Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759774Ab3EWP1H (ORCPT ); Thu, 23 May 2013 11:27:07 -0400 Received: from 173-166-109-252-newengland.hfc.comcastbusiness.net ([173.166.109.252]:34246 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759756Ab3EWP1E (ORCPT ); Thu, 23 May 2013 11:27:04 -0400 Date: Thu, 23 May 2013 17:26:57 +0200 From: Peter Zijlstra To: Vince Weaver Cc: linux-kernel@vger.kernel.org, Paul Mackerras , Ingo Molnar , Arnaldo Carvalho de Melo , trinity@vger.kernel.org Subject: Re: WARNING in arch/x86/kernel/cpu/perf_event.c Message-ID: <20130523152657.GF23650@twins.programming.kicks-ass.net> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 983 Lines: 28 On Thu, May 23, 2013 at 10:29:07AM -0400, Vince Weaver wrote: > Hello, > > so now that I got past the OOPS in perf_mmap_close() I re-ran > the fuzzer and quickly encountered the following WARNing. > > It happens here: > > static void x86_pmu_start(struct perf_event *event, int flags) > { > struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); > int idx = event->hw.idx; > > if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED))) > return; > > > Is it worth trying to come up with a reproducible case for this one? > > I never know how seriously to take WARN_ON_ONCE dumps. Its not supposed to happen, you're trying to start an already running event. I'll put it on the todo list. -- 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/