diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2011-01-18 17:10:08 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-02-17 15:14:47 -0800 |
| commit | ccb6b70738a85a74512d1b74539d22d61120acbf (patch) | |
| tree | 18f0705ab76125a63149272c49b1b2f3be7142e8 /kernel | |
| parent | 785fb57c98233ad3d9818259c3c139585cfbff3e (diff) | |
perf: Find_get_context: fix the per-cpu-counter check
commit 22a4ec729017ba613337a28f306f94ba5023fe2e upstream.
If task == NULL, find_get_context() should always check that cpu
is correct.
Afaics, the bug was introduced by 38a81da2 "perf events: Clean
up pid passing", but even before that commit "&& cpu != -1" was
not exactly right, -ESRCH from find_task_by_vpid() is not
accurate.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
LKML-Reference: <20110118161008.GB693@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/perf_event.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 8465baf40087..31ce59108c9d 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -2100,7 +2100,7 @@ find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) unsigned long flags; int ctxn, err; - if (!task && cpu != -1) { + if (!task) { /* Must be root to operate on a CPU event: */ if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) return ERR_PTR(-EACCES); |