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Commit ad5013d5 authored by Colin King's avatar Colin King Committed by Thomas Gleixner
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perf/x86/intel: Use ULL constant to prevent undefined shift behaviour 



When x86_pmu.num_counters is 32 the shift of the integer constant 1 is
exceeding 32bit and therefor undefined behaviour.

Fix this by shifting 1ULL instead of 1.

Reported-by: CoverityScan CID#1192105 ("Bad bit shift operation")
Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: http://lkml.kernel.org/r/20170111114310.17928-1-colin.king@canonical.com


Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 6d6daa20

arch/x86/events/intel/core.c

+1 −1
Original line number Diff line number Diff line
@@ -3987,7 +3987,7 @@ __init int intel_pmu_init(void) 
		     x86_pmu.num_counters, INTEL_PMC_MAX_GENERIC);

		x86_pmu.num_counters = INTEL_PMC_MAX_GENERIC;

	}

	x86_pmu.intel_ctrl = (1 << x86_pmu.num_counters) - 1;

	x86_pmu.intel_ctrl = (1ULL << x86_pmu.num_counters) - 1;



	if (x86_pmu.num_counters_fixed > INTEL_PMC_MAX_FIXED) {

		WARN(1, KERN_ERR "hw perf events fixed %d > max(%d), clipping!",