This is a note to let you know that I've just added the patch titled perf/x86/intel: Don't accidentally clear high bits in bdw_limit_period() to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: perf-x86-intel-don-t-accidentally-clear-high-bits-in-bdw_limit_period.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From e5ea9b54a055619160bbfe527ebb7d7191823d66 Mon Sep 17 00:00:00 2001 From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Date: Sat, 17 Mar 2018 14:52:16 +0300 Subject: perf/x86/intel: Don't accidentally clear high bits in bdw_limit_period() From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> 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@xxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Vince Weaver <vincent.weaver@xxxxxxxxx> 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@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/events/intel/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -3025,7 +3025,7 @@ static unsigned bdw_limit_period(struct X86_CONFIG(.event=0xc0, .umask=0x01)) { if (left < 128) left = 128; - left &= ~0x3fu; + left &= ~0x3fULL; } return left; } Patches currently in stable-queue which might be from dan.carpenter@xxxxxxxxxx are queue-4.9/perf-x86-intel-don-t-accidentally-clear-high-bits-in-bdw_limit_period.patch queue-4.9/staging-ncpfs-memory-corruption-in-ncp_read_kernel.patch