The patch titled
reiserfs: fix unwanted reiserfs lock recursion
has been added to the -mm tree. Its filename is
reiserfs-fix-unwanted-reiserfs-lock-recursion.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: reiserfs: fix unwanted reiserfs lock recursion
From: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Prevent from recursively locking the reiserfs lock in reiserfs_unpack()
because we may call journal_begin() that requires the lock to be taken
only once, otherwise it won't be able to release the lock while taking
other mutexes, ending up in inverted dependencies between the journal
mutex and the reiserfs lock for example.
This fixes:
[ 67.110273] =======================================================
[ 67.110313] [ INFO: possible circular locking dependency detected ]
[ 67.110313] 2.6.35.4.4a #3
[ 67.110313] -------------------------------------------------------
[ 67.110313] lilo/1620 is trying to acquire lock:
[ 67.110313] (&journal->j_mutex){+.+...}, at: [<d0325bff>] do_journal_begin_r+0x7f/0x340 [reiserfs]
[ 67.110313]
[ 67.110313] but task is already holding lock:
[ 67.110313] (&REISERFS_SB(s)->lock){+.+.+.}, at: [<d032a278>] reiserfs_write_lock+0x28/0x40 [reiserfs]
[ 67.110313]
[ 67.110313] which lock already depends on the new lock.
[ 67.110313]
[ 67.110313]
[ 67.110313] the existing dependency chain (in reverse order) is:
[ 67.110313]
[ 67.110313] -> #1 (&REISERFS_SB(s)->lock){+.+.+.}:
[ 67.110313] [<c10562b7>] lock_acquire+0x67/0x80
[ 67.110313] [<c12facad>] __mutex_lock_common+0x4d/0x410
[ 67.110313] [<c12fb0c8>] mutex_lock_nested+0x18/0x20
[ 67.110313] [<d032a278>] reiserfs_write_lock+0x28/0x40 [reiserfs]
[ 67.110313] [<d0325c06>] do_journal_begin_r+0x86/0x340 [reiserfs]
[ 67.110313] [<d0325f77>] journal_begin+0x77/0x140 [reiserfs]
[ 67.110313] [<d0315be4>] reiserfs_remount+0x224/0x530 [reiserfs]
[ 67.110313] [<c10b6a20>] do_remount_sb+0x60/0x110
[ 67.110313] [<c10cee25>] do_mount+0x625/0x790
[ 67.110313] [<c10cf014>] sys_mount+0x84/0xb0
[ 67.110313] [<c12fca3d>] syscall_call+0x7/0xb
[ 67.110313]
[ 67.110313] -> #0 (&journal->j_mutex){+.+...}:
[ 67.110313] [<c10560f6>] __lock_acquire+0x1026/0x1180
[ 67.110313] [<c10562b7>] lock_acquire+0x67/0x80
[ 67.110313] [<c12facad>] __mutex_lock_common+0x4d/0x410
[ 67.110313] [<c12fb0c8>] mutex_lock_nested+0x18/0x20
[ 67.110313] [<d0325bff>] do_journal_begin_r+0x7f/0x340 [reiserfs]
[ 67.110313] [<d0325f77>] journal_begin+0x77/0x140 [reiserfs]
[ 67.110313] [<d0326271>] reiserfs_persistent_transaction+0x41/0x90 [reiserfs]
[ 67.110313] [<d030d06c>] reiserfs_get_block+0x22c/0x1530 [reiserfs]
[ 67.110313] [<c10db9db>] __block_prepare_write+0x1bb/0x3a0
[ 67.110313] [<c10dbbe6>] block_prepare_write+0x26/0x40
[ 67.110313] [<d030b738>] reiserfs_prepare_write+0x88/0x170 [reiserfs]
[ 67.110313] [<d03294d6>] reiserfs_unpack+0xe6/0x120 [reiserfs]
[ 67.110313] [<d0329782>] reiserfs_ioctl+0x272/0x320 [reiserfs]
[ 67.110313] [<c10c3188>] vfs_ioctl+0x28/0xa0
[ 67.110313] [<c10c3bbd>] do_vfs_ioctl+0x32d/0x5c0
[ 67.110313] [<c10c3eb3>] sys_ioctl+0x63/0x70
[ 67.110313] [<c12fca3d>] syscall_call+0x7/0xb
[ 67.110313]
[ 67.110313] other info that might help us debug this:
[ 67.110313]
[ 67.110313] 2 locks held by lilo/1620:
[ 67.110313] #0: (&sb->s_type->i_mutex_key#8){+.+.+.}, at: [<d032945a>] reiserfs_unpack+0x6a/0x120 [reiserfs]
[ 67.110313] #1: (&REISERFS_SB(s)->lock){+.+.+.}, at: [<d032a278>] reiserfs_write_lock+0x28/0x40 [reiserfs]
[ 67.110313]
[ 67.110313] stack backtrace:
[ 67.110313] Pid: 1620, comm: lilo Not tainted 2.6.35.4.4a #3
[ 67.110313] Call Trace:
[ 67.110313] [<c12f9aba>] ? printk+0x18/0x1e
[ 67.110313] [<c1054182>] print_circular_bug+0xd2/0xe0
[ 67.110313] [<c10560f6>] __lock_acquire+0x1026/0x1180
[ 67.110313] [<c10562b7>] lock_acquire+0x67/0x80
[ 67.110313] [<d0325bff>] ? do_journal_begin_r+0x7f/0x340 [reiserfs]
[ 67.110313] [<c12facad>] __mutex_lock_common+0x4d/0x410
[ 67.110313] [<d0325bff>] ? do_journal_begin_r+0x7f/0x340 [reiserfs]
[ 67.110313] [<c1055275>] ? __lock_acquire+0x1a5/0x1180
[ 67.110313] [<c10897ae>] ? mempool_alloc_slab+0xe/0x10
[ 67.110313] [<c12fb0c8>] mutex_lock_nested+0x18/0x20
[ 67.110313] [<d0325bff>] ? do_journal_begin_r+0x7f/0x340 [reiserfs]
[ 67.110313] [<d0325bff>] do_journal_begin_r+0x7f/0x340 [reiserfs]
[ 67.110313] [<c1054bd2>] ? mark_held_locks+0x62/0x80
[ 67.110313] [<c10b163d>] ? kmem_cache_alloc+0x7d/0xb0
[ 67.110313] [<c1054e5c>] ? trace_hardirqs_on_caller+0x11c/0x160
[ 67.110313] [<d0325f77>] journal_begin+0x77/0x140 [reiserfs]
[ 67.110313] [<d0326262>] ? reiserfs_persistent_transaction+0x32/0x90 [reiserfs]
[ 67.110313] [<d0326271>] reiserfs_persistent_transaction+0x41/0x90 [reiserfs]
[ 67.110313] [<d030d06c>] reiserfs_get_block+0x22c/0x1530 [reiserfs]
[ 67.110313] [<c1055275>] ? __lock_acquire+0x1a5/0x1180
[ 67.110313] [<c12fc672>] ? _raw_spin_unlock_irq+0x22/0x50
[ 67.110313] [<c10b163d>] ? kmem_cache_alloc+0x7d/0xb0
[ 67.110313] [<c1054e5c>] ? trace_hardirqs_on_caller+0x11c/0x160
[ 67.110313] [<c102789b>] ? sub_preempt_count+0x7b/0xb0
[ 67.110313] [<c12fc457>] ? _raw_spin_unlock+0x27/0x40
[ 67.110313] [<c10db9db>] __block_prepare_write+0x1bb/0x3a0
[ 67.110313] [<c10dbbe6>] block_prepare_write+0x26/0x40
[ 67.110313] [<d030ce40>] ? reiserfs_get_block+0x0/0x1530 [reiserfs]
[ 67.110313] [<d030b738>] reiserfs_prepare_write+0x88/0x170 [reiserfs]
[ 67.110313] [<d030ce40>] ? reiserfs_get_block+0x0/0x1530 [reiserfs]
[ 67.110313] [<d03294d6>] reiserfs_unpack+0xe6/0x120 [reiserfs]
[ 67.110313] [<d0329782>] reiserfs_ioctl+0x272/0x320 [reiserfs]
[ 67.110313] [<d0329510>] ? reiserfs_ioctl+0x0/0x320 [reiserfs]
[ 67.110313] [<c10c3188>] vfs_ioctl+0x28/0xa0
[ 67.110313] [<c10c3bbd>] do_vfs_ioctl+0x32d/0x5c0
[ 67.110313] [<c109a228>] ? might_fault+0x88/0x90
[ 67.110313] [<c109a1e2>] ? might_fault+0x42/0x90
[ 67.110313] [<c10b6588>] ? fget_light+0xf8/0x2f0
[ 67.110313] [<c10c3eb3>] sys_ioctl+0x63/0x70
[ 67.110313] [<c12fca3d>] syscall_call+0x7/0xb
[ 67.110313] [<c12f007b>] ? cookie_v6_check+0x44b/0x630
Reported-by: Jarek Poplawski <jarkao2@xxxxxxxxx>
Tested-by: Jarek Poplawski <jarkao2@xxxxxxxxx>
Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Jeff Mahoney <jeffm@xxxxxxxx>
Cc: All since 2.6.32 <stable@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/reiserfs/ioctl.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff -puN fs/reiserfs/ioctl.c~reiserfs-fix-unwanted-reiserfs-lock-recursion fs/reiserfs/ioctl.c
--- a/fs/reiserfs/ioctl.c~reiserfs-fix-unwanted-reiserfs-lock-recursion
+++ a/fs/reiserfs/ioctl.c
@@ -170,6 +170,7 @@ int reiserfs_prepare_write(struct file *
int reiserfs_unpack(struct inode *inode, struct file *filp)
{
int retval = 0;
+ int depth;
int index;
struct page *page;
struct address_space *mapping;
@@ -189,7 +190,7 @@ int reiserfs_unpack(struct inode *inode,
** us
*/
reiserfs_mutex_lock_safe(&inode->i_mutex, inode->i_sb);
- reiserfs_write_lock(inode->i_sb);
+ depth = reiserfs_write_lock_once(inode->i_sb);
write_from = inode->i_size & (blocksize - 1);
/* if we are on a block boundary, we are already unpacked. */
@@ -224,6 +225,6 @@ int reiserfs_unpack(struct inode *inode,
out:
mutex_unlock(&inode->i_mutex);
- reiserfs_write_unlock(inode->i_sb);
+ reiserfs_write_unlock_once(inode->i_sb, depth);
return retval;
}
_
Patches currently in -mm which might be from fweisbec@xxxxxxxxx are
origin.patch
linux-next.patch
reiserfs-fix-dependency-inversion-between-inode-and-reiserfs-mutexes.patch
reiserfs-fix-unwanted-reiserfs-lock-recursion.patch
autofs-only-declare-function-when-config_compat-is-defined.patch
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