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perf/x86/intel: Don't accidentally clear high bits in bdw_limit_period()
authorDan Carpenter <dan.carpenter@oracle.com>
Sat, 17 Mar 2018 11:52:16 +0000 (14:52 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 28 Mar 2018 16:39:25 +0000 (18:39 +0200)
commite91ec3494168e1d4505f413effe0dfbbbcc64208
tree12d93c22a900792e42747a5fc65ccc8eed3ab7cf
parenta8b3a6a4ae5e7b790cdc62335a6f5952c3f9b6ea
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>
arch/x86/events/intel/core.c