linux/fs/btrfs
Liu Bo 2a85d9cac1 Btrfs: fix possible deadlock in btrfs_cleanup_transaction
[13654.480669] ======================================================
[13654.480905] [ INFO: possible circular locking dependency detected ]
[13654.481003] 3.12.0+ #4 Tainted: G        W  O
[13654.481060] -------------------------------------------------------
[13654.481060] btrfs-transacti/9347 is trying to acquire lock:
[13654.481060]  (&(&root->ordered_extent_lock)->rlock){+.+...}, at: [<ffffffffa02d30a1>] btrfs_cleanup_transaction+0x271/0x570 [btrfs]
[13654.481060] but task is already holding lock:
[13654.481060]  (&(&fs_info->ordered_root_lock)->rlock){+.+...}, at: [<ffffffffa02d3015>] btrfs_cleanup_transaction+0x1e5/0x570 [btrfs]
[13654.481060] which lock already depends on the new lock.

[13654.481060] the existing dependency chain (in reverse order) is:
[13654.481060] -> #1 (&(&fs_info->ordered_root_lock)->rlock){+.+...}:
[13654.481060]        [<ffffffff810c4103>] lock_acquire+0x93/0x130
[13654.481060]        [<ffffffff81689991>] _raw_spin_lock+0x41/0x50
[13654.481060]        [<ffffffffa02f011b>] __btrfs_add_ordered_extent+0x39b/0x450 [btrfs]
[13654.481060]        [<ffffffffa02f0202>] btrfs_add_ordered_extent+0x32/0x40 [btrfs]
[13654.481060]        [<ffffffffa02df6aa>] run_delalloc_nocow+0x78a/0x9d0 [btrfs]
[13654.481060]        [<ffffffffa02dfc0d>] run_delalloc_range+0x31d/0x390 [btrfs]
[13654.481060]        [<ffffffffa02f7c00>] __extent_writepage+0x310/0x780 [btrfs]
[13654.481060]        [<ffffffffa02f830a>] extent_write_cache_pages.isra.29.constprop.48+0x29a/0x410 [btrfs]
[13654.481060]        [<ffffffffa02f879d>] extent_writepages+0x4d/0x70 [btrfs]
[13654.481060]        [<ffffffffa02d9f68>] btrfs_writepages+0x28/0x30 [btrfs]
[13654.481060]        [<ffffffff8114be91>] do_writepages+0x21/0x50
[13654.481060]        [<ffffffff81140d49>] __filemap_fdatawrite_range+0x59/0x60
[13654.481060]        [<ffffffff81140e13>] filemap_fdatawrite_range+0x13/0x20
[13654.481060]        [<ffffffffa02f1db9>] btrfs_wait_ordered_range+0x49/0x140 [btrfs]
[13654.481060]        [<ffffffffa0318fe2>] __btrfs_write_out_cache+0x682/0x8b0 [btrfs]
[13654.481060]        [<ffffffffa031952d>] btrfs_write_out_cache+0x8d/0xe0 [btrfs]
[13654.481060]        [<ffffffffa02c7083>] btrfs_write_dirty_block_groups+0x593/0x680 [btrfs]
[13654.481060]        [<ffffffffa0345307>] commit_cowonly_roots+0x14b/0x20d [btrfs]
[13654.481060]        [<ffffffffa02d7c1a>] btrfs_commit_transaction+0x43a/0x9d0 [btrfs]
[13654.481060]        [<ffffffffa030061a>] btrfs_create_uuid_tree+0x5a/0x100 [btrfs]
[13654.481060]        [<ffffffffa02d5a8a>] open_ctree+0x21da/0x2210 [btrfs]
[13654.481060]        [<ffffffffa02ab6fe>] btrfs_mount+0x68e/0x870 [btrfs]
[13654.481060]        [<ffffffff811b2409>] mount_fs+0x39/0x1b0
[13654.481060]        [<ffffffff811cd653>] vfs_kern_mount+0x63/0xf0
[13654.481060]        [<ffffffff811cfcce>] do_mount+0x23e/0xa90
[13654.481060]        [<ffffffff811d05a3>] SyS_mount+0x83/0xc0
[13654.481060]        [<ffffffff81692b52>] system_call_fastpath+0x16/0x1b
[13654.481060] -> #0 (&(&root->ordered_extent_lock)->rlock){+.+...}:
[13654.481060]        [<ffffffff810c340a>] __lock_acquire+0x150a/0x1a70
[13654.481060]        [<ffffffff810c4103>] lock_acquire+0x93/0x130
[13654.481060]        [<ffffffff81689991>] _raw_spin_lock+0x41/0x50
[13654.481060]        [<ffffffffa02d30a1>] btrfs_cleanup_transaction+0x271/0x570 [btrfs]
[13654.481060]        [<ffffffffa02d35ce>] transaction_kthread+0x22e/0x270 [btrfs]
[13654.481060]        [<ffffffff81079efa>] kthread+0xea/0xf0
[13654.481060]        [<ffffffff81692aac>] ret_from_fork+0x7c/0xb0
[13654.481060] other info that might help us debug this:

[13654.481060]  Possible unsafe locking scenario:

[13654.481060]        CPU0                    CPU1
[13654.481060]        ----                    ----
[13654.481060]   lock(&(&fs_info->ordered_root_lock)->rlock);
[13654.481060]				 lock(&(&root->ordered_extent_lock)->rlock);
[13654.481060]				 lock(&(&fs_info->ordered_root_lock)->rlock);
[13654.481060]   lock(&(&root->ordered_extent_lock)->rlock);
[13654.481060]
 *** DEADLOCK ***
[...]

======================================================

btrfs_destroy_all_ordered_extents()
gets &fs_info->ordered_root_lock __BEFORE__ acquiring &root->ordered_extent_lock,
while btrfs_[add,remove]_ordered_extent()
acquires &fs_info->ordered_root_lock __AFTER__ getting &root->ordered_extent_lock.

This patch fixes the above problem.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:37 -04:00
..
tests Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
acl.c btrfs: remove dead code 2014-01-28 13:19:50 -08:00
async-thread.c btrfs: always choose work from prio_head first 2014-03-10 15:16:36 -04:00
async-thread.h Btrfs: eliminate races in worker stopping code 2013-10-04 16:02:13 -04:00
backref.c Btrfs: switch to btrfs_previous_extent_item() 2014-03-10 15:15:54 -04:00
backref.h Btrfs: allocate prelim_ref with a slab allocater 2013-09-01 08:16:27 -04:00
btrfs_inode.h Btrfs: add support for inode properties 2014-01-28 13:20:24 -08:00
check-integrity.c Btrfs: use btrfs_crc32c everywhere instead of libcrc32c 2014-02-03 09:01:27 -08:00
check-integrity.h block: submit_bio_wait() conversions 2013-11-24 16:33:41 -07:00
compression.c Btrfs: fix data corruption when reading/updating compressed extents 2014-02-08 17:57:15 -08:00
compression.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
ctree.c Btrfs: fix btrfs_search_slot_for_read backwards iteration 2014-01-29 07:06:28 -08:00
ctree.h Btrfs: fix use-after-free in the finishing procedure of the device replace 2014-03-10 15:15:39 -04:00
delayed-inode.c Btrfs: introduce the delayed inode ref deletion for the single link inode 2014-01-28 13:20:09 -08:00
delayed-inode.h Btrfs: introduce the delayed inode ref deletion for the single link inode 2014-01-28 13:20:09 -08:00
delayed-ref.c Btrfs: attach delayed ref updates to delayed ref heads 2014-01-28 13:20:25 -08:00
delayed-ref.h Btrfs: attach delayed ref updates to delayed ref heads 2014-01-28 13:20:25 -08:00
dev-replace.c Btrfs: fix use-after-free in the finishing procedure of the device replace 2014-03-10 15:15:39 -04:00
dev-replace.h Btrfs: add new sources for device replace code 2012-12-12 17:15:41 -05:00
dir-item.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
disk-io.c Btrfs: fix possible deadlock in btrfs_cleanup_transaction 2014-03-10 15:16:37 -04:00
disk-io.h Btrfs: add a sanity test for btrfs_split_item 2013-11-11 21:51:02 -05:00
export.c btrfs: remove fs/btrfs/compat.h 2013-11-11 22:03:19 -05:00
export.h
extent_io.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
extent_io.h Btrfs: move the extent buffer radix tree into the fs_info 2014-01-28 13:19:55 -08:00
extent_map.c Btrfs: fix extent_map block_len after merging 2014-01-28 13:19:51 -08:00
extent_map.h btrfs: Enclose macros with complex values within parenthesis 2013-11-11 22:12:06 -05:00
extent-tree.c Btrfs: don't loop forever if we can't run because of the tree mod log 2014-02-08 17:57:15 -08:00
file-item.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
file.c Btrfs: faster/more efficient insertion of file extent items 2014-03-10 15:16:37 -04:00
free-space-cache.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
free-space-cache.h Btrfs: remove path arg from btrfs_truncate_free_space_cache 2013-11-11 21:51:33 -05:00
hash.c Btrfs: fix btrfs boot when compiled as built-in 2014-01-28 13:20:31 -08:00
hash.h Btrfs: fix btrfs boot when compiled as built-in 2014-01-28 13:20:31 -08:00
inode-item.c btrfs: cleanup: removed unused 'btrfs_get_inode_ref_index' 2014-01-28 13:19:39 -08:00
inode-map.c btrfs: Use WARN_ON()'s return value in place of WARN_ON(1) 2013-11-11 22:11:53 -05:00
inode-map.h Btrfs: Support reading/writing on disk free ino cache 2011-04-25 16:46:11 +08:00
inode.c Btrfs: skip readonly root for snapshot-aware defragment 2014-03-10 15:16:34 -04:00
ioctl.c btrfs: Fix 32/64-bit problem with BTRFS_SET_RECEIVED_SUBVOL ioctl 2014-03-10 15:15:40 -04:00
Kconfig Btrfs: fix btrfs boot when compiled as built-in 2014-01-28 13:20:31 -08:00
locking.c btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
locking.h Btrfs: remove btrfs_try_spin_lock 2013-03-14 14:57:10 -04:00
lzo.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
Makefile Btrfs: fix btrfs boot when compiled as built-in 2014-01-28 13:20:31 -08:00
math.h Btrfs: cleanup duplicated division functions 2012-12-11 13:31:30 -05:00
ordered-data.c Btrfs: don't mix the ordered extents of all files together during logging the inodes 2014-03-10 15:15:36 -04:00
ordered-data.h Btrfs: don't mix the ordered extents of all files together during logging the inodes 2014-03-10 15:15:36 -04:00
orphan.c btrfs: expand btrfs_find_item() to include find_orphan_item functionality 2014-01-28 13:19:37 -08:00
print-tree.c Btrfs: don't use ram_bytes for uncompressed inline items 2014-01-29 07:06:29 -08:00
print-tree.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
props.c Btrfs: add support for inode properties 2014-01-28 13:20:24 -08:00
props.h Btrfs: add support for inode properties 2014-01-28 13:20:24 -08:00
qgroup.c Btrfs: fix qgroup rescan to work with skinny metadata 2014-01-28 13:20:27 -08:00
raid56.c btrfs: remove fs/btrfs/compat.h 2013-11-11 22:03:19 -05:00
raid56.h Btrfs: RAID5 and RAID6 2013-02-01 14:24:23 -05:00
rcu-string.h Btrfs: use rcu to protect device->name 2012-06-14 21:29:16 -04:00
reada.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
relocation.c Btrfs: fix an oops when we fail to relocate tree blocks 2014-01-28 13:20:14 -08:00
root-tree.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
scrub.c Btrfs: fix to search previous metadata extent item since skinny metadata 2014-01-28 13:20:33 -08:00
send.c Revert "Btrfs: remove transaction from btrfs send" 2014-03-10 15:16:35 -04:00
send.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
struct-funcs.c Btrfs: rewrite BTRFS_SETGET_FUNCS 2012-07-23 16:28:06 -04:00
super.c Btrfs: unset DCACHE_DISCONNECTED when mounting default subvol 2014-02-14 13:44:32 -08:00
sysfs.c btrfs: add simple debugfs interface 2014-03-10 15:15:51 -04:00
sysfs.h btrfs: add simple debugfs interface 2014-03-10 15:15:51 -04:00
transaction.c btrfs: Add noinode_cache mount option 2014-01-28 13:20:33 -08:00
transaction.h Btrfs: make fsync latency less sucky 2014-01-28 13:20:25 -08:00
tree-defrag.c Btrfs: cleanup dead code of defragment 2013-11-11 21:59:45 -05:00
tree-log.c Btrfs: don't mix the ordered extents of all files together during logging the inodes 2014-03-10 15:15:36 -04:00
tree-log.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
ulist.c Btrfs: do not export ulist functions 2014-01-29 07:06:27 -08:00
ulist.h Btrfs: do not export ulist functions 2014-01-29 07:06:27 -08:00
uuid-tree.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
volumes.c Btrfs: fix use-after-free in the finishing procedure of the device replace 2014-03-10 15:15:39 -04:00
volumes.h Btrfs: fix use-after-free in the finishing procedure of the device replace 2014-03-10 15:15:39 -04:00
xattr.c Btrfs: add support for inode properties 2014-01-28 13:20:24 -08:00
xattr.h fs/vfs/security: pass last path component to LSM on inode creation 2011-02-01 11:12:29 -05:00
zlib.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00