From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932402AbaFUA4w (ORCPT ); Fri, 20 Jun 2014 20:56:52 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:33955 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757365AbaFUA4v (ORCPT ); Fri, 20 Jun 2014 20:56:51 -0400 Date: Fri, 20 Jun 2014 17:56:48 -0700 From: Andrew Morton To: Sasha Levin Cc: Johannes Weiner , Michal Hocko , Hugh Dickins , Tejun Heo , Vladimir Davydov , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [patch 13/13] mm: memcontrol: rewrite uncharge API Message-Id: <20140620175648.666cae72.akpm@linux-foundation.org> In-Reply-To: <53A4D323.5080808@oracle.com> References: <1403124045-24361-1-git-send-email-hannes@cmpxchg.org> <1403124045-24361-14-git-send-email-hannes@cmpxchg.org> <53A4D323.5080808@oracle.com> X-Mailer: Sylpheed 2.7.1 (GTK+ 2.18.9; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 20 Jun 2014 20:34:43 -0400 Sasha Levin wrote: > I'm seeing the following when booting a VM, bisection pointed me to this > patch. > > [ 32.830823] BUG: using __this_cpu_add() in preemptible [00000000] code: mkdir/8677 Thanks. This one was fixed earlier today. From: Michal Hocko Subject: memcg: mem_cgroup_charge_statistics needs preempt_disable preempt_disable was previously disabled by lock_page_cgroup which has been removed by "mm: memcontrol: rewrite uncharge API". This fixes the a flood of splats like this: [ 3.149371] BUG: using __this_cpu_add() in preemptible [00000000] code: udevd/1271 [ 3.151458] caller is __this_cpu_preempt_check+0x13/0x15 [ 3.152927] CPU: 0 PID: 1271 Comm: udevd Not tainted 3.15.0-test1 #366 [ 3.154637] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 3.156788] 0000000000000000 ffff88000005fba8 ffffffff814efe3f 0000000000000000 [ 3.158810] ffff88000005fbd8 ffffffff8125b969 ffff880007413448 0000000000000001 [ 3.160836] ffffea00001e8c00 0000000000000001 ffff88000005fbe8 ffffffff8125b9a8 [ 3.162950] Call Trace: [ 3.163598] [] dump_stack+0x4e/0x7a [ 3.164942] [] check_preemption_disabled+0xd2/0xe5 [ 3.166618] [] __this_cpu_preempt_check+0x13/0x15 [ 3.168267] [] mem_cgroup_charge_statistics.isra.36+0xb5/0xc6 [ 3.170169] [] commit_charge+0x23c/0x256 [ 3.171823] [] mem_cgroup_commit_charge+0xb8/0xd7 [ 3.173838] [] shmem_getpage_gfp+0x399/0x605 [ 3.175363] [] shmem_write_begin+0x3d/0x58 [ 3.176854] [] generic_perform_write+0xbc/0x192 [ 3.178445] [] ? file_update_time+0x34/0xac [ 3.179952] [] __generic_file_aio_write+0x2c0/0x300 [ 3.181655] [] generic_file_aio_write+0x52/0xbd [ 3.183234] [] do_sync_write+0x59/0x78 [ 3.184630] [] vfs_write+0xc4/0x181 [ 3.185957] [] SyS_write+0x4a/0x91 [ 3.187258] [] tracesys+0xd0/0xd5 Signed-off-by: Michal Hocko Cc: Johannes Weiner Signed-off-by: Andrew Morton --- mm/memcontrol.c | 3 +++ 1 file changed, 3 insertions(+) diff -puN mm/memcontrol.c~mm-memcontrol-rewrite-uncharge-api-fix-4 mm/memcontrol.c --- a/mm/memcontrol.c~mm-memcontrol-rewrite-uncharge-api-fix-4 +++ a/mm/memcontrol.c @@ -904,6 +904,8 @@ static void mem_cgroup_charge_statistics struct page *page, int nr_pages) { + preempt_disable(); + /* * Here, RSS means 'mapped anon' and anon's SwapCache. Shmem/tmpfs is * counted as CACHE even if it's on ANON LRU. @@ -928,6 +930,7 @@ static void mem_cgroup_charge_statistics } __this_cpu_add(memcg->stat->nr_page_events, nr_pages); + preempt_enable(); } unsigned long mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru) _