From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752970Ab1J1Gf7 (ORCPT ); Fri, 28 Oct 2011 02:35:59 -0400 Received: from out5.smtp.messagingengine.com ([66.111.4.29]:48955 "EHLO out5.smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750730Ab1J1Gf6 (ORCPT ); Fri, 28 Oct 2011 02:35:58 -0400 X-Sasl-enc: HmFppIbU1Zw/Q391fpm0AAaIpMXm4LGJNI8g8p5iYzzM 1319783756 Subject: Re: INFO: possible recursive locking detected: autofs4_expire_indirect() From: Ian Kent To: Nick Bowler Cc: Pawel Sikora , linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, viro@zeniv.linux.org.uk, arekm@pld-linux.org, Steven Rostedt In-Reply-To: <20111027133118.GA17916@elliptictech.com> References: <3620801.NcMcO2jnH8@pawels> <20111027133118.GA17916@elliptictech.com> Content-Type: text/plain; charset="UTF-8" Date: Fri, 28 Oct 2011 14:35:51 +0800 Message-ID: <1319783751.3214.9.camel@perseus.themaw.net> Mime-Version: 1.0 X-Mailer: Evolution 2.32.3 (2.32.3-1.fc14) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2011-10-27 at 09:31 -0400, Nick Bowler wrote: > On 2011-10-25 14:48 +0200, Pawel Sikora wrote: > > the nfs client/server with fresh 3.0.8 + vserver + enabled debug options reports attached info. > > afaics, the vserver doesn't change autofs code, so it looks like a pure vanilla problem. > > I reported this issue a long time ago, and a patch[1] was provided > quickly, but it seems that for some reason it never made it to mainline. > > Adding Steven to CC. > > [1] http://permalink.gmane.org/gmane.linux.kernel/1129741 And when nothing happened I forwarded the patch to Al Viro. Sounds like it's time to re-post this one, and I'll ack it. > > > [ 3708.715749] ============================================= > > [ 3708.715940] [ INFO: possible recursive locking detected ] > > [ 3708.716040] 3.0.8-vs2.3.1-dirty #6 > > [ 3708.716131] --------------------------------------------- > > [ 3708.716230] automount/29215 is trying to acquire lock: > > [ 3708.716301] (&(&dentry->d_lock)->rlock/1){+.+...}, at: [] autofs4_expire_indirect+0xe0/0x4e0 [autofs4] > > [ 3708.716301] > > [ 3708.716301] but task is already holding lock: > > [ 3708.716301] (&(&dentry->d_lock)->rlock/1){+.+...}, at: [] autofs4_expire_indirect+0xe0/0x4e0 [autofs4] > > [ 3708.716301] > > [ 3708.716301] other info that might help us debug this: > > [ 3708.716301] Possible unsafe locking scenario: > > [ 3708.716301] > > [ 3708.716301] CPU0 > > [ 3708.716301] ---- > > [ 3708.716301] lock(&(&dentry->d_lock)->rlock); > > [ 3708.716301] lock(&(&dentry->d_lock)->rlock); > > [ 3708.716301] > > [ 3708.716301] *** DEADLOCK *** > > [ 3708.716301] > > [ 3708.716301] May be due to missing lock nesting notation > > [ 3708.716301] > > [ 3708.716301] 2 locks held by automount/29215: > > [ 3708.716301] #0: (&(&sbi->lookup_lock)->rlock){+.+...}, at: [] autofs4_expire_indirect+0x91/0x4e0 [autofs4] > > [ 3708.716301] #1: (&(&dentry->d_lock)->rlock/1){+.+...}, at: [] autofs4_expire_indirect+0xe0/0x4e0 [autofs4] > > [ 3708.716301] > > [ 3708.716301] stack backtrace: > > [ 3708.716301] Pid: 29215, comm: automount Not tainted 3.0.8-vs2.3.1-dirty #6 > > [ 3708.716301] Call Trace: > > [ 3708.716301] [] __lock_acquire+0x1606/0x1b50 > > [ 3708.716301] [] ? autofs4_expire_indirect+0xe0/0x4e0 [autofs4] > > [ 3708.716301] [] ? lock_release_non_nested+0x14a/0x310 > > [ 3708.716301] [] ? autofs4_expire_indirect+0xe0/0x4e0 [autofs4] > > [ 3708.716301] [] ? autofs4_expire_indirect+0xe0/0x4e0 [autofs4] > > [ 3708.716301] [] lock_acquire+0x85/0x110 > > [ 3708.716301] [] ? autofs4_expire_indirect+0xe0/0x4e0 [autofs4] > > [ 3708.716301] [] ? autofs4_expire_indirect+0x2ed/0x4e0 [autofs4] > > [ 3708.716301] [] _raw_spin_lock_nested+0x2a/0x40 > > [ 3708.716301] [] ? autofs4_expire_indirect+0xe0/0x4e0 [autofs4] > > [ 3708.716301] [] ? _raw_spin_unlock+0x26/0x30 > > [ 3708.716301] [] ? might_fault+0x40/0x90 > > [ 3708.716301] [] autofs4_expire_indirect+0xe0/0x4e0 [autofs4] > > [ 3708.716301] [] autofs4_do_expire_multi+0xed/0x130 [autofs4] > > [ 3708.716301] [] ? autofs_dev_ioctl_askumount+0x30/0x30 [autofs4] > > [ 3708.716301] [] autofs_dev_ioctl_expire+0x1a/0x20 [autofs4] > > [ 3708.716301] [] _autofs_dev_ioctl+0x273/0x360 [autofs4] > > [ 3708.716301] [] autofs_dev_ioctl+0xe/0x20 [autofs4] > > [ 3708.716301] [] do_vfs_ioctl+0x96/0x560 > > [ 3708.716301] [] ? fget_light+0x99/0x130 > > [ 3708.716301] [] ? fget_light+0x37/0x130 > > [ 3708.716301] [] sys_ioctl+0x91/0xa0 > > [ 3708.716301] [] system_call_fastpath+0x16/0x1b > > Cheers,