From f6f5a30c834135c9f2fa10400c59ebbdd9188567 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 6 Mar 2012 17:34:50 +0100 Subject: ARM: 7356/1: perf: check that we have an event in the PMU IRQ handlers The PMU IRQ handlers in perf assume that if a counter has overflowed then perf must be responsible. In the paranoid world of crazy hardware, this could be false, so check that we do have a valid event before attempting to dereference NULL in the interrupt path. Cc: Signed-off-by: Ming Lei Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/perf_event_v7.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/arm/kernel/perf_event_v7.c') diff --git a/arch/arm/kernel/perf_event_v7.c b/arch/arm/kernel/perf_event_v7.c index 050cc8bf7246..4d7095af2ab3 100644 --- a/arch/arm/kernel/perf_event_v7.c +++ b/arch/arm/kernel/perf_event_v7.c @@ -960,6 +960,10 @@ static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev) struct perf_event *event = cpuc->events[idx]; struct hw_perf_event *hwc; + /* Ignore if we don't have an event. */ + if (!event) + continue; + /* * We have a single interrupt for all counters. Check that * each counter has overflowed before we process it. -- cgit v1.2.2