Patch "perf/x86/intel: Don't accidentally clear high bits in bdw_limit_period()" has been added to the 4.9-stable tree

Patch "perf/x86/intel: Don't accidentally clear high bits in bdw_limit_period()" has been added to the 4.9-stable tree

[gregkh]

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@vger.kernel.org> know about it.


>From e5ea9b54a055619160bbfe527ebb7d7191823d66 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
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@oracle.com>

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 |    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@oracle.com 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