From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752486AbaCJHSS (ORCPT ); Mon, 10 Mar 2014 03:18:18 -0400 Received: from tama500.ecl.ntt.co.jp ([129.60.39.148]:57301 "EHLO tama500.ecl.ntt.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752026AbaCJHSQ (ORCPT ); Mon, 10 Mar 2014 03:18:16 -0400 Message-ID: <531D66FE.20703@lab.ntt.co.jp> Date: Mon, 10 Mar 2014 16:17:18 +0900 From: =?UTF-8?B?RmVybmFuZG8gTHVpcyBWw6F6cXVleiBDYW8=?= User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 MIME-Version: 1.0 To: Steven Rostedt CC: Peter Zijlstra , Linus Torvalds , Andrew Morton , Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: [PATCH] sched/clock: prevent tracing recursion in sched_clock_cpu() References: <1394083528.4524.3.camel@nexus> <20140306055113.2306397d@gandalf.local.home> In-Reply-To: <20140306055113.2306397d@gandalf.local.home> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-MML: No Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/06/2014 07:51 PM, Steven Rostedt wrote: > On Thu, 06 Mar 2014 14:25:28 +0900 > Fernando Luis Vázquez Cao wrote: > >> From: Fernando Luis Vazquez Cao >> >> Prevent tracing of preempt_disable/enable() in sched_clock_cpu(). >> When CONFIG_DEBUG_PREEMPT is enabled, preempt_disable/enable() are >> traced and this causes trace_clock() users (and probably others) to >> go into an infinite recursion. Systems with a stable sched_clock() >> are not affected. >> >> This problem is similar to that fixed by upstream commit 95ef1e52922 >> ("KVM guest: prevent tracing recursion with kvmclock"). > Also similar to: 569d6557ab957. > > Acked-by: Steven Rostedt Thank you four your review, Peter, Steven. By the way, who is going to pick this patch? Do you want me to resend with Steven's Acked-by added? - Fernando