[4.2.y-ckt stable] Patch "perf/x86: Fix undefined shift on 32-bit kernels" has been added to the 4.2.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    perf/x86: Fix undefined shift on 32-bit kernels

to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree 
which can be found at:

    https://git.launchpad.net/~canonical-kernel/linux/+git/linux-stable-ckt/log/?h=linux-4.2.y-queue

This patch is scheduled to be released in version 4.2.8-ckt11.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 4.2.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From 65a24865e9289c4b5e4cfd6683bcbacb340f9a10 Mon Sep 17 00:00:00 2001
From: Andrey Ryabinin <aryabinin at virtuozzo.com>
Date: Wed, 11 May 2016 16:51:51 +0300
Subject: perf/x86: Fix undefined shift on 32-bit kernels

commit 6d6f2833bfbf296101f9f085e10488aef2601ba5 upstream.

Jim reported:

	UBSAN: Undefined behaviour in arch/x86/events/intel/core.c:3708:12
	shift exponent 35 is too large for 32-bit type 'long unsigned int'

The use of 'unsigned long' type obviously is not correct here, make it
'unsigned long long' instead.

Reported-by: Jim Cromie <jim.cromie at gmail.com>
Signed-off-by: Andrey Ryabinin <aryabinin at virtuozzo.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz at infradead.org>
Cc: Alexander Shishkin <alexander.shishkin at linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme at redhat.com>
Cc: H. Peter Anvin <hpa at zytor.com>
Cc: Imre Palik <imrep at amazon.de>
Cc: Jiri Olsa <jolsa at redhat.com>
Cc: Linus Torvalds <torvalds at linux-foundation.org>
Cc: Peter Zijlstra <peterz at infradead.org>
Cc: Stephane Eranian <eranian at google.com>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: Vince Weaver <vincent.weaver at maine.edu>
Fixes: 2c33645d366d ("perf/x86: Honor the architectural performance monitoring version")
Link: http://lkml.kernel.org/r/1462974711-10037-1-git-send-email-aryabinin@virtuozzo.com
Signed-off-by: Ingo Molnar <mingo at kernel.org>
[ kamal: backport to 4.2-stable: file moved ]
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 arch/x86/kernel/cpu/perf_event_intel.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index 5bbcddf..ed7fe82 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -3328,7 +3328,7 @@ __init int intel_pmu_init(void)
 				c->idxmsk64 |= (1ULL << x86_pmu.num_counters) - 1;
 			}
 			c->idxmsk64 &=
-				~(~0UL << (INTEL_PMC_IDX_FIXED + x86_pmu.num_counters_fixed));
+				~(~0ULL << (INTEL_PMC_IDX_FIXED + x86_pmu.num_counters_fixed));
 			c->weight = hweight64(c->idxmsk64);
 		}
 	}
--
2.7.4