Files
linux/kernel
Peter Zijlstra b32df66680 perf/core: Fix perf_sample_regs_user() mm check
[ Upstream commit 085ebfe937 ]

perf_sample_regs_user() uses 'current->mm' to test for the presence of
userspace, but this is insufficient, consider use_mm().

A better test is: '!(current->flags & PF_KTHREAD)', exec() clears
PF_KTHREAD after it sets the new ->mm but before it drops to userspace
for the first time.

Possibly obsoletes: bf05fc25f2 ("powerpc/perf: Fix oops when kthread execs user process")

Reported-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Reported-by: Young Xiao <92siuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
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: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 4018994f3d ("perf: Add ability to attach user level registers dump to sample")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-21 09:06:05 +02:00
..
2019-05-16 19:43:40 +02:00
2017-09-02 07:07:53 +02:00
2016-01-22 18:04:28 -05:00
2016-04-04 09:46:47 -04:00
2019-05-31 06:48:20 -07:00
2015-04-12 21:03:31 +02:00
2019-01-13 10:03:51 +01:00
2015-11-23 09:44:58 +01:00
2018-08-03 07:55:12 +02:00
2016-02-16 13:04:58 -05:00
2017-05-20 14:28:40 +02:00
2015-01-17 10:02:23 +13:00
2016-03-01 20:36:56 +01:00
2018-08-03 07:55:24 +02:00
2018-05-09 09:50:20 +02:00
2016-09-22 20:00:36 -05:00