Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751873AbcDFRGG (ORCPT ); Wed, 6 Apr 2016 13:06:06 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:46532 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1750847AbcDFRGE convert rfc822-to-8bit (ORCPT ); Wed, 6 Apr 2016 13:06:04 -0400 X-IronPort-AV: E=Sophos;i="5.22,518,1449504000"; d="scan'208";a="5332379" From: Zhao Lei To: "'Srikar Dronamraju'" , "'Anton Blanchard'" CC: "'Peter Zijlstra'" , "'Ingo Molnar'" , , , , , , , , , "'Stephen Rothwell'" , "'Michael Ellerman'" , References: <20160404140312.GA28495@linux.vnet.ibm.com> <20160406065436.GB3078@gmail.com> <20160406203219.788ae7cf@kryten> <20160406110803.GI2906@worktop> <20160406215950.04bc3f0b@kryten> <20160406132637.GA2108@linux.vnet.ibm.com> In-Reply-To: <20160406132637.GA2108@linux.vnet.ibm.com> Subject: RE: [PATCH] sched/cpuacct: Check for NULL when using task_pt_regs() Date: Thu, 7 Apr 2016 01:05:52 +0800 Message-ID: <000101d19026$94249f00$bc6ddd00$@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8BIT X-Mailer: Microsoft Outlook 15.0 Thread-Index: AQJv7eQQvUiXwYUH3DrsRFUSXIIVxAIjY5GlAurW/AEBVS8BcwEtxKEaAT+vGVoBU4r2CQECAWtwnec9UrA= Content-Language: zh-cn X-yoursite-MailScanner-ID: A08C9408D260.ADB27 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: zhaolei@cn.fujitsu.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2334 Lines: 99 > -----Original Message----- > From: Srikar Dronamraju [mailto:srikar@linux.vnet.ibm.com] > Sent: Wednesday, April 06, 2016 9:27 PM > To: Anton Blanchard > Cc: Peter Zijlstra ; Ingo Molnar ; > tglx@linutronix.de; efault@gmx.de; htejun@gmail.com; > linux-kernel@vger.kernel.org; tj@kernel.org; torvalds@linux-foundation.org; > zhaolei@cn.fujitsu.com; yangds.fnst@cn.fujitsu.com; hpa@zytor.com; Stephen > Rothwell ; Michael Ellerman ; > linuxppc-dev@lists.ozlabs.org > Subject: Re: [PATCH] sched/cpuacct: Check for NULL when using task_pt_regs() > > * Anton Blanchard [2016-04-06 21:59:50]: > > > Looks good, and the patch below does fix the oops for me. > > > > Anton > > -- > > > > task_pt_regs() can return NULL for kernel threads, so add a check. > > This fixes an oops at boot on ppc64. > > > > Signed-off-by: Anton Blanchard > > Works for me too. > > Reported-and-Tested-by: Srikar Dronamraju > Thanks, all I tested it in the vm(can not boot before fix): [single cpu] # for f in cpuacct.*; do echo "$f: "; cat $f; done cpuacct.stat: user 260 system 451 cpuacct.usage: 6923456654 cpuacct.usage_percpu: 6963446178 cpuacct.usage_percpu_sys: 2610934362 cpuacct.usage_percpu_user: 4451667140 cpuacct.usage_sys: 2612684054 cpuacct.usage_user: 4540275322 # [2 cpu wih 8 maxcpus] # for f in cpuacct.*; do echo "$f: "; cat $f; done cpuacct.stat: user 205 system 536 cpuacct.usage: 7293688020 cpuacct.usage_percpu: 3785674990 3551323200 0 0 0 0 0 0 cpuacct.usage_percpu_sys: 2227281124 1635060584 0 0 0 0 0 0 cpuacct.usage_percpu_user: 1567487176 1992278818 0 0 0 0 0 0 cpuacct.usage_sys: 3863445982 cpuacct.usage_user: 3643874038 # # cat /proc/cpuinfo processor : 0 cpu : POWER7 (raw), altivec supported clock : 1000.000000MHz revision : 2.3 (pvr 003f 0203) processor : 1 cpu : POWER7 (raw), altivec supported clock : 1000.000000MHz revision : 2.3 (pvr 003f 0203) timebase : 512000000 platform : pSeries model : IBM pSeries (emulated by qemu) machine : CHRP IBM pSeries (emulated by qemu) # Thanks Zhaolei > -- > Thanks and Regards > Srikar Dronamraju >