From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936046AbbCDIIv (ORCPT ); Wed, 4 Mar 2015 03:08:51 -0500 Received: from szxga03-in.huawei.com ([119.145.14.66]:8316 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933624AbbCDIIs (ORCPT ); Wed, 4 Mar 2015 03:08:48 -0500 Message-ID: <54F6BD83.5000202@huawei.com> Date: Wed, 4 Mar 2015 16:08:35 +0800 From: Zefan Li User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: Ming Lei CC: Linux Kernel Mailing List , Tejun Heo Subject: Re: 4.0.0-rc1-next-20150303: cgroup: BUG: unable to handle kernel NULL pointer dereference at References: In-Reply-To: X-Enigmail-Version: 1.6 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.18.230] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020205.54F6BD89.0163,ss=1,re=0.001,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: dec75edbce284ced2bb74be6a539dde0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Caused by this commit: 295458e67284f57d1 cgroup: call cgroup_subsys->bind on cgroup subsys initialization cpuset_init() is called after cgroup_init(), so when cgroup_init() calls cpuset_bind() top_cpuset.cpus_allowed is NULL. I'll send out a fix soon. On 2015/3/4 13:17, Ming Lei wrote: > Hi Guys, > > [ 0.014166] BUG: unable to handle kernel NULL pointer dereference > at (null)^M > [ 0.014920] IP: [] cpumask_copy+0x17/0x1a^M > [ 0.015000] PGD 0 ^M > [ 0.015000] Oops: 0002 [#1] PREEMPT SMP DEBUG_PAGEALLOC ^M > [ 0.015000] Dumping ftrace buffer:^M > [ 0.015000] (ftrace buffer empty)^M > [ 0.015000] Modules linked in:^M > [ 0.015000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted > 4.0.0-rc1-next-20150303 #123^M > [ 0.015000] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), > BIOS Bochs 01/01/2011^M > [ 0.015000] task: ffffffff81a10460 ti: ffffffff81a00000 task.ti: > ffffffff81a00000^M > [ 0.015000] RIP: 0010:[] [] > cpumask_copy+0x17/0x1a^M > [ 0.015000] RSP: 0000:ffffffff81a03f00 EFLAGS: 00010002^M > [ 0.015000] RAX: ffffffff81e7aa80 RBX: ffffffff81a96060 RCX: > 0000000000000008^M > [ 0.015000] RDX: ffffffff81a96000 RSI: ffffffff81b19f10 RDI: > 0000000000000000^M > [ 0.015000] RBP: ffffffff81a03f18 R08: 00000000000000d0 R09: > ffff880235138120^M > [ 0.015000] R10: 0000000000000000 R11: 0000000000017078 R12: > ffffffff81a94dc0^M > [ 0.015000] R13: ffffffff81e7aba0 R14: 0000000000000000 R15: > 0000000000000000^M > [ 0.015000] FS: 0000000000000000(0000) GS:ffff88023ec00000(0000) > knlGS:0000000000000000^M > [ 0.015000] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b^M > [ 0.015000] CR2: 0000000000000000 CR3: 0000000001a0b000 CR4: > 00000000000006b0^M > [ 0.015000] Stack:^M > [ 0.015000] ffffffff810ab202 ffffffff81a96000 ffffffff81a952d0 > ffffffff81a03f68^M > [ 0.015000] ffffffff81b557ae 0000000000000000 ffffffff81a95fa0 > ffffffffffffffff^M > [ 0.015000] ffffffffffffffff ffffffff81bc88d0 ffff88023efa4480 > ffffffff81bd02c0^M > [ 0.015000] Call Trace:^M > [ 0.015000] [] ? cpuset_bind+0x50/0x99^M > [ 0.015000] [] cgroup_init+0x1ef/0x27b^M > [ 0.015000] [] start_kernel+0x3fa/0x43f^M > [ 0.015000] [] ? set_init_arg+0x55/0x55^M > [ 0.015000] [] x86_64_start_reservations+0x2a/0x2c^M > [ 0.015000] [] x86_64_start_kernel+0x102/0x106^M > [ 0.015000] Code: 15 29 04 a7 00 48 89 e5 e8 3b 4d 20 00 85 c0 0f > 95 c0 5d c3 8b 0d 14 04 a7 00 55 48 89 e5 5d 48 83 c1 3f 48 c1 e9 06 > 48 c1 e1 03 a4 c3 55 8b 35 f9 03 a7 00 48 89 e5 e8 7f 4c 20 00 85 > c0 0f ^M > [ 0.015000] RIP [] cpumask_copy+0x17/0x1a^M > [ 0.015000] RSP ^M > [ 0.015000] CR2: 0000000000000000^M > [ 0.015000] ---[ end trace 15a4fd3fb5107ec6 ]---^M > [ 0.015000] Kernel panic - not syncing: Attempted to kill the idle task!^M > [ 0.015000] Dumping ftrace buffer:^M > [ 0.015000] (ftrace buffer empty)^M > > > Thanks, > Ming Lei > . >