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[tip:perf/core] perf/x86: Fix undefined shift on 32-bit kernels

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Commit-ID:  6d6f2833bfbf296101f9f085e10488aef2601ba5
Gitweb:     http://git.kernel.org/tip/6d6f2833bfbf296101f9f085e10488aef2601ba5
Author:     Andrey Ryabinin <aryabinin@virtuozzo.com>
AuthorDate: Wed, 11 May 2016 16:51:51 +0300
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Thu, 12 May 2016 10:14:31 +0200

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

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@gmail.com>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.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: Imre Palik <imrep@amazon.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@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@kernel.org>
---
 arch/x86/events/intel/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index a6fd4db..5210eaa 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -3708,7 +3708,7 @@ __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);
 		}
 	}

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[PATCH] perf/x86: fix undefined shift on 32-bit kernels Andrey Ryabinin <aryabinin@virtuozzo.com> - 2016-05-11 16:10 +0200
  Re: [PATCH] perf/x86: fix undefined shift on 32-bit kernels Peter Zijlstra <peterz@infradead.org> - 2016-05-11 16:10 +0200
  [tip:perf/core] perf/x86: Fix undefined shift on 32-bit kernels tip-bot for Andrey Ryabinin <tipbot@zytor.com> - 2016-05-12 12:40 +0200

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