public inbox for linux-nfs@vger.kernel.org
 help / color / mirror / Atom feed
From: Zdenek Kabelac <zdenek.kabelac@gmail.com>
To: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Cc: linux-nfs@vger.kernel.org
Subject: INFO: suspicious rcu_dereference_check()
Date: Thu, 25 Mar 2010 11:48:49 +0100	[thread overview]
Message-ID: <c4e36d111003250348q678eb2e6w4f3e8133e7fd6e58@mail.gmail.com> (raw)

Hi

I've enabled rcu correctness for my  todays 2.6.34-rc2 kernel.

I'm getting this INFO: from my kvm guest (which uses host's nfs
exported directory.)
This

===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
fs/nfs/delegation.c:348 invoked rcu_dereference_check() without protection!

other info that might help us debug this:


rcu_scheduler_active = 1, debug_locks = 0
2 locks held by rm/1820:
 #0:  (&sb->s_type->i_mutex_key#13/1){+.+.+.}, at:
[<ffffffff81138e1b>] do_unlinkat+0x9b/0x1c0
 #1:  (&sb->s_type->i_mutex_key#13){+.+.+.}, at: [<ffffffff81136a76>]
vfs_unlink+0x56/0xf0

stack backtrace:
Pid: 1820, comm: rm Not tainted 2.6.34-rc2-00186-ge79a302 #60
Call Trace:
 [<ffffffff810819fb>] lockdep_rcu_dereference+0xbb/0xc0
 [<ffffffffa0228351>] nfs_inode_return_delegation+0x101/0x110 [nfs]
 [<ffffffffa01fd58d>] nfs_unlink+0xad/0x2a0 [nfs]
 [<ffffffff81136aba>] vfs_unlink+0x9a/0xf0
 [<ffffffff81148365>] ? mnt_want_write+0x65/0xb0
 [<ffffffff81138f03>] do_unlinkat+0x183/0x1c0
 [<ffffffff8142b66d>] ? retint_swapgs+0xe/0x13
 [<ffffffff81083985>] ? trace_hardirqs_on_caller+0x155/0x1a0
 [<ffffffff8142a232>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff811390a2>] sys_unlinkat+0x22/0x40
 [<ffffffff81031dc8>] sysenter_dispatch+0x7/0x2c


Zdenek

             reply	other threads:[~2010-03-25 10:48 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-25 10:48 Zdenek Kabelac [this message]
     [not found] ` <c4e36d111003250348q678eb2e6w4f3e8133e7fd6e58-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2010-03-25 15:36   ` INFO: suspicious rcu_dereference_check() Trond Myklebust
     [not found]     ` <1269531400.3648.1.camel-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2010-03-29 15:25       ` Paul E. McKenney
2010-03-29 17:14         ` Trond Myklebust
     [not found]         ` <1269882883.3181.25.camel-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2010-03-29 18:56           ` David Howells

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=c4e36d111003250348q678eb2e6w4f3e8133e7fd6e58@mail.gmail.com \
    --to=zdenek.kabelac@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nfs@vger.kernel.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