4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Dan Carpenter <[email protected]> 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 <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Sebastian Andrzej Siewior <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Vince Weaver <[email protected]> Fixes: 294fe0f52a44 ("perf/x86/intel: Add INST_RETIRED.ALL workarounds") Link: http://lkml.kernel.org/r/20180317115216.GB4035@mwanda Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/x86/kernel/cpu/perf_event_intel.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- 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 X86_CONFIG(.event=0xc0, .umask=0x01)) { if (left < 128) left = 128; - left &= ~0x3fu; + left &= ~0x3fULL; } return left; }
