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authorIngo Molnar <mingo@elte.hu>2009-05-17 11:08:41 +0200
committerIngo Molnar <mingo@elte.hu>2009-05-29 14:28:37 +0200
commit012b84dae17126d8b5d159173091eb3db5a2bc43 (patch)
tree0b5f85b66084c3186a8e4c56d9ed074d3b2593ee /kernel
parent3f4dee227348daac32f36daad9a91059efd0723e (diff)
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perf_counter: Robustify counter-free logic
This fixes a nasty crash and highlights a bug that we were freeing failed-fork() counters incorrectly. (the fix for that will come separately) [ Impact: fix crashes/lockups with inherited counters ] Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/perf_counter.c4
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index eb346048f00f..616c52426b32 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -1004,6 +1004,10 @@ static void __perf_counter_task_sched_out(struct perf_counter_context *ctx)
if (!cpuctx->task_ctx)
return;
+
+ if (WARN_ON_ONCE(ctx != cpuctx->task_ctx))
+ return;
+
__perf_counter_sched_out(ctx, cpuctx);
cpuctx->task_ctx = NULL;
}