From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751996AbdHZHMn (ORCPT ); Sat, 26 Aug 2017 03:12:43 -0400 Received: from mail-wm0-f67.google.com ([74.125.82.67]:34475 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750736AbdHZHMm (ORCPT ); Sat, 26 Aug 2017 03:12:42 -0400 Date: Sat, 26 Aug 2017 09:12:38 +0200 From: Ingo Molnar To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Arnaldo Carvalho de Melo , Alexander Shishkin , Thomas Gleixner , Andrew Morton Subject: [GIT PULL] perf fix Message-ID: <20170826071238.h27pfhtfx23g4fvz@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, Please pull the latest perf-urgent-for-linus git tree from: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus # HEAD: 64aee2a965cf2954a038b5522f11d2cd2f0f8f3e perf/core: Fix group {cpu,task} validation A single fix to not allow nonsensical event groups that result in kernel warnings. Thanks, Ingo ------------------> Mark Rutland (1): perf/core: Fix group {cpu,task} validation kernel/events/core.c | 39 +++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 20 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index ee20d4c546b5..3504125871d2 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -10032,28 +10032,27 @@ SYSCALL_DEFINE5(perf_event_open, goto err_context; /* - * Do not allow to attach to a group in a different - * task or CPU context: + * Make sure we're both events for the same CPU; + * grouping events for different CPUs is broken; since + * you can never concurrently schedule them anyhow. */ - if (move_group) { - /* - * Make sure we're both on the same task, or both - * per-cpu events. - */ - if (group_leader->ctx->task != ctx->task) - goto err_context; + if (group_leader->cpu != event->cpu) + goto err_context; - /* - * Make sure we're both events for the same CPU; - * grouping events for different CPUs is broken; since - * you can never concurrently schedule them anyhow. - */ - if (group_leader->cpu != event->cpu) - goto err_context; - } else { - if (group_leader->ctx != ctx) - goto err_context; - } + /* + * Make sure we're both on the same task, or both + * per-CPU events. + */ + if (group_leader->ctx->task != ctx->task) + goto err_context; + + /* + * Do not allow to attach to a group in a different task + * or CPU context. If we're moving SW events, we'll fix + * this up later, so allow that. + */ + if (!move_group && group_leader->ctx != ctx) + goto err_context; /* * Only a group leader can be exclusive or pinned