Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752252AbaFCKed (ORCPT ); Tue, 3 Jun 2014 06:34:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:20051 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751201AbaFCKec (ORCPT ); Tue, 3 Jun 2014 06:34:32 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <1400838223-30844-1-git-send-email-miklos@szeredi.hu> <28592.1401382081@warthog.procyon.org.uk> <11446.1401420931@jrobl> <7184.1401439773@warthog.procyon.org.uk> <15839.1401786056@warthog.procyon.org.uk>

To: Miklos Szeredi Cc: dhowells@redhat.com, Sedat Dilek , "J. R. Okajima" , Al Viro , Linus Torvalds , linux-fsdevel , LKML , Christoph Hellwig , Andrew Morton , Robo Bot , Felix Fietkau , Neil Brown , Jordi Pujol , ezk@fsl.cs.sunysb.edu, "mszeredi@suse.cz" Subject: Re: Unionmount and overlayfs testsuite Date: Tue, 03 Jun 2014 11:33:54 +0100 Message-ID: <10013.1401791634@warthog.procyon.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Miklos Szeredi wrote: > Fix now pushed to overlayfs.v22/overlayfs.current. I ran my testscript, which leaves a clean set up and mounted overlay fs behind. I then ran: for ((i=100; i<=129; i++)); do mv /mnt/a/foo$i /mnt/a/bar$i; done for ((i=100; i<=129; i++)); do mv /mnt/a/dir$i /mnt/a/dir2$i; done leading to: ============================================= [ INFO: possible recursive locking detected ] 3.15.0-rc6-fsdevel+ #382 Tainted: G W --------------------------------------------- mv/27935 is trying to acquire lock: (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [] vfs_rmdir+0x59/0xe8 but task is already holding lock: (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [] ovl_clear_empty+0x175/0x1eb other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&sb->s_type->i_mutex_key#9); lock(&sb->s_type->i_mutex_key#9); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by mv/27935: #0: (sb_writers#15){.+.+.+}, at: [] mnt_want_write+0x1c/0x40 #1: (&sb->s_type->i_mutex_key#17/1){+.+.+.}, at: [] do_rmdir+0x9f/0x152 #2: (&sb->s_type->i_mutex_key#17){+.+.+.}, at: [] vfs_rmdir+0x59/0xe8 #3: (sb_writers#8){.+.+.+}, at: [] mnt_want_write+0x1c/0x40 #4: (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [] ovl_clear_empty+0x175/0x1eb stack backtrace: CPU: 1 PID: 27935 Comm: mv Tainted: G W 3.15.0-rc6-fsdevel+ #382 Hardware name: /DG965RY, BIOS MQ96510J.86A.0816.2006.0716.2308 07/16/2006 0000000000000000 ffff880038ac9af0 ffffffff8148b889 ffffffff81fda190 ffff880038ac9bb0 ffffffff81074b0e 0000000000000002 ffff88003823c890 0000000000000000 ffff880000000000 ffff880000000004 ffff880000000000 Call Trace: [] dump_stack+0x4d/0x66 [] __lock_acquire+0x75a/0x1861 [] lock_acquire+0x9c/0x112 [] ? vfs_rmdir+0x59/0xe8 [] mutex_lock_nested+0x60/0x2ff [] ? vfs_rmdir+0x59/0xe8 [] vfs_rmdir+0x59/0xe8 [] ovl_cleanup+0x1d/0x40 [] ovl_clear_empty+0x180/0x1eb [] ovl_check_empty_and_clear+0x41/0x5c [] ? creds_are_invalid+0x18/0x45 [] ovl_do_remove+0x17c/0x35e [] ovl_rmdir+0x11/0x13 [] vfs_rmdir+0x88/0xe8 [] do_rmdir+0xe6/0x152 [] ? __audit_syscall_entry+0xa1/0xc3 [] ? syscall_trace_enter+0x197/0x1eb [] SyS_unlinkat+0x16/0x29 [] tracesys+0xdd/0xe2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/