perf: Find_get_context: fix the per-cpu-counter check
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>
Cc: gregkh@suse.de
Cc: stable@kernel.org
LKML-Reference: <20110118161008.GB693@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
parent
c5ed514559
commit
22a4ec7290
|
@ -2228,7 +2228,7 @@ 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);
|
||||
|
|
Loading…
Reference in New Issue