diff options
| author | Dan Carpenter <dan.carpenter@oracle.com> | 2018-03-17 14:52:16 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-28 18:40:16 +0200 |
| commit | 95cdf6bdceddcbefeba6a15b488d816aab4ac203 (patch) | |
| tree | c95c3edf4e2e541ca9dbbf3f34305dcec7f063f9 /arch/x86 | |
| parent | c6fe55e30bb6d431ee56cd4bbb582e30766c5e0e (diff) | |
perf/x86/intel: Don't accidentally clear high bits in bdw_limit_period()
commit e5ea9b54a055619160bbfe527ebb7d7191823d66 upstream.
We intended to clear the lowest 6 bits but because of a type bug we
clear the high 32 bits as well. Andi says that periods are rarely more
than U32_MAX so this bug probably doesn't have a huge runtime impact.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 294fe0f52a44 ("perf/x86/intel: Add INST_RETIRED.ALL workarounds")
Link: http://lkml.kernel.org/r/20180317115216.GB4035@mwanda
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index 5cc2242d77c6..7b79c80ce029 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -2716,7 +2716,7 @@ static unsigned bdw_limit_period(struct perf_event *event, unsigned left) X86_CONFIG(.event=0xc0, .umask=0x01)) { if (left < 128) left = 128; - left &= ~0x3fu; + left &= ~0x3fULL; } return left; } |