From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Beregalov Subject: Re: [PATCH 0/4] kill-the-bkl/reiserfs: fix some lock dependency inversions Date: Thu, 27 Aug 2009 00:13:30 +0400 Message-ID: <20090826201330.GA18761@orion> References: <1251167570-5233-1-git-send-email-fweisbec@gmail.com> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:date:from:to:cc:subject :message-id:references:mime-version:content-type:content-disposition :in-reply-to:user-agent; bh=lVoA97HlahL8Z3QNeEWeFG3H+qWKRy9K8WRt6qY8biE=; b=bO0WHImriBt9XdFeQiTrH4wanzRpGKL6fe1BzNlhcJQHB32xDGlfWtPd1UL6zvFUg2 l+3FFFDfLuPvQVPClYZhZoSVQihB3yO+ky/lCcr7G36dbURIKcyLFY+9iVEeYGaxIfM8 9O8f4pQOpW8wNGP/vgkl8cQJJfI5RTxDH0i60= Content-Disposition: inline In-Reply-To: <1251167570-5233-1-git-send-email-fweisbec@gmail.com> Sender: reiserfs-devel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Frederic Weisbecker Cc: LKML , Reiserfs On Tue, Aug 25, 2009 at 04:32:46AM +0200, Frederic Weisbecker wrote: > Hi, > > This small set fixes some lock dependency inversions found in reiserfs > xattr and mmap paths. > I guess there are still some of them that I'll have to hunt, especially one > reported by Laurent Riffard and another one introduced by the reiserfs_readdir > path optimization (though I'm not sure about the latter, I have yet to find a > way to reproduce it properly). > > As usual, these patches can be found at: > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing.git \ > reiserfs/kill-bkl Hi, possible circular locking dependency detected Is it false positive? REISERFS (device sda1): found reiserfs format "3.6" with standard journal REISERFS (device sda1): using ordered data mode REISERFS (device sda1): journal params: device sda1, size 8192, journal first block 18, max trans len 1024, max batch 900, max commit age 30, max trans age 30 REISERFS (device sda1): checking transaction log (sda1) REISERFS debug (device sda1): journal-1153: found in header: first_unflushed_offset 6766, last_flushed_trans_id 1836992 REISERFS debug (device sda1): journal-1206: Starting replay from offset 7889824857987694, trans_id 18 REISERFS debug (device sda1): journal-1299: Setting newest_mount_id to 229 REISERFS (device sda1): Using r5 hash to sort names VFS: Mounted root (reiserfs filesystem) readonly on device 8:1. ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.31-rc7-00135-g9399a4c #5 ------------------------------------------------------- init.sh/599 is trying to acquire lock: (&mm->mmap_sem){++++++}, at: [] might_fault+0x46/0xa0 but task is already holding lock: (&REISERFS_SB(s)->lock){+.+.+.}, at: [] reiserfs_write_lock+0x1e/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&REISERFS_SB(s)->lock){+.+.+.}: [] __lock_acquire+0xd28/0x1390 [] lock_acquire+0x6f/0x90 [] __mutex_lock_common+0x46/0x310 [] mutex_lock_nested+0x38/0x40 [] reiserfs_write_lock_once+0x1e/0x40 [] reiserfs_get_block+0x5c/0x1440 [] do_mpage_readpage+0x120/0x4b0 [] mpage_readpages+0x9f/0xe0 [] reiserfs_readpages+0x19/0x20 [] __do_page_cache_readahead+0x195/0x210 [] ra_submit+0x21/0x30 [] filemap_fault+0x2e9/0x380 [] __do_fault+0x38/0x3b0 [] handle_mm_fault+0xcd/0x550 [] do_page_fault+0xf3/0x240 [] error_code+0x63/0x68 [] padzero+0x24/0x40 [] load_elf_binary+0x632/0x1480 [] search_binary_handler+0x8a/0x270 [] do_execve+0x215/0x2a0 [] sys_execve+0x28/0x60 [] syscall_call+0x7/0xb [] 0xffffffff -> #0 (&mm->mmap_sem){++++++}: [] __lock_acquire+0xda9/0x1390 [] lock_acquire+0x6f/0x90 [] might_fault+0x77/0xa0 [] copy_to_user+0x36/0x130 [] filldir64+0xa9/0xf0 [] reiserfs_readdir_dentry+0x4a1/0x7b0 [] reiserfs_readdir+0x17/0x20 [] vfs_readdir+0x85/0xa0 [] sys_getdents64+0x64/0xb0 [] sysenter_do_call+0x12/0x36 [] 0xffffffff other info that might help us debug this: 2 locks held by init.sh/599: #0: (&sb->s_type->i_mutex_key#4){+.+.+.}, at: [] vfs_readdir+0x52/0xa0 #1: (&REISERFS_SB(s)->lock){+.+.+.}, at: [] reiserfs_write_lock+0x1e/0x30 stack backtrace: Pid: 599, comm: init.sh Not tainted 2.6.31-rc7-00135-g9399a4c #5 Call Trace: [] ? printk+0x18/0x1e [] print_circular_bug_tail+0x8d/0xd0 [] __lock_acquire+0xda9/0x1390 [] lock_acquire+0x6f/0x90 [] ? might_fault+0x46/0xa0 [] might_fault+0x77/0xa0 [] ? might_fault+0x46/0xa0 [] copy_to_user+0x36/0x130 [] filldir64+0xa9/0xf0 [] ? reiserfs_write_lock+0x1e/0x30 [] reiserfs_readdir_dentry+0x4a1/0x7b0 [] ? filldir64+0x0/0xf0 [] ? __lock_acquire+0x463/0x1390 [] ? trace_hardirqs_on_caller+0x7e/0x170 [] ? filldir64+0x0/0xf0 [] ? __mutex_lock_common+0x203/0x310 [] ? filldir64+0x0/0xf0 [] reiserfs_readdir+0x17/0x20 [] vfs_readdir+0x85/0xa0 [] sys_getdents64+0x64/0xb0 [] sysenter_do_call+0x12/0x36