lkml.org 
[lkml]   [2010]   [Oct]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[051/103] reiserfs: fix dependency inversion between inode and reiserfs mutexes
2.6.35-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Frederic Weisbecker <fweisbec@gmail.com>

commit 3f259d092c7a2fdf217823e8f1838530adb0cdb0 upstream.

The reiserfs mutex already depends on the inode mutex, so we can't lock
the inode mutex in reiserfs_unpack() without using the safe locking API,
because reiserfs_unpack() is always called with the reiserfs mutex locked.

This fixes:

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.35c #13
-------------------------------------------------------
lilo/1606 is trying to acquire lock:
(&sb->s_type->i_mutex_key#8){+.+.+.}, at: [<d0329450>] reiserfs_unpack+0x60/0x110 [reiserfs]

but task is already holding lock:
(&REISERFS_SB(s)->lock){+.+.+.}, at: [<d032a268>] reiserfs_write_lock+0x28/0x40 [reiserfs]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&REISERFS_SB(s)->lock){+.+.+.}:
[<c1056347>] lock_acquire+0x67/0x80
[<c12f083d>] __mutex_lock_common+0x4d/0x410
[<c12f0c58>] mutex_lock_nested+0x18/0x20
[<d032a268>] reiserfs_write_lock+0x28/0x40 [reiserfs]
[<d0329e9a>] reiserfs_lookup_privroot+0x2a/0x90 [reiserfs]
[<d0316b81>] reiserfs_fill_super+0x941/0xe60 [reiserfs]
[<c10b7d17>] get_sb_bdev+0x117/0x170
[<d0313e21>] get_super_block+0x21/0x30 [reiserfs]
[<c10b74ba>] vfs_kern_mount+0x6a/0x1b0
[<c10b7659>] do_kern_mount+0x39/0xe0
[<c10cebe0>] do_mount+0x340/0x790
[<c10cf0b4>] sys_mount+0x84/0xb0
[<c12f25cd>] syscall_call+0x7/0xb

-> #0 (&sb->s_type->i_mutex_key#8){+.+.+.}:
[<c1056186>] __lock_acquire+0x1026/0x1180
[<c1056347>] lock_acquire+0x67/0x80
[<c12f083d>] __mutex_lock_common+0x4d/0x410
[<c12f0c58>] mutex_lock_nested+0x18/0x20
[<d0329450>] reiserfs_unpack+0x60/0x110 [reiserfs]
[<d0329772>] reiserfs_ioctl+0x272/0x320 [reiserfs]
[<c10c3228>] vfs_ioctl+0x28/0xa0
[<c10c3c5d>] do_vfs_ioctl+0x32d/0x5c0
[<c10c3f53>] sys_ioctl+0x63/0x70
[<c12f25cd>] syscall_call+0x7/0xb

other info that might help us debug this:

1 lock held by lilo/1606:
#0: (&REISERFS_SB(s)->lock){+.+.+.}, at: [<d032a268>] reiserfs_write_lock+0x28/0x40 [reiserfs]

stack backtrace:
Pid: 1606, comm: lilo Not tainted 2.6.35c #13
Call Trace:
[<c1056186>] __lock_acquire+0x1026/0x1180
[<c1056347>] lock_acquire+0x67/0x80
[<c12f083d>] __mutex_lock_common+0x4d/0x410
[<c12f0c58>] mutex_lock_nested+0x18/0x20
[<d0329450>] reiserfs_unpack+0x60/0x110 [reiserfs]
[<d0329772>] reiserfs_ioctl+0x272/0x320 [reiserfs]
[<c10c3228>] vfs_ioctl+0x28/0xa0
[<c10c3c5d>] do_vfs_ioctl+0x32d/0x5c0
[<c10c3f53>] sys_ioctl+0x63/0x70
[<c12f25cd>] syscall_call+0x7/0xb

Reported-by: Jarek Poplawski <jarkao2@gmail.com>
Tested-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
fs/reiserfs/ioctl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/reiserfs/ioctl.c
+++ b/fs/reiserfs/ioctl.c
@@ -188,7 +188,7 @@ int reiserfs_unpack(struct inode *inode,
/* we need to make sure nobody is changing the file size beneath
** us
*/
- mutex_lock(&inode->i_mutex);
+ reiserfs_mutex_lock_safe(&inode->i_mutex, inode->i_sb);
reiserfs_write_lock(inode->i_sb);

write_from = inode->i_size & (blocksize - 1);



\
 
 \ /
  Last update: 2010-10-22 21:13    [W:0.199 / U:1.008 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site