perf/trace: Properly use u64 to hold event_id

The 64-bit attr.config value for perf trace events was being copied into
an "int" before doing a comparison, meaning the top 32 bits were
being truncated.

As far as I can tell this didn't cause any errors, but it did mean
it was possible to create valid aliases for all the tracepoint ids
which I don't think was intended.  (For example, 0xffffffff00000018
and 0x18 both enable the same tracepoint).

Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1311151236100.11932@vincent-weaver-1.um.maine.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 630889f68b1d34808049694405850476f5c7a4d9..e854f420e033eb65a2bca233bb8df2e42778faf7 100644 (file)
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -179,7 +179,7 @@ static int perf_trace_event_init(struct ftrace_event_call *tp_event,
 int perf_trace_init(struct perf_event *p_event)
 {
        struct ftrace_event_call *tp_event;
-       int event_id = p_event->attr.config;
+       u64 event_id = p_event->attr.config;
        int ret = -EINVAL;
 
        mutex_lock(&event_mutex);