From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751738Ab3IQE6j (ORCPT ); Tue, 17 Sep 2013 00:58:39 -0400 Received: from mga14.intel.com ([143.182.124.37]:58151 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751462Ab3IQE6g (ORCPT ); Tue, 17 Sep 2013 00:58:36 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.90,920,1371106800"; d="scan'208";a="295727995" Message-ID: <5237E17A.80603@intel.com> Date: Tue, 17 Sep 2013 12:58:34 +0800 From: "Yan, Zheng" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130805 Thunderbird/17.0.8 MIME-Version: 1.0 To: Peter Zijlstra CC: eranian@google.com, Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: [BUG] uncore_pmu_event_init: using smp_processor_id() in preemptible core References: <20130916092110.GA29018@twins.programming.kicks-ass.net> In-Reply-To: <20130916092110.GA29018@twins.programming.kicks-ass.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/16/2013 05:21 PM, Peter Zijlstra wrote: > Hi, > > Trinity just triggered this: > > [ 595.847438] BUG: using smp_processor_id() in preemptible [00000000] code: trinity-child28/2674 > [ 595.857378] caller is uncore_pmu_event_init+0x114/0x270 > [ 595.863262] CPU: 11 PID: 2674 Comm: trinity-child28 Tainted: G W 3.11.0+ #365 > [ 595.872146] Hardware name: Supermicro X8DTN/X8DTN, BIOS 4.6.3 01/08/2010 > [ 595.879656] 000000000000000b ffff880433e09d98 ffffffff81642eb8 ffff880433e09fd8 > [ 595.888430] ffff880433e09dc0 ffffffff81367d1e ffff880373621000 ffff880435bacc00 > [ 595.897330] 0000000000000000 ffff880433e09df8 ffffffff81068394 ffffffff81068285 > [ 595.906252] Call Trace: > [ 595.909127] [] dump_stack+0x4e/0x82 > [ 595.914925] [] debug_smp_processor_id+0xde/0x100 > [ 595.921903] [] uncore_pmu_event_init+0x114/0x270 > [ 595.928907] [] ? uncore_pmu_event_init+0x5/0x270 > [ 595.935806] [] perf_init_event+0xcc/0x190 > > That's in uncore_validate_group() where we allocate the fake_box(). > > I'm thinking we might as well use raw_smp_processor_id() since it really > doesn't matter where the fake box lives. > > --- > arch/x86/kernel/cpu/perf_event_intel_uncore.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c > index 8ed4458..63c8913 100644 > --- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c > +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c > @@ -3031,7 +3031,7 @@ static int uncore_validate_group(struct intel_uncore_pmu *pmu, > struct intel_uncore_box *fake_box; > int ret = -EINVAL, n; > > - fake_box = uncore_alloc_box(pmu->type, smp_processor_id()); > + fake_box = uncore_alloc_box(pmu->type, raw_smp_processor_id()); > if (!fake_box) > return -ENOMEM; > > how about using kzalloc() in this case. --- diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c index fd8011e..a12a22f 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c @@ -2713,7 +2713,10 @@ struct intel_uncore_box *uncore_alloc_box(struct intel_uncore_type *type, int cp size = sizeof(*box) + type->num_shared_regs * sizeof(struct intel_uncore_extra_reg); - box = kzalloc_node(size, GFP_KERNEL, cpu_to_node(cpu)); + if (cpu < 0) + box = kzalloc(size, GFP_KERNEL); + else + box = kzalloc_node(size, GFP_KERNEL, cpu_to_node(cpu)); if (!box) return NULL; @@ -3031,7 +3034,7 @@ static int uncore_validate_group(struct intel_uncore_pmu *pmu, struct intel_uncore_box *fake_box; int ret = -EINVAL, n; - fake_box = uncore_alloc_box(pmu->type, smp_processor_id()); + fake_box = uncore_alloc_box(pmu->type, -1); if (!fake_box) return -ENOMEM;