From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751477AbaCXEpI (ORCPT ); Mon, 24 Mar 2014 00:45:08 -0400 Received: from mail-ve0-f172.google.com ([209.85.128.172]:64980 "EHLO mail-ve0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751018AbaCXEpE (ORCPT ); Mon, 24 Mar 2014 00:45:04 -0400 MIME-Version: 1.0 In-Reply-To: <20140323150754.272874059@linutronix.de> References: <20140323150557.288925975@linutronix.de> <20140323150754.272874059@linutronix.de> Date: Mon, 24 Mar 2014 10:15:02 +0530 X-Google-Sender-Auth: igX7NszJvOrrh-cc2BIhUBN3dDw Message-ID: Subject: Re: [patch 15/16] cpufreq: intel-pstate: Use del_timer_sync in intel_pstate_cpu_exit() From: Viresh Kumar To: Thomas Gleixner Cc: LKML , Julia Lawall , Andrew Morton , "Rafael J. Wysocki" , cpufreq , pm Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Mar 23, 2014 at 8:39 PM, Thomas Gleixner wrote: > We are about to free the data structure. Make sure no timer callback > is running. I might be paranoid, but the ->exit callback can be > invoked from so many places, that it is not entirely clear whether > del_timer is always called on the cpu on which it is enqueued. In normal cases it will be called only when CPU goes offline and I hope that isn't called on the dying CPU. > While looking through the call sites I noticed, that > cpufreq_init_policy() can fail and invoke cpufreq_driver->exit() but > it does not return the failure and the callsite happily proceeds. Thanks for reporting this, will get it fixed. > Signed-off-by: Thomas Gleixner > Cc: "Rafael J. Wysocki" > Cc: cpufreq > Cc: pm > --- > > drivers/cpufreq/intel_pstate.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > Index: tip/drivers/cpufreq/intel_pstate.c > =================================================================== > --- tip.orig/drivers/cpufreq/intel_pstate.c > +++ tip/drivers/cpufreq/intel_pstate.c > @@ -777,7 +777,7 @@ static int intel_pstate_cpu_exit(struct > { > int cpu = policy->cpu; > > - del_timer(&all_cpu_data[cpu]->timer); > + del_timer_sync(&all_cpu_data[cpu]->timer); Acked-by: Viresh Kumar