fm10k: expose tx_timeout_count as an ethtool stat
fm10k: only increment tx_timeout_count in Tx hang path
fm10k: remove extraneous "Reset interface" message
fm10k: separate PF only stats so that VF does not display them
fm10k: use hw->mac.max_queues for stats
fm10k: only show actual queues, not the maximum in hardware
fm10k: allow creation of VLAN on default vid
fm10k: fix unused warnings
...
Pull s390 updates from Martin Schwidefsky:
"The major change in this merge is the removal of the support for
31-bit kernels. Naturally 31-bit user space will continue to work via
the compat layer.
And then some cleanup, some improvements and bug fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (23 commits)
s390/smp: wait until secondaries are active & online
s390/hibernate: fix save and restore of kernel text section
s390/cacheinfo: add missing facility check
s390/syscalls: simplify syscall_get_arch()
s390/irq: enforce correct irqclass_sub_desc array size
s390: remove "64" suffix from mem64.S and swsusp_asm64.S
s390/ipl: cleanup macro usage
s390/ipl: cleanup shutdown_action attributes
s390/ipl: cleanup bin attr usage
s390/uprobes: fix address space annotation
s390: add missing arch_release_task_struct() declaration
s390: make couple of functions and variables static
s390/maccess: improve s390_kernel_write()
s390/maccess: remove potentially broken probe_kernel_write()
s390/watchdog: support for KVM hypervisors and delete pr_info messages
s390/watchdog: enable KEEPALIVE for /dev/watchdog
s390/dasd: remove setting of scheduler from driver
s390/traps: panic() instead of die() on translation exception
s390: remove test_facility(2) (== z/Architecture mode active) checks
s390/cmpxchg: simplify cmpxchg_double
...
Pull timer updates from Ingo Molnar:
"The main changes in this cycle were:
- clockevents state machine cleanups and enhancements (Viresh Kumar)
- clockevents broadcast notifier horror to state machine conversion
and related cleanups (Thomas Gleixner, Rafael J Wysocki)
- clocksource and timekeeping core updates (John Stultz)
- clocksource driver updates and fixes (Ben Dooks, Dmitry Osipenko,
Hans de Goede, Laurent Pinchart, Maxime Ripard, Xunlei Pang)
- y2038 fixes (Xunlei Pang, John Stultz)
- NMI-safe ktime_get_raw_fast() and general refactoring of the clock
code, in preparation to perf's per event clock ID support (Peter
Zijlstra)
- generic sched/clock fixes, optimizations and cleanups (Daniel
Thompson)
- clockevents cpu_down() race fix (Preeti U Murthy)"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (94 commits)
timers/PM: Drop unnecessary braces from tick_freeze()
timers/PM: Fix up tick_unfreeze()
timekeeping: Get rid of stale comment
clockevents: Cleanup dead cpu explicitely
clockevents: Make tick handover explicit
clockevents: Remove broadcast oneshot control leftovers
sched/idle: Use explicit broadcast oneshot control function
ARM: Tegra: Use explicit broadcast oneshot control function
ARM: OMAP: Use explicit broadcast oneshot control function
intel_idle: Use explicit broadcast oneshot control function
ACPI/idle: Use explicit broadcast control function
ACPI/PAD: Use explicit broadcast oneshot control function
x86/amd/idle, clockevents: Use explicit broadcast oneshot control functions
clockevents: Provide explicit broadcast oneshot control functions
clockevents: Remove the broadcast control leftovers
ARM: OMAP: Use explicit broadcast control function
intel_idle: Use explicit broadcast control function
cpuidle: Use explicit broadcast control function
ACPI/processor: Use explicit broadcast control function
ACPI/PAD: Use explicit broadcast control function
...
ARM/ARM64: fixes for live migration, irqfd and ioeventfd support (enabling
vhost, too), page aging
s390: interrupt handling rework, allowing to inject all local interrupts
via new ioctl and to get/set the full local irq state for migration
and introspection. New ioctls to access memory by virtual address,
and to get/set the guest storage keys. SIMD support.
MIPS: FPU and MIPS SIMD Architecture (MSA) support. Includes some patches
from Ralf Baechle's MIPS tree.
x86: bugfixes (notably for pvclock, the others are small) and cleanups.
Another small latency improvement for the TSC deadline timer.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"First batch of KVM changes for 4.1
The most interesting bit here is irqfd/ioeventfd support for ARM and
ARM64.
Summary:
ARM/ARM64:
fixes for live migration, irqfd and ioeventfd support (enabling
vhost, too), page aging
s390:
interrupt handling rework, allowing to inject all local interrupts
via new ioctl and to get/set the full local irq state for migration
and introspection. New ioctls to access memory by virtual address,
and to get/set the guest storage keys. SIMD support.
MIPS:
FPU and MIPS SIMD Architecture (MSA) support. Includes some
patches from Ralf Baechle's MIPS tree.
x86:
bugfixes (notably for pvclock, the others are small) and cleanups.
Another small latency improvement for the TSC deadline timer"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (146 commits)
KVM: use slowpath for cross page cached accesses
kvm: mmu: lazy collapse small sptes into large sptes
KVM: x86: Clear CR2 on VCPU reset
KVM: x86: DR0-DR3 are not clear on reset
KVM: x86: BSP in MSR_IA32_APICBASE is writable
KVM: x86: simplify kvm_apic_map
KVM: x86: avoid logical_map when it is invalid
KVM: x86: fix mixed APIC mode broadcast
KVM: x86: use MDA for interrupt matching
kvm/ppc/mpic: drop unused IRQ_testbit
KVM: nVMX: remove unnecessary double caching of MAXPHYADDR
KVM: nVMX: checks for address bits beyond MAXPHYADDR on VM-entry
KVM: x86: cache maxphyaddr CPUID leaf in struct kvm_vcpu
KVM: vmx: pass error code with internal error #2
x86: vdso: fix pvclock races with task migration
KVM: remove kvm_read_hva and kvm_read_hva_atomic
KVM: x86: optimize delivery of TSC deadline timer interrupt
KVM: x86: extract blocking logic from __vcpu_run
kvm: x86: fix x86 eflags fixed bit
KVM: s390: migrate vcpu interrupt state
...
This is the s390 version of 875ebe940d ("powerpc/smp: Wait until secondaries
are active & online").
The race described in length within the commit message is also possible on s390
and every other architecture. So fix this race on s390 as well.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Sebastian reported a crash caused by a jump label mismatch after resume.
This happens because we do not save the kernel text section during suspend
and therefore also do not restore it during resume, but use the kernel image
that restores the old system.
This means that after a suspend/resume cycle we lost all modifications done
to the kernel text section.
The reason for this is the pfn_is_nosave() function, which incorrectly
returns that read-only pages don't need to be saved. This is incorrect since
we mark the kernel text section read-only.
We still need to make sure to not save and restore pages contained within
NSS and DCSS segment.
To fix this add an extra case for the kernel text section and only save
those pages if they are not contained within an NSS segment.
Fixes the following crash (and the above bugs as well):
Jump label code mismatch at netif_receive_skb_internal+0x28/0xd0
Found: c0 04 00 00 00 00
Expected: c0 f4 00 00 00 11
New: c0 04 00 00 00 00
Kernel panic - not syncing: Corrupted kernel text
CPU: 0 PID: 9 Comm: migration/0 Not tainted 3.19.0-01975-gb1b096e70f23 #4
Call Trace:
[<0000000000113972>] show_stack+0x72/0xf0
[<000000000081f15e>] dump_stack+0x6e/0x90
[<000000000081c4e8>] panic+0x108/0x2b0
[<000000000081be64>] jump_label_bug.isra.2+0x104/0x108
[<0000000000112176>] __jump_label_transform+0x9e/0xd0
[<00000000001121e6>] __sm_arch_jump_label_transform+0x3e/0x50
[<00000000001d1136>] multi_cpu_stop+0x12e/0x170
[<00000000001d1472>] cpu_stopper_thread+0xb2/0x168
[<000000000015d2ac>] smpboot_thread_fn+0x134/0x1b0
[<0000000000158baa>] kthread+0x10a/0x110
[<0000000000824a86>] kernel_thread_starter+0x6/0xc
Reported-and-tested-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Git commit d97d929f06 ("s390: move cacheinfo sysfs to generic cacheinfo
infrastructure") removed the general-instructions-extension availability
check before the ecag instruction is executed.
Without this check this may lead to crashes on machines without this facility.
Therefore add the check again where needed.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
As execution domain support is gone we can remove
signal translation from the signal code and remove
exec_domain from thread_info.
Signed-off-by: Richard Weinberger <richard@nod.at>
Conflicts:
drivers/net/usb/asix_common.c
drivers/net/usb/sr9800.c
drivers/net/usb/usbnet.c
include/linux/usb/usbnet.h
net/ipv4/tcp_ipv4.c
net/ipv6/tcp_ipv6.c
The TCP conflicts were overlapping changes. In 'net' we added a
READ_ONCE() to the socket cached RX route read, whilst in 'net-next'
Eric Dumazet touched the surrounding code dealing with how mini
sockets are handled.
With USB, it's a case of the same bug fix first going into net-next
and then I cherry picked it back into net.
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation of adding another tkr field, rename this one to
tkr_mono. Also rename tk_read_base::base_mono to tk_read_base::base,
since the structure is not specific to CLOCK_MONOTONIC and the mono
name got added to the tk_read_base instance.
Lots of trivial churn.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20150319093400.344679419@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add a BUILD_BUG_ON() to enforce that irqclass_sub_desc contains the required
number of defined interrupt descriptions and won't be filled up with zeros.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Rename two more files which I forgot. Also remove the "asm" from the
swsusp_asm64.S file, since the ".S" suffix already makes it obvious
that this file contains assembler code.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
ipl.c uses 3 different macros to create a sysfs show function for ipl
attributes. Define IPL_ATTR_SHOW_FN which is used by all macros.
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use macros wherever applicable and create a shutdown_action attribute
group to simplify the code.
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use macros wherever applicable and put bin_attributes inside attribute_groups
to simplify/remove some code.
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove __user address space annotation for sim_stor_event() calls since it
generates false positive warnings from sparse.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
As reported by sparse these can and should be static.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the s390 architecture implementation of probe_kernel_write() and
instead use a new function s390_kernel_write() to modify kernel text and
data everywhere.
The s390 implementation of probe_kernel_write() was potentially broken
since it modified memory in a read-modify-write fashion, which read four
bytes, modified the requested bytes within those four bytes and wrote
the result back.
If two cpus would modify the same four byte area at different locations
within that area, this could lead to corruption.
Right now the only places which called probe_kernel_write() did run within
stop_machine_run. Therefore the scenario can't happen right now, however
that might change at any time.
To fix this rename probe_kernel_write() to s390_kernel_write() which can
have special semantics, like only call it while running within stop_machine().
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In case of a translation exception the page tables are corrupted. If the
exception handler then calls die() which again calls show_regs()
-> show_code() -> copy_from_user(), the kernel may access the same memory
location again and generates yet another translation exception. Which in turn
will lead to a deadlock on the die_lock spinlock, which the kernel tries to
grab recursively.
Given that the page tables are corrupted anyway, if we see such an exception,
let's simply panic.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the 31 bit syscalls from the syscall table. This is a separate patch
just in case I screwed something up so it can be easily reverted.
However the conversion was done with a script, so everything should be ok.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Rename a couple of files to get rid of the "64" suffix.
"git blame" will still work.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.
The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e58 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.
Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
After a suspend/resume cycle we missed to enable smt again, which leads
to all sorts of bugs, since the kernel assumes smt is enabled, while the
hardware thinks it is not.
Reported-and-tested-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reported-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The SF_CYCLES_BASIC_DIAG is always registered even if it is turned of in the
current hardware configuration. Because diagnostic-sampling is typically not
turned on in the hardware configuration, do not register this perf event by
default. Enable it only if the diagnostic-sampling function is authorized.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A long running project has been to clean up remaining uses
of clocksource_register(), replacing it with the simpler
clocksource_register_khz/hz() functions.
However, there are a few cases where we need to self-define
our mult/shift values, so switch the function to a more
obviously internal __clocksource_register() name, and
consolidate much of the internal logic so we don't have
duplication.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: David S. Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1426133800-29329-10-git-send-email-john.stultz@linaro.org
[ Minor cleanups. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1. Several Fixes and enhancements
---------------------------------
- These 3 patches have cc stable:
b75f4c9 KVM: s390: Zero out current VMDB of STSI before including level3 data.
261520d KVM: s390: fix handling of write errors in the tpi handler
15462e3 KVM: s390: reinjection of irqs can fail in the tpi handler
2. SIMD support the kernel part (introduced with z13)
-----------------------------------------------------
- two KVM-generic changes in kvm.h:
1. New capability that can be enabled: KVM_CAP_S390_VECTOR_REGISTERS
2. increased padding size for sync regs in struct kvm_run to clarify that
sync regs can be larger than 1k. This is fine as this is the last
element in the structure.
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Merge tag 'kvm-s390-next-20150306' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into queue
KVM: s390: Features and Fixes for 4.1 (kvm/next)
1. Several Fixes and enhancements
---------------------------------
- These 3 patches have cc stable:
b75f4c9 KVM: s390: Zero out current VMDB of STSI before including level3 data.
261520d KVM: s390: fix handling of write errors in the tpi handler
15462e3 KVM: s390: reinjection of irqs can fail in the tpi handler
2. SIMD support the kernel part (introduced with z13)
-----------------------------------------------------
- two KVM-generic changes in kvm.h:
1. New capability that can be enabled: KVM_CAP_S390_VECTOR_REGISTERS
2. increased padding size for sync regs in struct kvm_run to clarify that
sync regs can be larger than 1k. This is fine as this is the last
element in the structure.
Conflicts:
drivers/net/ethernet/cadence/macb.c
Overlapping changes in macb driver, mostly fixes and cleanups
in 'net' overlapping with the integration of at91_ether into
macb in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Store additional status in the machine check handler, in order to
collect status (such as vector registers) that is not defined by
store status.
Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Conflicts:
drivers/net/ethernet/rocker/rocker.c
The rocker commit was two overlapping changes, one to rename
the ->vport member to ->pport, and another making the bitmask
expression use '1ULL' instead of plain '1'.
Signed-off-by: David S. Miller <davem@davemloft.net>
With git commit 4d92f50249 ("s390: reintroduce diag 44 calls for
cpu_relax()") I reintroduced a non-trivial cpu_relax() variant on s390.
The difference to the previous variant however is that the new version is
an out-of-line function, which will be traced if function tracing is enabled.
Switching to different tracers includes instruction patching. Therefore this
is done within stop_machine() "context" to prevent that any function tracing
is going on while instructions are being patched.
With the new out-of-line variant of cpu_relax() this is not true anymore,
since cpu_relax() gets called in a busy loop by all waiting cpus within
stop_machine() until function patching is finished.
Therefore cpu_relax() must be marked notrace.
This fixes kernel crashes when frequently switching between "function" and
"function_graph" tracers.
Moving cpu_relax() to a header file again, doesn't work because of header
include order dependencies.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
claw devices are outdated and no longer supported.
This patch removes the claw driver.
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the output of the jump label sanity check and also print the
code pattern that is supposed to be written to the jump label.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 fixes from Martin Schwidefsky:
"Two patches to save some memory if CONFIG_NR_CPUS is large, a changed
default for the use of compare-and-delay, and a couple of bug fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/spinlock: disabled compare-and-delay by default
s390/mm: align 64-bit PIE binaries to 4GB
s390/cacheinfo: coding style changes
s390/cacheinfo: fix shared cpu masks
s390/smp: reduce size of struct pcpu
s390/topology: convert cpu_topology array to per cpu variable
s390/topology: delay initialization of topology cpu masks
s390/vdso: fix clock_gettime for CLOCK_THREAD_CPUTIME_ID, -2 and -3
Until we have hard performance data about the effects of CAD in the
spinlock loop disable the instruction by default.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
For instrumenting global variables KASan will shadow memory backing memory
for modules. So on module loading we will need to allocate memory for
shadow and map it at address in shadow that corresponds to the address
allocated in module_alloc().
__vmalloc_node_range() could be used for this purpose, except it puts a
guard hole after allocated area. Guard hole in shadow memory should be a
problem because at some future point we might need to have a shadow memory
at address occupied by guard hole. So we could fail to allocate shadow
for module_alloc().
Now we have VM_NO_GUARD flag disabling guard page, so we need to pass into
__vmalloc_node_range(). Add new parameter 'vm_flags' to
__vmalloc_node_range() function.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Common: Optional support for adding a small amount of polling on each HLT
instruction executed in the guest (or equivalent for other architectures).
This can improve latency up to 50% on some scenarios (e.g. O_DSYNC writes
or TCP_RR netperf tests). This also has to be enabled manually for now,
but the plan is to auto-tune this in the future.
ARM/ARM64: the highlights are support for GICv3 emulation and dirty page
tracking
s390: several optimizations and bugfixes. Also a first: a feature
exposed by KVM (UUID and long guest name in /proc/sysinfo) before
it is available in IBM's hypervisor! :)
MIPS: Bugfixes.
x86: Support for PML (page modification logging, a new feature in
Broadwell Xeons that speeds up dirty page tracking), nested virtualization
improvements (nested APICv---a nice optimization), usual round of emulation
fixes. There is also a new option to reduce latency of the TSC deadline
timer in the guest; this needs to be tuned manually.
Some commits are common between this pull and Catalin's; I see you
have already included his tree.
ARM has other conflicts where functions are added in the same place
by 3.19-rc and 3.20 patches. These are not large though, and entirely
within KVM.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM update from Paolo Bonzini:
"Fairly small update, but there are some interesting new features.
Common:
Optional support for adding a small amount of polling on each HLT
instruction executed in the guest (or equivalent for other
architectures). This can improve latency up to 50% on some
scenarios (e.g. O_DSYNC writes or TCP_RR netperf tests). This
also has to be enabled manually for now, but the plan is to
auto-tune this in the future.
ARM/ARM64:
The highlights are support for GICv3 emulation and dirty page
tracking
s390:
Several optimizations and bugfixes. Also a first: a feature
exposed by KVM (UUID and long guest name in /proc/sysinfo) before
it is available in IBM's hypervisor! :)
MIPS:
Bugfixes.
x86:
Support for PML (page modification logging, a new feature in
Broadwell Xeons that speeds up dirty page tracking), nested
virtualization improvements (nested APICv---a nice optimization),
usual round of emulation fixes.
There is also a new option to reduce latency of the TSC deadline
timer in the guest; this needs to be tuned manually.
Some commits are common between this pull and Catalin's; I see you
have already included his tree.
Powerpc:
Nothing yet.
The KVM/PPC changes will come in through the PPC maintainers,
because I haven't received them yet and I might end up being
offline for some part of next week"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (130 commits)
KVM: ia64: drop kvm.h from installed user headers
KVM: x86: fix build with !CONFIG_SMP
KVM: x86: emulate: correct page fault error code for NoWrite instructions
KVM: Disable compat ioctl for s390
KVM: s390: add cpu model support
KVM: s390: use facilities and cpu_id per KVM
KVM: s390/CPACF: Choose crypto control block format
s390/kernel: Update /proc/sysinfo file with Extended Name and UUID
KVM: s390: reenable LPP facility
KVM: s390: floating irqs: fix user triggerable endless loop
kvm: add halt_poll_ns module parameter
kvm: remove KVM_MMIO_SIZE
KVM: MIPS: Don't leak FPU/DSP to guest
KVM: MIPS: Disable HTW while in guest
KVM: nVMX: Enable nested posted interrupt processing
KVM: nVMX: Enable nested virtual interrupt delivery
KVM: nVMX: Enable nested apic register virtualization
KVM: nVMX: Make nested control MSRs per-cpu
KVM: nVMX: Enable nested virtualize x2apic mode
KVM: nVMX: Prepare for using hardware MSR bitmap
...
If an attacker can cause a controlled kernel stack overflow, overwriting
the restart block is a very juicy exploit target. This is because the
restart_block is held in the same memory allocation as the kernel stack.
Moving the restart block to struct task_struct prevents this exploit by
making the restart_block harder to locate.
Note that there are other fields in thread_info that are also easy
targets, at least on some architectures.
It's also a decent simplification, since the restart code is more or less
identical on all architectures.
[james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Richard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Just some minor coding style changes, while I had to look at the code.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When testing Sudeep Holla's cache info rework I didn't realize that the
shared cpu masks are broken (all have the same cpu set).
Let's fix this.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reduce the size of struct pcpu, since the pcpu_devices array consists
of NR_CPUS elements of type struct pcpu. For most machines this is just
a waste of memory.
So let's try to make it a bit smaller.
This saves 16k with performance_defconfig.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Convert the per cpu topology cpu masks to a per cpu variable.
At least for machines which do have less possible cpus than NR_CPUS this can
save a bit of memory (z/VM: max 64 vs 512 for performance_defconfig).
This reduces the kernel image size by 100k.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There is no reason to initialize the topology cpu masks already while
setup_arch() is being called. It is sufficient to initialize the masks
before the scheduler becomes SMP aware.
Therefore a pre-SMP initcall aka early_initcall is suffucient.
This also allows to convert the cpu_topology array into a per cpu
variable with a later patch. Without this patch this wouldn't be
possible since the per cpu memory areas are not allocated while setup_arch
is executed.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Git commit 8d8f2e18a6dbd3d09dd918788422e6ac8c878e96
"s390/vdso: ectg gettime support for CLOCK_THREAD_CPUTIME_ID"
broke clock_gettime for CLOCK_THREAD_CPUTIME_ID.
Git commit c742b31c03
"fast vdso implementation for CLOCK_THREAD_CPUTIME_ID"
introduced the ECTG for clock id -2. Correct would have been
clock id -3.
Fix the whole mess, CLOCK_THREAD_CPUTIME_ID is based on
CPUCLOCK_SCHED and can not be speed up by the vdso. A speedup
is only available for clock id -3 which is CPUCLOCK_VIRT for
the task currently running on the CPU.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 updates from Martin Schwidefsky:
- The remaining patches for the z13 machine support: kernel build
option for z13, the cache synonym avoidance, SMT support,
compare-and-delay for spinloops and the CES5S crypto adapater.
- The ftrace support for function tracing with the gcc hotpatch option.
This touches common code Makefiles, Steven is ok with the changes.
- The hypfs file system gets an extension to access diagnose 0x0c data
in user space for performance analysis for Linux running under z/VM.
- The iucv hvc console gets wildcard spport for the user id filtering.
- The cacheinfo code is converted to use the generic infrastructure.
- Cleanup and bug fixes.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (42 commits)
s390/process: free vx save area when releasing tasks
s390/hypfs: Eliminate hypfs interval
s390/hypfs: Add diagnose 0c support
s390/cacheinfo: don't use smp_processor_id() in preemptible context
s390/zcrypt: fixed domain scanning problem (again)
s390/smp: increase maximum value of NR_CPUS to 512
s390/jump label: use different nop instruction
s390/jump label: add sanity checks
s390/mm: correct missing space when reporting user process faults
s390/dasd: cleanup profiling
s390/dasd: add locking for global_profile access
s390/ftrace: hotpatch support for function tracing
ftrace: let notrace function attribute disable hotpatching if necessary
ftrace: allow architectures to specify ftrace compile options
s390: reintroduce diag 44 calls for cpu_relax()
s390/zcrypt: Add support for new crypto express (CEX5S) adapter.
s390/zcrypt: Number of supported ap domains is not retrievable.
s390/spinlock: add compare-and-delay to lock wait loops
s390/tape: remove redundant if statement
s390/hvc_iucv: add simple wildcard matches to the iucv allow filter
...
If a task uses vector registers, a save area is allocated to save/restore
register states. Free the save area when releasing the task.
Found the Memory leak with kmemleak:
unreferenced object 0x72885e00 (size 512):
comm "vx-test", pid 26123, jiffies 4294945635 (age 256.810s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 01 db 71 06 41 .............q.A
00 00 00 00 00 00 00 00 24 f7 a9 a7 51 94 79 bb ........$...Q.y.
backtrace:
[<00000000002d1c8a>] kmem_cache_alloc_trace+0x272/0x3d0
[<00000000001014ac>] alloc_vector_registers+0x54/0x138
[<00000000001017c8>] data_exception+0x158/0x1b0
[<00000000008b551e>] pgm_check_handler+0x13e/0x180
[<00000000800008b6>] 0x800008b6
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
show_cacheinfo() needs to access the cacheinfo structure of any online
cpu. This was done with using smp_processor_id() as in index while in
preemtible context.
This means the cpu could be offline and the data be gone when it would
be accessed.
Better use any online cpu address and protect the data by get_online_cpus()
and put_online_cpus().
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A new architecture extends STSI 3.2.2 with UUID and long names. KVM
will provide the first implementation. This patch adds the additional
data fields (Extended Name and UUID) from the 4KB block returned by
the STSI 3.2.2 command and reflect this information in the
/proc/sysinfo file accordingly.
Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Use a brcl 0,2 instruction for jump label nops during compile time,
so we don't mix up the different nops during mcount/hotpatch call
site detection.
The initial jump label code instruction replacement will exchange
these instructions with either a branch or a brcl 0,0 instruction.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add sanity checks to verify that only expected code will be replaced.
If the code patterns do not match print the code patterns and panic,
since something went terribly wrong.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make use of gcc's hotpatch support to generate better code for ftrace
function tracing.
The generated code now contains only a six byte nop in each function
prologue instead of a 24 byte code block which will be runtime patched to
support function tracing.
With the new code generation the runtime overhead for supporting function
tracing is close to zero, while the original code did show a significant
performance impact.
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Christian Borntraeger reported that the now missing diag 44 calls (voluntary
time slice end) does cause a performance regression for stop_machine() calls
if a machine has more virtual cpus than the host has physical cpus.
This patch mainly reverts 57f2ffe14f ("s390: remove diag 44 calls from
cpu_relax()") with the exception that we still do not issue diag 44 calls if
running with smt enabled. Due to group scheduling algorithms when running in
LPAR this would lead to significant latencies.
However, when running in LPAR we do not have more virtual than physical cpus.
Reported-and-tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add the compare-and-delay instruction to the spin-lock and rw-lock
retry loops. A CPU executing the compare-and-delay instruction stops
until the lock value has changed. This is done to make the locking
code for contended locks to behave better in regard to the multi-
hreading facility. A thread of a core executing a compare-and-delay
will allow the other threads of a core to get a larger share of the
core resources.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
First two are minor fallout from the param rework which went in this merge
window.
Next three are a series which fixes a longstanding (but never previously
reported and unlikely , so no CC stable) race between kallsyms and freeing
the init section.
Finally, a minor cleanup as our module refcount will now be -1 during
unload.
Thanks,
Rusty.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module and param fixes from Rusty Russell:
"Surprising number of fixes this merge window :(
The first two are minor fallout from the param rework which went in
this merge window.
The next three are a series which fixes a longstanding (but never
previously reported and unlikely , so no CC stable) race between
kallsyms and freeing the init section.
Finally, a minor cleanup as our module refcount will now be -1 during
unload"
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
module: make module_refcount() a signed integer.
module: fix race in kallsyms resolution during module load success.
module: remove mod arg from module_free, rename module_memfree().
module_arch_freeing_init(): new hook for archs before module->module_init freed.
param: fix uninitialized read with CONFIG_DEBUG_LOCK_ALLOC
param: initialize store function to NULL if not available.
Commit 725908110a1f ("s390: add SMT support") added a check for
CONFIG_ZFCPDUMP. But the Kconfig symbol ZFCPDUMP was removed in v3.16
through commit bf28a5970d ("s390/dump: Remove CONFIG_ZFCPDUMP"). So
this check will always evaluate to false. No one noticed probably
because the code also checks for CONFIG_CRASH_DUMP which "also enables
s390 zfcpdump".
Dump the unneeded check.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The multi-threading facility is introduced with the z13 processor family.
This patch adds code to detect the multi-threading facility. With the
facility enabled each core will surface multiple hardware threads to the
system. Each hardware threads looks like a normal CPU to the operating
system with all its registers and properties.
The SCLP interface reports the SMT topology indirectly via the maximum
thread id. Each reported CPU in the result of a read-scp-information
is a core representing a number of hardware threads.
To reflect the reduced CPU capacity if two hardware threads run on a
single core the MT utilization counter set is used to normalize the
raw cputime obtained by the CPU timer deltas. This scaled cputime is
reported via the taskstats interface. The normal /proc/stat numbers
are based on the raw cputime and are not affected by the normalization.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Avoid cache aliasing on z13 by aligning shared objects to multiples
of 512K. The virtual addresses of a page from a shared file needs
to have identical bits in the range 2^12 to 2^18.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Archs have been abusing module_free() to clean up their arch-specific
allocations. Since module_free() is also (ab)used by BPF and trace code,
let's keep it to simple allocations, and provide a hook called before
that.
This means that avr32, ia64, parisc and s390 no longer need to implement
their own module_free() at all. avr32 doesn't need module_finalize()
either.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org
If uprobes are single stepped for example with gdb, the behavior should
now be correct. Before this patch, when gdb was single stepping a uprobe,
the result was a SIGILL.
When PER is active for any storage alteration and a uprobe is hit, a storage
alteration event is indicated. These over indications are filterd out by gdb,
if no change has happened within the observed area.
Signed-off-by: Jan Willeke <willeke@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch removes the redundant sysfs cacheinfo code by reusing
the newly introduced generic cacheinfo infrastructure through the
commit 246246cbde ("drivers: base: support cpu cache information
interface to userspace via sysfs")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
_sclp_print_early() has a return value, but misses to sign extend it
if called from 64 bit code.
This is not really a bug, since currently no caller cares what the
return value is.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of sparse warnings like this one:
arch/s390/kernel/signal.c:244:1:
warning: symbol 'sys_sigreturn' was not declared. Should it be static?
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Always verify that the to be replaced code matches what we expect to see.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
in the cpu time accounting function vtime_account_irq_enter
(vtime_account_system) we use a WARN_ON_ONCE(!irqs_disabled()).
This is redundant as the function virt_timer_forward is always
called and has a BUG_ON(!irqs_disabled()).
This saves several nanoseconds in my specific testcase (KVM entry/exit)
and probably all other callers like (soft)irq entry/exit.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull user namespace related fixes from Eric Biederman:
"As these are bug fixes almost all of thes changes are marked for
backporting to stable.
The first change (implicitly adding MNT_NODEV on remount) addresses a
regression that was created when security issues with unprivileged
remount were closed. I go on to update the remount test to make it
easy to detect if this issue reoccurs.
Then there are a handful of mount and umount related fixes.
Then half of the changes deal with the a recently discovered design
bug in the permission checks of gid_map. Unix since the beginning has
allowed setting group permissions on files to less than the user and
other permissions (aka ---rwx---rwx). As the unix permission checks
stop as soon as a group matches, and setgroups allows setting groups
that can not later be dropped, results in a situtation where it is
possible to legitimately use a group to assign fewer privileges to a
process. Which means dropping a group can increase a processes
privileges.
The fix I have adopted is that gid_map is now no longer writable
without privilege unless the new file /proc/self/setgroups has been
set to permanently disable setgroups.
The bulk of user namespace using applications even the applications
using applications using user namespaces without privilege remain
unaffected by this change. Unfortunately this ix breaks a couple user
space applications, that were relying on the problematic behavior (one
of which was tools/selftests/mount/unprivileged-remount-test.c).
To hopefully prevent needing a regression fix on top of my security
fix I rounded folks who work with the container implementations mostly
like to be affected and encouraged them to test the changes.
> So far nothing broke on my libvirt-lxc test bed. :-)
> Tested with openSUSE 13.2 and libvirt 1.2.9.
> Tested-by: Richard Weinberger <richard@nod.at>
> Tested on Fedora20 with libvirt 1.2.11, works fine.
> Tested-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
> Ok, thanks - yes, unprivileged lxc is working fine with your kernels.
> Just to be sure I was testing the right thing I also tested using
> my unprivileged nsexec testcases, and they failed on setgroup/setgid
> as now expected, and succeeded there without your patches.
> Tested-by: Serge Hallyn <serge.hallyn@ubuntu.com>
> I tested this with Sandstorm. It breaks as is and it works if I add
> the setgroups thing.
> Tested-by: Andy Lutomirski <luto@amacapital.net> # breaks things as designed :("
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
userns: Unbreak the unprivileged remount tests
userns; Correct the comment in map_write
userns: Allow setting gid_maps without privilege when setgroups is disabled
userns: Add a knob to disable setgroups on a per user namespace basis
userns: Rename id_map_mutex to userns_state_mutex
userns: Only allow the creator of the userns unprivileged mappings
userns: Check euid no fsuid when establishing an unprivileged uid mapping
userns: Don't allow unprivileged creation of gid mappings
userns: Don't allow setgroups until a gid mapping has been setablished
userns: Document what the invariant required for safe unprivileged mappings.
groups: Consolidate the setgroups permission checks
mnt: Clear mnt_expire during pivot_root
mnt: Carefully set CL_UNPRIVILEGED in clone_mnt
mnt: Move the clear of MNT_LOCKED from copy_tree to it's callers.
umount: Do not allow unmounting rootfs.
umount: Disallow unprivileged mount force
mnt: Update unprivileged remount test
mnt: Implicitly add MNT_NODEV on remount when it was implicitly added by mount
Pull s390 updates from Martin Schwidefsky:
"The most notable change for this pull request is the ftrace rework
from Heiko. It brings a small performance improvement and the ground
work to support a new gcc option to replace the mcount blocks with a
single nop.
Two new s390 specific system calls are added to emulate user space
mmio for PCI, an artifact of the how PCI memory is accessed.
Two patches for the memory management with changes to common code.
For KVM mm_forbids_zeropage is added which disables the empty zero
page for an mm that is used by a KVM process. And an optimization,
pmdp_get_and_clear_full is added analog to ptep_get_and_clear_full.
Some micro optimization for the cmpxchg and the spinlock code.
And as usual bug fixes and cleanups"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (46 commits)
s390/cputime: fix 31-bit compile
s390/scm_block: make the number of reqs per HW req configurable
s390/scm_block: handle multiple requests in one HW request
s390/scm_block: allocate aidaw pages only when necessary
s390/scm_block: use mempool to manage aidaw requests
s390/eadm: change timeout value
s390/mm: fix memory leak of ptlock in pmd_free_tlb
s390: use local symbol names in entry[64].S
s390/ptrace: always include vector registers in core files
s390/simd: clear vector register pointer on fork/clone
s390: translate cputime magic constants to macros
s390/idle: convert open coded idle time seqcount
s390/idle: add missing irq off lockdep annotation
s390/debug: avoid function call for debug_sprintf_*
s390/kprobes: fix instruction copy for out of line execution
s390: remove diag 44 calls from cpu_relax()
s390/dasd: retry partition detection
s390/dasd: fix list corruption for sleep_on requests
s390/dasd: fix infinite term I/O loop
s390/dasd: remove unused code
...
To improve the output of the perf tool hide most of the symbols
from entry[64].S by using the '.L' prefix.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
On machines with support for vector registers the signal frame includes
an area for the vector registers and the ptrace regset interface allow
read and write. This is true even if the task never used any vector
instruction. Only elf core dumps do not include the vector registers,
to make things consistent always include the vector register note in
core dumps create on a machine with vector register support.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The copy_thread function fails to reset the p->thread.vxrs pointer.
This causes the child to use the same vector register save area,
causing both data corruptions and multiple frees of the memory for
the save area after the tasks sharing the save area terminate.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
s390 uses open coded seqcount to synchronize idle time accounting.
Lets consolidate it with the standard API.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
psw_idle() returns with interrupts disabled, so we should add the
missing annotation.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
debug_sprintf_event/exception are called even for debug events
with a disabling debug level. All other functions already do
the check in a wrapper function. Lets do the same here.
Due to the var_args the compiler rejects to make this function
inline. So let's wrap this via a macro.
This patch saves around 80 ns on my z196 for a KVM round trip (we
have two debug statements for entry and exit) when KVM is build as
a module.
The savings for built-in drivers is smaller as we then avoid the
PLT overhead for a function call.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Today there are 3 instances of setgroups and due to an oversight their
permission checking has diverged. Add a common function so that
they may all share the same permission checking code.
This corrects the current oversight in the current permission checks
and adds a helper to avoid this in the future.
A user namespace security fix will update this new helper, shortly.
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
When we generate the instruction for out of line execution the length
of the to be copied instruction was evaluated from a not initialized
memory location.
Therefore we ended up with a random (2, 4 or 6) number of bytes being
copied instead of taking the real instruction length into account.
This works surprisingly well most of the time, but still not always.
Reported-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit eb7e7d76 "s390: Replace __get_cpu_var uses" broke machine check
handling.
We copy machine check information from per-cpu to a stack variable for
local processing. Next we should zap the per-cpu variable, not the
stack variable.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Translation exceptions should never happen, since that implies that
either we screwed up the page tables or missed to properly flush the TLB.
In both cases we should not just simply kill user space or walk the kernel
exception tables. Instead an oops or a panic (panic_on_oops) is the better
answer.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
It always confuses me to see the mixed instruction length code and
interruption code on user space faults, while the message clearly
says it is the interruption code.
So split the value and print both values separately. Also add the ILC
output to the die() message, so thar user and kernel space faults
contain the same information.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add the new __NR_s390_pci_mmio_write and __NR_s390_pci_mmio_read
system calls to allow user space applications to access device PCI I/O
memory pages on s390x platform.
[ Martin Schwidefsky: some code beautification ]
Signed-off-by: Alexey Ishchuk <aishchuk@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The floating point registers of a process that uses vector instruction are
not store into task->thread.fp_regs anymore but in the upper halves of the
first 16 vector registers.
The ptrace interface for the peeks and pokes to the user area fails to take
this into account. Fix __peek_user[_compat] and __poke_user[_compat]
to use the vector array for the floating pointer register if the process
has one.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Irq 0 is currently unused on s390. Since there is no reason to
do this start counting at the beginning and gain an additional
irq. Also correctly report the smallest usable irq number for
dynamic allocation.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 update from Martin Schwidefsky:
"One small improvement for the cputime accounting, two bug fixes and an
update for the default configuration files"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/ftrace: add ftrace_graph_is_dead() check
s390: update default configuration
s390/vdso: fix stack corruption
s390/time: use stck clock fast for do_account_vtime
The git commit c719f56092
"perf: Fix and clean up initialization of pmu::event_idx" removed
the PMU event index callback for all architectures but x86,
remove the initialization of the event index as well.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix the following warnings from the sparse code checker:
arch/s390/kernel/signal.c:374:38: warning: cast removes address space of expression
arch/s390/kernel/signal.c:374:65: warning: incorrect type in initializer (different address spaces)
arch/s390/kernel/signal.c:374:65: expected unsigned short [noderef] [usertype] <asn:1>*svc
arch/s390/kernel/signal.c:374:65: got void *
arch/s390/kernel/compat_signal.c:437:38: warning: cast removes address space of expression
arch/s390/kernel/compat_signal.c:437:65: warning: incorrect type in initializer (different address spaces)
arch/s390/kernel/compat_signal.c:437:65: expected unsigned short [noderef] [usertype] <asn:1>*svc
arch/s390/kernel/compat_signal.c:437:65: got void *
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The kernel build for s390 fails for gcc compilers with version 3.x,
set the minimum required version of gcc to version 4.3.
As the atomic builtins are available with all gcc 4.x compilers,
use the __sync_val_compare_and_swap and __sync_bool_compare_and_swap
functions to replace the complex macro and inline assembler magic
in include/asm/cmpxchg.h. The compiler can just-do-it and generates
better code with the builtins.
While we are at it use __sync_bool_compare_and_swap for the
_raw_compare_and_swap function in the spinlock code as well.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, plus on the kernel side:
- a revert for a newly introduced PMU driver which isn't complete yet
and where we ran out of time with fixes (to be tried again in
v3.19) - this makes up for a large chunk of the diffstat.
- compilation warning fixes
- a printk message fix
- event_idx usage fixes/cleanups"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf probe: Trivial typo fix for --demangle
perf tools: Fix report -F dso_from for data without branch info
perf tools: Fix report -F dso_to for data without branch info
perf tools: Fix report -F symbol_from for data without branch info
perf tools: Fix report -F symbol_to for data without branch info
perf tools: Fix report -F mispredict for data without branch info
perf tools: Fix report -F in_tx for data without branch info
perf tools: Fix report -F abort for data without branch info
perf tools: Make CPUINFO_PROC an array to support different kernel versions
perf callchain: Use global caching provided by libunwind
perf/x86/intel: Revert incomplete and undocumented Broadwell client support
perf/x86: Fix compile warnings for intel_uncore
perf: Fix typos in sample code in the perf_event.h header
perf: Fix and clean up initialization of pmu::event_idx
perf: Fix bogus kernel printk
perf diff: Add missing hists__init() call at tool start
Andy reported that the current state of event_idx is rather confused.
So remove all but the x86_pmu implementation and change the default to
return 0 (the safe option).
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: Cody P Schafer <dev@codyps.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Himangi Saraogi <himangi774@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: sukadev@linux.vnet.ibm.com <sukadev@linux.vnet.ibm.com>
Cc: Thomas Huth <thuth@linux.vnet.ibm.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux390@de.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add an ftrace_graph_is_dead() check to prepare_ftrace_return() in order to
detect an internal ftrace graph error. This allows to prevent further ftrace
graph handling and hopefully keeps the kernel alive.
This patch is the same like for all other architectures.
For unkown reasons s390 was left out.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use NOKPROBE_SYMBOL() instead of __kprobes annotation.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the function tracer is enabled, allow to set kprobes on the first
instruction of a function (which is the function trace caller):
If no kprobe is set handling of enabling and disabling function tracing
of a function simply patches the first instruction. Either it is a nop
(right now it's an unconditional branch, which skips the mcount block),
or it's a branch to the ftrace_caller() function.
If a kprobe is being placed on a function tracer calling instruction
we encode if we actually have a nop or branch in the remaining bytes
after the breakpoint instruction (illegal opcode).
This is possible, since the size of the instruction used for the nop
and branch is six bytes, while the size of the breakpoint is only
two bytes.
Therefore the first two bytes contain the illegal opcode and the last
four bytes contain either "0" for nop or "1" for branch. The kprobes
code will then execute/simulate the correct instruction.
Instruction patching for kprobes and function tracer is always done
with stop_machine(). Therefore we don't have any races where an
instruction is patched concurrently on a different cpu.
Besides that also the program check handler which executes the function
trace caller instruction won't be executed concurrently to any
stop_machine() execution.
This allows to keep full fault based kprobes handling which generates
correct pt_regs contents automatically.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Martin Schwidefsky