This patch updates the PEBS support for Intel Atom to provide
an alias for the cycles:pp event used by perf record/top by default
nowadays.
On Atom, only INST_RETIRED:ANY supports PEBS, so we use this event
instead with a large cmask to count cycles. Given that Core2 has
the same issue, we use the intel_pebs_aliases_core2() function for Atom
as well.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Link: http://lkml.kernel.org/r/1449172990-30183-3-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes broken PEBS support on Intel Atom and Core2
due to wrong pointer arithmetic in intel_pmu_drain_pebs_core().
The get_next_pebs_record_by_bit() was called on PEBS format fmt0
which does not use the pebs_record_nhm layout.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Fixes: 21509084f9 ("perf/x86/intel: Handle multiple records in the PEBS buffer")
Link: http://lkml.kernel.org/r/1449182000-31524-3-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patches fixes the LBR kernel crashes on Intel Atom.
The kernel was assuming that if the CPU supports 64-bit format
LBR, then it has an LBR_SELECT MSR. Atom uses 64-bit LBR format
but does not have LBR_SELECT. That was causing NULL pointer
dereferences in a couple of places.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Fixes: 96f3eda67f ("perf/x86/intel: Fix static checker warning in lbr enable")
Link: http://lkml.kernel.org/r/1449182000-31524-2-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes a bug in the filter_events() function.
The patch fixes the bug whereby if some mappings did not
exist, e.g., STALLED_CYCLES_FRONTEND, then any event after it
in the attrs array would disappear from the published list of
events in /sys/devices/cpu/events. This could be verified
easily on any system post SNB (which do not publish
STALLED_CYCLES_FRONTEND):
$ ./perf stat -e cycles,ref-cycles true
Performance counter stats for 'true':
1,217,348 cycles
<not supported> ref-cycles
The problem is that in filter_events() there is an assumption
that the argument (attrs) is organized in increasing continuous
event indexes related to the event_map(). But if we remove the
non-supported events by shifing the position in the array, then
the lookup x86_pmu.event_map() needs to compensate for it, otherwise
we are looking up the wrong index. This patch corrects this problem
by compensating for the deleted events and with that ref-cycles
reappears (here shown on Haswell):
$ perf stat -e ref-cycles,cycles true
Performance counter stats for 'true':
4,525,910 ref-cycles
1,064,920 cycles
0.002943888 seconds time elapsed
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: jolsa@kernel.org
Cc: kan.liang@intel.com
Fixes: 8300daa267 ("perf/x86: Filter out undefined events from sysfs events attribute")
Link: http://lkml.kernel.org/r/1449516805-6637-1-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add a new 'three-p' precise level, that uses INST_RETIRED.PREC_DIST as
base. The basic mechanism of abusing the inverse cmask to get all
cycles works the same as before.
PREC_DIST is available on Sandy Bridge or later. It had some problems
on Sandy Bridge, so we only use it on IvyBridge and later. I tested it
on Broadwell and Skylake.
PREC_DIST has special support for avoiding shadow effects, which can
give better results compare to UOPS_RETIRED. The drawback is that
PREC_DIST can only schedule on counter 1, but that is ok for cycle
sampling, as there is normally no need to do multiple cycle sampling
runs in parallel. It is still possible to run perf top in parallel, as
that doesn't use precise mode. Also of course the multiplexing can
still allow parallel operation.
:pp stays with the previous event.
Example:
Sample a loop with 10 sqrt with old cycles:pp
0.14 │10: sqrtps %xmm1,%xmm0 <--------------
9.13 │ sqrtps %xmm1,%xmm0
11.58 │ sqrtps %xmm1,%xmm0
11.51 │ sqrtps %xmm1,%xmm0
6.27 │ sqrtps %xmm1,%xmm0
10.38 │ sqrtps %xmm1,%xmm0
12.20 │ sqrtps %xmm1,%xmm0
12.74 │ sqrtps %xmm1,%xmm0
5.40 │ sqrtps %xmm1,%xmm0
10.14 │ sqrtps %xmm1,%xmm0
10.51 │ ↑ jmp 10
We expect all 10 sqrt to get roughly the sample number of samples.
But you can see that the instruction directly after the JMP is
systematically underestimated in the result, due to sampling shadow
effects.
With the new PREC_DIST based sampling this problem is gone and all
instructions show up roughly evenly:
9.51 │10: sqrtps %xmm1,%xmm0
11.74 │ sqrtps %xmm1,%xmm0
11.84 │ sqrtps %xmm1,%xmm0
6.05 │ sqrtps %xmm1,%xmm0
10.46 │ sqrtps %xmm1,%xmm0
12.25 │ sqrtps %xmm1,%xmm0
12.18 │ sqrtps %xmm1,%xmm0
5.26 │ sqrtps %xmm1,%xmm0
10.13 │ sqrtps %xmm1,%xmm0
10.43 │ sqrtps %xmm1,%xmm0
0.16 │ ↑ jmp 10
Even with PREC_DIST there is still sampling skid and the result is not
completely even, but systematic shadow effects are significantly
reduced.
The improvements are mainly expected to make a difference in high IPC
code. With low IPC it should be similar.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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>
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1448929689-13771-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
I added UOPS_RETIRED.ALL by mistake to the Skylake PEBS event list for
cycles:pp. But the event is not documented for Skylake, and has some
issues.
The recommended replacement for cycles:pp is to use
INST_RETIRED.ANY+pebs as a base, similar to what CPUs before Sandy
Bridge did. This new event is called INST_RETIRED.TOTAL_CYCLES_PS. The
event is not really new, but has been already used by perf before
Sandy Bridge for the original cycles:p
Note the SDM doesn't document that event either, but it's being
documented in the latest version of the event list on:
https://download.01.org/perfmon/SKL
This patch does:
- Remove UOPS_RETIRED.ALL from the Skylake PEBS event list
- Add INST_RETIRED.ANY to the Skylake PEBS event list, and an table entry to
allow cmask=16,inv=1 for cycles:pp
- We don't need an extra entry for the base INST_RETIRED event,
because it is already covered by the catch-all PEBS table entry.
- Switch Skylake to use the Core2 PEBS alias (which is
INST_RETIRED.TOTAL_CYCLES_PS)
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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>
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1448929689-13771-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Normally we drop PEBS events with a zero status field. But when
there is only a single PEBS event active we can assume the
PEBS record is for that event. The PEBS buffer is always flushed
when PEBS events are disabled, so there is no risk of mishandling
state PEBS records this way.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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/1449177740-5422-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The recent commit:
75f80859b1 ("perf/x86/intel/pebs: Robustify PEBS buffer drain")
causes lots of warnings on different CPUs before Skylake
when running PEBS intensive workloads.
They can have a zero status field in the PEBS record when
PEBS is racing with clearing of GLOBAl_STATUS.
This also can cause hangs (it seems there are still
problems with printk in NMI).
Disable the warning, but still ignore the record.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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/1449177740-5422-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch collapses the two 'hard' cases, which are
perf_event_{dis,en}able().
I cannot seem to convince myself the current code is correct.
So starting with perf_event_disable(); we don't strictly need to test
for event->state == ACTIVE, ctx->is_active is enough. If the event is
not scheduled while the ctx is, __perf_event_disable() still does the
right thing. Its a little less efficient to IPI in that case,
over-all simpler.
For perf_event_enable(); the same goes, but I think that's actually
broken in its current form. The current condition is: ctx->is_active
&& event->state == OFF, that means it doesn't do anything when
!ctx->active && event->state == OFF. This is wrong, it should still
mark the event INACTIVE in that case, otherwise we'll still not try
and schedule the event once the context becomes active again.
This patch implements the two function using the new
event_function_call() and does away with the tricky event->state
tests.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Alexander Shishkin <alexander.shishkin@intel.com>
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>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If a newly created task is selected to go to a different CPU in fork
balance when it wakes up the first time, its load averages should
not be removed from the source CPU since they are never added to
it before. The same is also applicable to a never used group entity.
Fix it in remove_entity_load_avg(): when entity's last_update_time
is 0, simply return. This should precisely identify the case in
question, because in other migrations, the last_update_time is set
to 0 after remove_entity_load_avg().
Reported-by: Steve Muckle <steve.muckle@linaro.org>
Signed-off-by: Yuyang Du <yuyang.du@intel.com>
[peterz: cfs_rq_last_update_time]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <Juri.Lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Patrick Bellasi <patrick.bellasi@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: http://lkml.kernel.org/r/20151216233427.GJ28098@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The sched_entity::avg collides with read-mostly sched_entity data.
The perf c2c tool showed many read HITM accesses across
many CPUs for sched_entity's cfs_rq and my_q, while having
at the same time tons of stores for avg.
After placing sched_entity::avg into separate cache line,
the perf bench sched pipe showed around 20 seconds speedup.
NOTE I cut out all perf events except for cycles and
instructions from following output.
Before:
$ perf stat -r 5 perf bench sched pipe -l 10000000
# Running 'sched/pipe' benchmark:
# Executed 10000000 pipe operations between two processes
Total time: 270.348 [sec]
27.034805 usecs/op
36989 ops/sec
...
245,537,074,035 cycles # 1.433 GHz
187,264,548,519 instructions # 0.77 insns per cycle
272.653840535 seconds time elapsed ( +- 1.31% )
After:
$ perf stat -r 5 perf bench sched pipe -l 10000000
# Running 'sched/pipe' benchmark:
# Executed 10000000 pipe operations between two processes
Total time: 251.076 [sec]
25.107678 usecs/op
39828 ops/sec
...
244,573,513,928 cycles # 1.572 GHz
187,409,641,157 instructions # 0.76 insns per cycle
251.679315188 seconds time elapsed ( +- 0.31% )
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1449606239-28602-1-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The CHECK_MEMBER_AT_END_OF(TYPE, MEMBER) checks whether MEMBER
is last member of TYPE by evaluating:
offsetof(TYPE::MEMBER) + sizeof(TYPE::MEMBER) == sizeof(TYPE)
and ensuring TYPE::MEMBER is the last member of the TYPE.
This condition breaks on structs that are padded to be
aligned. This patch ensures the TYPE alignment is taken
into account.
This bug was revealed after adding cacheline alignment into
struct sched_entity, which broke task_struct::thread check:
CHECK_MEMBER_AT_END_OF(struct task_struct, thread);
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1450707930-3445-1-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
earliest_dl.next should cache deadline of the earliest ready task that
is also enqueued in the pushable rbtree, as pull algorithm uses this
information to find candidates for migration: if the earliest_dl.next
deadline of source rq is earlier than the earliest_dl.curr deadline of
destination rq, the task from the source rq can be pulled.
However, current implementation only guarantees that earliest_dl.next is
the deadline of the next ready task instead of the next pushable task;
which will result in potentially holding both rqs' lock and find nothing
to migrate because of affinity constraints. In addition, current logic
doesn't update the next candidate for pushing in pick_next_task_dl(),
even if the running task is never eligible.
This patch fixes both problems by updating earliest_dl.next when
pushable dl task is enqueued/dequeued, similar to what we already do for
RT.
Tested-by: Luca Abeni <luca.abeni@unitn.it>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1449135730-27202-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In the following commit:
7675104990 ("sched: Implement lockless wake-queues")
we gained lockless wake-queues.
The -RT kernel managed to lockup itself with those. There could be multiple
attempts for task X to enqueue it for a wakeup _even_ if task X is already
running.
The reason is that task X could be runnable but not yet on CPU. The the
task performing the wakeup did not leave the CPU it could performe
multiple wakeups.
With the proper timming task X could be running and enqueued for a
wakeup. If this happens while X is performing a fork() then its its
child will have a !NULL `wake_q` member copied.
This is not a problem as long as the child task does not participate in
lockless wakeups :)
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 7675104990 ("sched: Implement lockless wake-queues")
Link: http://lkml.kernel.org/r/20151221171710.GA5499@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some of the sched bitfieds (notably sched_reset_on_fork) can be set
on other than current, this can cause the r-m-w to race with other
updates.
Since all the sched bits are serialized by scheduler locks, pull them
in a separate word.
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: hannes@cmpxchg.org
Cc: mhocko@kernel.org
Cc: vdavydov@parallels.com
Link: http://lkml.kernel.org/r/20151125150207.GM11639@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Our global init task can have sub-threads, so ->pid check is not reliable
enough for is_global_init(), we need to check tgid instead. This has been
spotted by Oleg and a fix was proposed by Richard a long time ago (see the
link below).
Oleg wrote:
: Because is_global_init() is only true for the main thread of /sbin/init.
:
: Just look at oom_unkillable_task(). It tries to not kill init. But, say,
: select_bad_process() can happily find a sub-thread of is_global_init()
: and still kill it.
I recently hit the problem in question; re-sending the patch (to the
best of my knowledge it has never been submitted) with updated function
comment. Credit goes to Oleg and Richard.
Suggested-by: Richard Guy Briggs <rgb@redhat.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W . Biederman <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge E . Hallyn <serge.hallyn@ubuntu.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://www.redhat.com/archives/linux-audit/2013-December/msg00086.html
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Make 'r' 64-bit type to avoid overflow in 'r * LOAD_AVG_MAX'
on 32-bit systems:
UBSAN: Undefined behaviour in kernel/sched/fair.c:2785:18
signed integer overflow:
87950 * 47742 cannot be represented in type 'int'
The most likely effect of this bug are bad load average numbers
resulting in weird scheduling. It's also likely that this can
persist for a longer time - until the system goes idle for
a long time so that all load avg numbers get reset.
[ This is the CFS load average metric, not the procfs output, which
is separate. ]
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 9d89c257df ("sched/fair: Rewrite runnable load and utilization average tracking")
Link: http://lkml.kernel.org/r/1450097243-30137-1-git-send-email-aryabinin@virtuozzo.com
[ Improved the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There's a race on CPU unplug where we free the swevent hash array
while it can still have events on. This will result in a
use-after-free which is BAD.
Simply do not free the hash array on unplug. This leaves the thing
around and no use-after-free takes place.
When the last swevent dies, we do a for_each_possible_cpu() iteration
anyway to clean these up, at which time we'll free it, so no leakage
will occur.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.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>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/built-in.o: In function `arch_setup_additional_pages':
(.text+0x587): undefined reference to `pvclock_pvti_cpu0_va'
KVM_GUEST selects PARAVIRT_CLOCK, so we can make pvclock_pvti_cpu0_va depend
on KVM_GUEST.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Tested-by: Borislav Petkov <bp@alien8.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/444d38a9bcba832685740ea1401b569861d09a72.1451446564.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This reverts commit e958e079e2 ("dmaengine: mic_x100: add missing
spin_unlock").
The above patch is incorrect. There is nothing wrong with the original
code. The spin_lock is acquired in the "prep" functions and released
in "submit".
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
When a qdisc is using per cpu stats (currently just the ingress
qdisc) only the bstats are being freed. This also free's the qstats.
Fixes: b0ab6f9275 ("net: sched: enable per cpu qstats")
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The LSR instruction cannot be used to perform a zero right shift since a
0 as the immediate value (imm5) in the LSR instruction encoding means
that a shift of 32 is perfomed. See DecodeIMMShift() in the ARM ARM.
Make the JIT skip generation of the LSR if a zero-shift is requested.
This was found using american fuzzy lop.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit acf673a318 fixed a user triggerable free
memory scribble but in doing so replaced it with a different one that allows
the user to control the data and scribble even more.
sixpack_close is called by the tty layer in tty context. The tty context is
protected by sp_get() and sp_put(). However network layer activity via
sp_xmit() is not protected this way. We must therefore stop the queue
otherwise the user gets to dump a buffer mostly of their choice into freed
kernel pages.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The SKF_AD_ALU_XOR_X ancillary is not like the other ancillary data
instructions since it XORs A with X while all the others replace A with
some loaded value. All the BPF JITs fail to clear A if this is used as
the first instruction in a filter. This was found using american fuzzy
lop.
Add a helper to determine if A needs to be cleared given the first
instruction in a filter, and use this in the JITs. Except for ARM, the
rest have only been compile-tested.
Fixes: 3480593131 ("net: filter: get rid of BPF_S_* enum")
Signed-off-by: Rabin Vincent <rabin@rab.in>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
stm_is_locked_sr() takes the status register (SR) value as the last
parameter, not the second.
Reported-by: Bayi Cheng <bayi.cheng@mediatek.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Bayi Cheng <bayi.cheng@mediatek.com>
Spansion and Winbond have occasionally used the same manufacturer ID,
and they don't support the same features. Particularly, writing SR=0
seems to break read access for Spansion's s25fl064k. Unfortunately, we
don't currently have a way to differentiate these Spansion and Winbond
parts, so rather than regressing support for these Spansion flash, let's
drop the new Winbond lock/unlock support for now. We can try to address
Winbond support during the next release cycle.
Original discussion:
http://patchwork.ozlabs.org/patch/549173/http://patchwork.ozlabs.org/patch/553683/
Fixes: 357ca38d47 ("mtd: spi-nor: support lock/unlock/is_locked for Winbond")
Fixes: c6fc2171b2 ("mtd: spi-nor: disable protection for Winbond flash at startup")
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reported-by: Felix Fietkau <nbd@openwrt.org>
Cc: Felix Fietkau <nbd@openwrt.org>
[I stole this patch from Eric Biederman. He wrote:]
> There is no defined mechanism to pass network namespace information
> into /sbin/bridge-stp therefore don't even try to invoke it except
> for bridge devices in the initial network namespace.
>
> It is possible for unprivileged users to cause /sbin/bridge-stp to be
> invoked for any network device name which if /sbin/bridge-stp does not
> guard against unreasonable arguments or being invoked twice on the
> same network device could cause problems.
[Hannes: changed patch using netns_eq]
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
1. The recordmcount change had an output that used sprintf() (incorrectly)
when it should have been a fprintf() to stderr.
2. The printk_formats file could crash if someone added a trace_printk()
in the core kernel, and also added one in a module. This does not
affect production kernels. Only kernels where developers add trace_printk()
for debugging can crash.
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Merge tag 'trace-v4.4-rc4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Two more fixes:
1. The recordmcount change had an output that used sprintf()
(incorrectly) when it should have been a fprintf() to stderr.
2. The printk_formats file could crash if someone added a
trace_printk() in the core kernel, and also added one in a module.
This does not affect production kernels. Only kernels where
developers add trace_printk() for debugging can crash"
* tag 'trace-v4.4-rc4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix setting of start_index in find_next()
ftrace/scripts: Fix incorrect use of sprintf in recordmcount
Pull tile bugfix from Chris Metcalf:
"This fixes a bug that Sudip's buildbot found for tilepro allmodconfig.
I've tagged it for stable only back to 3.19, which was when most of
the other affected architectures added their support for working
around this issue"
* 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
tile: provide CONFIG_PAGE_SIZE_64KB etc for tilepro
Unlike the registers file we don't have any substantial performance
concerns rendering the entire file (it involves no device accesses) so
just use seq_printf() to simplify the code.
Signed-off-by: Mark Brown <broonie@kernel.org>
Some of devices supports the trigger level for interrupt
like rising/falling edge specially for GPIOs. The interrupt
support of such devices may have uses the generic regmap irq
framework for implementation.
Add support to configure the trigger type device interrupt
register via regmap-irq framework. The regmap-irq framework
configures the trigger register only if the details of trigger
type registers are provided.
[Fixed use of terery operator for legibility -- broonie]
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use to_platform_device() instead of open-coding it.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The misc control register is 32bit wide, the used readw/writew
accessors only mainipulate the low 16bit of this register. It
currently doesn't matter as all the bit changed are located in
the lower half, but together with the u32 variable used to hold
the contents of the register it is seriously confusing.
Switch to 32bit accessors to avoid any future breakage.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Keep the quirk bits, as Tegra30 and Tegra114 host have different levels
of support for UHS-I modes and so need different spare bits to be set,
but change the logic to be positive.
Tegra210 needs a different tuning sequence than Tegra30+. Disable
UHS modes until support for this is properly added.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This allows the build system to know that it can't attempt to
configure the Lustre virtual block device, for example, when tilepro
is using 64KB pages (as it does by default). The tilegx build
already provided those symbols.
Previously we required that the tilepro hypervisor be rebuilt with
a different hardcoded page size in its headers, and then Linux be
rebuilt using the updated hypervisor header. Now we allow each of
the hypervisor and Linux to be built independently. We still check
at boot time to ensure that the page size provided by the hypervisor
matches what Linux expects.
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Cc: stable@vger.kernel.org [3.19+]
Huang Rui
Stephane Eranian
Andi Kleen
Peter Zijlstra
Ingo Molnar
Yuyang Du
Jiri Olsa
Wanpeng Li
Sebastian Andrzej Siewior
Sergey Senozhatsky
Andrey Ryabinin
Andy Lutomirski
Ashutosh Dixit
John Fastabend
Rabin Vincent
One Thousand Gnomes
Brian Norris
Mark Brown
Hannes Frederic Sowa
Linus Torvalds
Laxman Dewangan
Jaehoon Chung
Geliang Tang
Lucas Stach
Chris Metcalf
John Crispin