Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932378Ab1BPAim (ORCPT ); Tue, 15 Feb 2011 19:38:42 -0500 Received: from kroah.org ([198.145.64.141]:49539 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932202Ab1BPAXy (ORCPT ); Tue, 15 Feb 2011 19:23:54 -0500 X-Mailbox-Line: From gregkh@clark.kroah.org Tue Feb 15 16:14:45 2011 Message-Id: <20110216001445.654656926@clark.kroah.org> User-Agent: quilt/0.48-11.2 Date: Tue, 15 Feb 2011 16:14:22 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Oleg Nesterov , Peter Zijlstra , Alan Stern , Arnaldo Carvalho de Melo , Frederic Weisbecker , Paul Mackerras , Prasad , Roland McGrath , Ingo Molnar Subject: [205/272] perf: Find_get_context: fix the per-cpu-counter check In-Reply-To: <20110216001559.GA31413@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1628 Lines: 50 2.6.37-stable review patch. If anyone has any objections, please let us know. ------------------ From: Oleg Nesterov 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 Acked-by: Peter Zijlstra Cc: Alan Stern Cc: Arnaldo Carvalho de Melo Cc: Frederic Weisbecker Cc: Paul Mackerras Cc: Prasad Cc: Roland McGrath LKML-Reference: <20110118161008.GB693@redhat.com> Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- kernel/perf_event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -2100,7 +2100,7 @@ find_get_context(struct pmu *pmu, struct 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); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/