From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762366AbZCTK0a (ORCPT ); Fri, 20 Mar 2009 06:26:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761319AbZCTKZ0 (ORCPT ); Fri, 20 Mar 2009 06:25:26 -0400 Received: from hera.kernel.org ([140.211.167.34]:35170 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759328AbZCTKZY (ORCPT ); Fri, 20 Mar 2009 06:25:24 -0400 Date: Fri, 20 Mar 2009 10:24:50 GMT From: Peter Zijlstra To: linux-tip-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, paulus@samba.org, hpa@zytor.com, mingo@redhat.com, rostedt@goodmis.org, a.p.zijlstra@chello.nl, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, paulus@samba.org, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, rostedt@goodmis.org, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <20090319194233.195392657@chello.nl> References: <20090319194233.195392657@chello.nl> Subject: [tip:perfcounters/core] perf_counter: fix uninitialized usage of event_list Message-ID: Git-Commit-ID: 50d8b58c48c7acb4f4ed80c24593ffe2a9c7d1ce X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Fri, 20 Mar 2009 10:24:52 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 50d8b58c48c7acb4f4ed80c24593ffe2a9c7d1ce Gitweb: http://git.kernel.org/tip/50d8b58c48c7acb4f4ed80c24593ffe2a9c7d1ce Author: Peter Zijlstra AuthorDate: Thu, 19 Mar 2009 20:26:11 +0100 Committer: Ingo Molnar CommitDate: Fri, 20 Mar 2009 11:15:11 +0100 perf_counter: fix uninitialized usage of event_list Impact: fix boot crash When doing the generic context switch event I ran into some early boot hangs, which were caused by inf func recursion (event, fault, event, fault). I eventually tracked it down to event_list not being initialized at the time of the first event. Fix this. Signed-off-by: Peter Zijlstra Cc: Paul Mackerras Cc: Steven Rostedt LKML-Reference: <20090319194233.195392657@chello.nl> Signed-off-by: Ingo Molnar --- include/linux/init_task.h | 2 ++ kernel/perf_counter.c | 2 +- 2 files changed, 3 insertions(+), 1 deletions(-) diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 219748d..ca226a9 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -124,6 +124,8 @@ extern struct cred init_cred; # define INIT_PERF_COUNTERS(tsk) \ .perf_counter_ctx.counter_list = \ LIST_HEAD_INIT(tsk.perf_counter_ctx.counter_list), \ + .perf_counter_ctx.event_list = \ + LIST_HEAD_INIT(tsk.perf_counter_ctx.event_list), \ .perf_counter_ctx.lock = \ __SPIN_LOCK_UNLOCKED(tsk.perf_counter_ctx.lock), #else diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index b39456a..4c4e9eb 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1506,7 +1506,7 @@ static void perf_swcounter_ctx_event(struct perf_counter_context *ctx, { struct perf_counter *counter; - if (list_empty(&ctx->event_list)) + if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list)) return; rcu_read_lock();