linux-kernel - Re: process hangs on do

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 19 Oct 2012 18:04:25 +0200
From:	Michal Hocko <mhocko@...e.cz>
To:	gaoqiang <gaoqiangscut@...il.com>
Cc:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-mmc@...r.kernel.org" <linux-mmc@...r.kernel.org>,
	"cgroups@...r.kernel.org" <cgroups@...r.kernel.org>,
	linux-mm@...ck.org
Subject: Re: process hangs on do_exit when oom happens

On Wed 17-10-12 18:23:34, gaoqiang wrote:
> I looked up nothing useful with google,so I'm here for help..
> 
> when this happens:  I use memcg to limit the memory use of a
> process,and when the memcg cgroup was out of memory,
> the process was oom-killed   however,it cannot really complete the
> exiting. here is the some information

How many tasks are in the group and what kind of memory do they use?
Is it possible that you were hit by the same issue as described in 
79dfdacc memcg: make oom_lock 0 and 1 based rather than counter.

> OS version:  centos6.2    2.6.32.220.7.1

Your kernel is quite old and you should be probably asking your
distribution to help you out. There were many fixes since 2.6.32.
Are you able to reproduce the same issue with the current vanila kernel?

> /proc/pid/stack
> ---------------------------------------------------------------
> 
> [<ffffffff810597ca>] __cond_resched+0x2a/0x40
> [<ffffffff81121569>] unmap_vmas+0xb49/0xb70
> [<ffffffff8112822e>] exit_mmap+0x7e/0x140
> [<ffffffff8105b078>] mmput+0x58/0x110
> [<ffffffff81061aad>] exit_mm+0x11d/0x160
> [<ffffffff81061c9d>] do_exit+0x1ad/0x860
> [<ffffffff81062391>] do_group_exit+0x41/0xb0
> [<ffffffff81077cd8>] get_signal_to_deliver+0x1e8/0x430
> [<ffffffff8100a4c4>] do_notify_resume+0xf4/0x8b0
> [<ffffffff8100b281>] int_signal+0x12/0x17
> [<ffffffffffffffff>] 0xffffffffffffffff

This looks strange because this is just an exit part which shouldn't
deadlock or anything. Is this stack stable? Have you tried to take check
it more times?

-- 
Michal Hocko
SUSE Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/