Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934571AbcDMLwe (ORCPT ); Wed, 13 Apr 2016 07:52:34 -0400 Received: from terminus.zytor.com ([198.137.202.10]:57372 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934540AbcDMLwc (ORCPT ); Wed, 13 Apr 2016 07:52:32 -0400 Date: Wed, 13 Apr 2016 04:49:34 -0700 From: tip-bot for Anton Blanchard Message-ID: Cc: hpa@zytor.com, anton@samba.org, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, sfr@canb.auug.org.au, peterz@infradead.org, mpe@ellerman.id.au, zhaolei@cn.fujitsu.com, mingo@kernel.org, srikar@linux.vnet.ibm.com, tglx@linutronix.de Reply-To: srikar@linux.vnet.ibm.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, sfr@canb.auug.org.au, peterz@infradead.org, mingo@kernel.org, zhaolei@cn.fujitsu.com, mpe@ellerman.id.au, anton@samba.org, hpa@zytor.com, torvalds@linux-foundation.org In-Reply-To: <20160406215950.04bc3f0b@kryten> References: <20160406215950.04bc3f0b@kryten> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/cpuacct: Check for NULL when using task_pt_regs() Git-Commit-ID: bd92883051a0228cc34996b8e766111ba10c9aac X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1763 Lines: 52 Commit-ID: bd92883051a0228cc34996b8e766111ba10c9aac Gitweb: http://git.kernel.org/tip/bd92883051a0228cc34996b8e766111ba10c9aac Author: Anton Blanchard AuthorDate: Wed, 6 Apr 2016 21:59:50 +1000 Committer: Ingo Molnar CommitDate: Wed, 13 Apr 2016 13:22:37 +0200 sched/cpuacct: Check for NULL when using task_pt_regs() task_pt_regs() can return NULL for kernel threads, so add a check. This fixes an oops at boot on ppc64. Reported-and-Tested-by: Srikar Dronamraju Tested-by: Zhao Lei Signed-off-by: Anton Blanchard Acked-by: Zhao Lei Cc: Linus Torvalds Cc: Michael Ellerman Cc: Peter Zijlstra Cc: Stephen Rothwell Cc: Thomas Gleixner Cc: efault@gmx.de Cc: htejun@gmail.com Cc: linuxppc-dev@lists.ozlabs.org Cc: tj@kernel.org Cc: yangds.fnst@cn.fujitsu.com Link: http://lkml.kernel.org/r/20160406215950.04bc3f0b@kryten Signed-off-by: Ingo Molnar --- kernel/sched/cpuacct.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c index df947e0..41f85c4 100644 --- a/kernel/sched/cpuacct.c +++ b/kernel/sched/cpuacct.c @@ -316,12 +316,11 @@ static struct cftype files[] = { void cpuacct_charge(struct task_struct *tsk, u64 cputime) { struct cpuacct *ca; - int index; + int index = CPUACCT_USAGE_SYSTEM; + struct pt_regs *regs = task_pt_regs(tsk); - if (user_mode(task_pt_regs(tsk))) + if (regs && user_mode(regs)) index = CPUACCT_USAGE_USER; - else - index = CPUACCT_USAGE_SYSTEM; rcu_read_lock();