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Subject[PATCH] perf_events: fix validate_event bug
Date
	The validate_event() was failing on valid event
combinations. The function was assuming that if
x86_schedule_event() returned 0, it meant error.
But x86_schedule_event() returns the counter index
and 0 is a perfectly valid value. An error is returned
if the function returns a negative value.

Furthermore, validate_event() was also failing for
event groups because the event->pmu was not set until
after hw_perf_pmu_init().

Signed-off-by: Stephane Eranian <eranian@gmail.com>
--
arch/x86/kernel/cpu/perf_event.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 2e20bca..d321ff7 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -2229,10 +2229,7 @@ validate_event(struct cpu_hw_events *cpuc, struct perf_event *event)
{
struct hw_perf_event fake_event = event->hw;

- if (event->pmu != &pmu)
- return 0;
-
- return x86_schedule_event(cpuc, &fake_event);
+ return x86_schedule_event(cpuc, &fake_event) >= 0;
}

static int validate_group(struct perf_event *event)

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