cgroups.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sasha Levin <sasha.levin-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
To: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
	Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
Cc: Dave Jones <davej-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
	Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
	"linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
	<linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
Subject: cgroup: INFO: suspicious RCU usage. in cgroup_name
Date: Wed, 06 Mar 2013 11:02:06 -0500	[thread overview]
Message-ID: <5137687E.50701@oracle.com> (raw)

Hi all,

While fuzzing with trinity inside a KVM tools guest running latest -next kernel
I've stumbled on the following:

[  450.180599] ===============================
[  450.181392] [ INFO: suspicious RCU usage. ]
[  450.182101] 3.9.0-rc1-next-20130305-sasha-00048-g35e9ec5-dirty #1032 Tainted: G        W
[  450.183482] -------------------------------
[  450.184343] include/linux/cgroup.h:429 suspicious rcu_dereference_check() usage!
[  450.185575]
[  450.185575] other info that might help us debug this:
[  450.185575]
[  450.186961]
[  450.186961] rcu_scheduler_active = 1, debug_locks = 1
[  450.188001] 4 locks held by kworker/u:0/6:
[  450.188646]  #0:  (khelper){.+.+.+}, at: [<ffffffff8112ba98>] process_one_work+0x238/0x570
[  450.190186]  #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8112ba98>] process_one_work+0x238/0x570
[  450.191824]  #2:  (&(&p->alloc_lock)->rlock){+.+.-.}, at: [<ffffffff812036d3>] dump_header+0x43/0xe0
[  450.193366]  #3:  (cpuset_buffer_lock){+.+...}, at: [<ffffffff811a06d0>] cpuset_print_task_mems_allowed+0x60/0x150
[  450.195281]
[  450.195281] stack backtrace:
[  450.195987] Pid: 6, comm: kworker/u:0 Tainted: G        W    3.9.0-rc1-next-20130305-sasha-00048-g35e9ec5-dirty #1032
[  450.197678] Call Trace:
[  450.198086]  [<ffffffff811793b3>] lockdep_rcu_suspicious+0x113/0x130
[  450.199077]  [<ffffffff811a0757>] cpuset_print_task_mems_allowed+0xe7/0x150
[  450.200263]  [<ffffffff8120370c>] dump_header+0x7c/0xe0
[  450.201135]  [<ffffffff81203972>] oom_kill_process+0x82/0x370
[  450.202048]  [<ffffffff812040cb>] out_of_memory+0x1ab/0x200
[  450.202921]  [<ffffffff83d44e00>] ? _raw_write_unlock_irq+0x50/0x80
[  450.204068]  [<ffffffff8120ad1f>] __alloc_pages_slowpath+0x5bf/0x700
[  450.205075]  [<ffffffff8120b135>] __alloc_pages_nodemask+0x2d5/0x400
[  450.206067]  [<ffffffff811047c8>] dup_task_struct+0x68/0x1c0
[  450.206975]  [<ffffffff81105b19>] copy_process+0xe9/0xfd0
[  450.207798]  [<ffffffff8114dd25>] ? sched_clock_local+0x25/0x90
[  450.208679]  [<ffffffff81127c50>] ? call_helper+0x20/0x20
[  450.209496]  [<ffffffff81106e6b>] do_fork+0xbb/0x280
[  450.210384]  [<ffffffff811070b1>] kernel_thread+0x21/0x30
[  450.211323]  [<ffffffff81127a93>] __call_usermodehelper+0x33/0xa0
[  450.212260]  [<ffffffff8112bbc8>] process_one_work+0x368/0x570
[  450.213201]  [<ffffffff8112ba98>] ? process_one_work+0x238/0x570
[  450.214248]  [<ffffffff8112d735>] worker_thread+0x1f5/0x340
[  450.215159]  [<ffffffff8112d540>] ? manage_workers+0x160/0x160
[  450.216078]  [<ffffffff81135ec2>] kthread+0xe2/0xf0
[  450.216901]  [<ffffffff8117e34a>] ? __lock_release+0x1da/0x1f0
[  450.217824]  [<ffffffff81135de0>] ? __init_kthread_worker+0x70/0x70
[  450.218791]  [<ffffffff83d4ddbc>] ret_from_fork+0x7c/0xb0
[  450.219627]  [<ffffffff81135de0>] ? __init_kthread_worker+0x70/0x70
[  450.220780] kworker/u:0 cpuset=/ mems_allowed=0

The offending commit looks like "cgroup: fix cgroup_path() vs rename() race".


Thanks,
Sasha

             reply	other threads:[~2013-03-06 16:02 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-06 16:02 Sasha Levin [this message]
     [not found] ` <5137687E.50701-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
2013-03-07  2:29   ` cgroup: INFO: suspicious RCU usage. in cgroup_name Li Zefan
2013-03-07  6:15   ` Michael Wang
     [not found]     ` <5138309A.2060804-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
2013-03-07  6:21       ` Li Zefan

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=5137687E.50701@oracle.com \
    --to=sasha.levin-qhclzuegtsvqt0dzr+alfa@public.gmane.org \
    --cc=cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=davej-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \
    --cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org \
    --cc=tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).