Barret Rhoden ad41c68eb7 perf: Add cond_resched() to task_function_call() ...

commit 2ed6edd33a214bca02bd2b45e3fc3038a059436b upstream.

Under rare circumstances, task_function_call() can repeatedly fail and
cause a soft lockup.

There is a slight race where the process is no longer running on the cpu
we targeted by the time remote_function() runs.  The code will simply
try again.  If we are very unlucky, this will continue to fail, until a
watchdog fires.  This can happen in a heavily loaded, multi-core virtual
machine.

Reported-by: syzbot+bb4935a5c09b5ff79940@syzkaller.appspotmail.com
Signed-off-by: Barret Rhoden <brho@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200414222920.121401-1-brho@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2020-06-20 10:25:06 +02:00

..

callchain.c

perf: Remove superfluous allocation error check

2018-05-16 10:10:24 +02:00

core.c

perf: Add cond_resched() to task_function_call()

2020-06-20 10:25:06 +02:00

hw_breakpoint.c

perf/hwbp: Simplify the perf-hwbp code, fix documentation

2018-04-08 14:26:27 +02:00

internal.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

Makefile

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

ring_buffer.c

perf/ring-buffer: Always use {READ,WRITE}_ONCE() for rb->user_page data

2019-06-22 08:16:16 +02:00

uprobes.c

uprobes: ensure that uprobe->offset and ->ref_ctr_offset are properly aligned

2020-06-11 09:23:01 +02:00