linux/fs/btrfs
Filipe Manana b050f9f6dd Btrfs: fix qgroups sanity test crash or hang
Often when running the qgroups sanity test, a crash or a hang happened.
This is because the extent buffer the test uses for the root node doesn't
have an header level explicitly set, making it have a random level value.
This is a problem when it's not zero for the btrfs_search_slot() calls
the test ends up doing, resulting in crashes or hangs such as the following:

[ 6454.127192] Btrfs loaded, debug=on, assert=on, integrity-checker=on
(...)
[ 6454.127760] BTRFS: selftest: Running qgroup tests
[ 6454.127964] BTRFS: selftest: Running test_test_no_shared_qgroup
[ 6454.127966] BTRFS: selftest: Qgroup basic add
[ 6480.152005] BUG: soft lockup - CPU#0 stuck for 23s! [modprobe:5383]
[ 6480.152005] Modules linked in: btrfs(+) xor raid6_pq binfmt_misc nfsd auth_rpcgss oid_registry nfs_acl nfs lockd fscache sunrpc i2c_piix4 i2c_core pcspkr evbug psmouse serio_raw e1000 [last unloaded: btrfs]
[ 6480.152005] irq event stamp: 188448
[ 6480.152005] hardirqs last  enabled at (188447): [<ffffffff8168ef5c>] restore_args+0x0/0x30
[ 6480.152005] hardirqs last disabled at (188448): [<ffffffff81698e6a>] apic_timer_interrupt+0x6a/0x80
[ 6480.152005] softirqs last  enabled at (188446): [<ffffffff810516cf>] __do_softirq+0x1cf/0x450
[ 6480.152005] softirqs last disabled at (188441): [<ffffffff81051c25>] irq_exit+0xb5/0xc0
[ 6480.152005] CPU: 0 PID: 5383 Comm: modprobe Not tainted 3.15.0-rc8-fdm-btrfs-next-33+ #4
[ 6480.152005] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 6480.152005] task: ffff8802146125a0 ti: ffff8800d0d00000 task.ti: ffff8800d0d00000
[ 6480.152005] RIP: 0010:[<ffffffff81349a63>]  [<ffffffff81349a63>] __write_lock_failed+0x13/0x20
[ 6480.152005] RSP: 0018:ffff8800d0d038e8  EFLAGS: 00000287
[ 6480.152005] RAX: 0000000000000000 RBX: ffffffff8168ef5c RCX: 000005deb8525852
[ 6480.152005] RDX: 0000000000000000 RSI: 0000000000001d45 RDI: ffff8802105000b8
[ 6480.152005] RBP: ffff8800d0d038e8 R08: fffffe12710f63db R09: ffffffffa03196fb
[ 6480.152005] R10: ffff8802146125a0 R11: ffff880214612e28 R12: ffff8800d0d03858
[ 6480.152005] R13: 0000000000000000 R14: ffff8800d0d00000 R15: ffff8802146125a0
[ 6480.152005] FS:  00007f14ff804700(0000) GS:ffff880215e00000(0000) knlGS:0000000000000000
[ 6480.152005] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 6480.152005] CR2: 00007fff4df0dac8 CR3: 00000000d1796000 CR4: 00000000000006f0
[ 6480.152005] Stack:
[ 6480.152005]  ffff8800d0d03908 ffffffff810ae967 0000000000000001 ffff8802105000b8
[ 6480.152005]  ffff8800d0d03938 ffffffff8168e57e ffffffffa0319c16 0000000000000007
[ 6480.152005]  ffff880210500000 ffff880210500100 ffff8800d0d039b8 ffffffffa0319c16
[ 6480.152005] Call Trace:
[ 6480.152005]  [<ffffffff810ae967>] do_raw_write_lock+0x47/0xa0
[ 6480.152005]  [<ffffffff8168e57e>] _raw_write_lock+0x5e/0x80
[ 6480.152005]  [<ffffffffa0319c16>] ? btrfs_tree_lock+0x116/0x270 [btrfs]
[ 6480.152005]  [<ffffffffa0319c16>] btrfs_tree_lock+0x116/0x270 [btrfs]
[ 6480.152005]  [<ffffffffa02b2acb>] btrfs_lock_root_node+0x3b/0x50 [btrfs]
[ 6480.152005]  [<ffffffffa02b81a6>] btrfs_search_slot+0x916/0xa20 [btrfs]
[ 6480.152005]  [<ffffffff811a727f>] ? create_object+0x23f/0x300
[ 6480.152005]  [<ffffffffa02b9958>] btrfs_insert_empty_items+0x78/0xd0 [btrfs]
[ 6480.152005]  [<ffffffffa036041a>] insert_normal_tree_ref.constprop.4+0xa2/0x19a [btrfs]
[ 6480.152005]  [<ffffffffa03605c3>] test_no_shared_qgroup+0xb1/0x1ca [btrfs]
[ 6480.152005]  [<ffffffff8108cad6>] ? local_clock+0x16/0x30
[ 6480.152005]  [<ffffffffa035ef8e>] btrfs_test_qgroups+0x1ae/0x1d7 [btrfs]
[ 6480.152005]  [<ffffffffa03a69d2>] ? ftrace_define_fields_btrfs_space_reservation+0xfd/0xfd [btrfs]
[ 6480.152005]  [<ffffffffa03a6a86>] init_btrfs_fs+0xb4/0x153 [btrfs]
[ 6480.152005]  [<ffffffff81000352>] do_one_initcall+0x102/0x150
[ 6480.152005]  [<ffffffff8103d223>] ? set_memory_nx+0x43/0x50
[ 6480.152005]  [<ffffffff81682668>] ? set_section_ro_nx+0x6d/0x74
[ 6480.152005]  [<ffffffff810d91cc>] load_module+0x1cdc/0x2630
(...)

Therefore initialize the extent buffer as an empty leaf (level 0).

Issue easy to reproduce when btrfs is built as a module via:

    $ for ((i = 1; i <= 1000000; i++)); do rmmod btrfs; modprobe btrfs; done

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-13 09:52:24 -07:00
..
tests Btrfs: fix qgroups sanity test crash or hang 2014-06-13 09:52:24 -07:00
acl.c btrfs: remove useless ACL check 2014-06-09 17:20:42 -07:00
async-thread.c btrfs: fix crash in remount(thread_pool=) case 2014-04-07 10:41:52 -07:00
async-thread.h btrfs: Add trace for btrfs_workqueue alloc/destroy 2014-03-20 17:15:28 -07:00
backref.c Btrfs: fix scrub_print_warning to handle skinny metadata extents 2014-06-09 17:21:17 -07:00
backref.h Btrfs: fix scrub_print_warning to handle skinny metadata extents 2014-06-09 17:21:17 -07:00
btrfs_inode.h btrfs: Drop EXTENT_UPTODATE check in hole punching and direct locking 2014-06-09 17:20:57 -07:00
check-integrity.c btrfs: check_int: propagate out-of-memory error upwards 2014-06-09 17:20:21 -07:00
check-integrity.h block: submit_bio_wait() conversions 2013-11-24 16:33:41 -07:00
compression.c btrfs: return ptr error from compression workspace 2014-06-09 17:20:22 -07:00
compression.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
ctree.c Btrfs: fix leaf corruption after __btrfs_drop_extents 2014-06-09 17:21:10 -07:00
ctree.h Btrfs: make fsync work after cloning into a file 2014-06-09 17:21:16 -07:00
delayed-inode.c btrfs: free delayed node outside of root->inode_lock 2014-06-09 17:21:08 -07:00
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: rework qgroup accounting 2014-06-09 17:20:48 -07:00
delayed-ref.h Btrfs: rework qgroup accounting 2014-06-09 17:20:48 -07:00
dev-replace.c btrfs: replace EINVAL with EOPNOTSUPP for dev_replace raid56 2014-06-09 17:21:12 -07:00
dev-replace.h
dir-item.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
disk-io.c Btrfs: async delayed refs 2014-06-09 17:20:58 -07:00
disk-io.h Btrfs: add sanity tests for new qgroup accounting code 2014-06-09 17:20:49 -07:00
export.c btrfs: remove fs/btrfs/compat.h 2013-11-11 22:03:19 -05:00
export.h
extent_io.c btrfs: new function read_extent_buffer_to_user 2014-06-12 18:21:56 -07:00
extent_io.h btrfs: new function read_extent_buffer_to_user 2014-06-12 18:21:56 -07:00
extent_map.c Btrfs: more efficient btrfs_drop_extent_cache 2014-03-10 15:16:57 -04:00
extent_map.h Btrfs: more efficient btrfs_drop_extent_cache 2014-03-10 15:16:57 -04:00
extent-tree.c btrfs: allocate raid type kobjects dynamically 2014-06-09 17:21:01 -07:00
file-item.c Btrfs: make fsync work after cloning into a file 2014-06-09 17:21:16 -07:00
file.c Btrfs: fix transaction leak during fsync call 2014-06-09 17:21:06 -07:00
free-space-cache.c Btrfs: break up __btrfs_write_out_cache to cut down stack usage 2014-06-09 17:20:55 -07:00
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: remove newline from inode cache kthread name 2014-06-09 17:20:53 -07:00
inode-map.h
inode.c Btrfs: make fsync work after cloning into a file 2014-06-09 17:21:16 -07:00
ioctl.c btrfs: new ioctl TREE_SEARCH_V2 2014-06-13 09:52:19 -07:00
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: return errno instead of -1 from compression 2014-06-09 17:20:21 -07:00
Makefile Btrfs: add sanity tests for new qgroup accounting code 2014-06-09 17:20:49 -07:00
math.h
ordered-data.c btrfs: remove stale newlines from log messages 2014-06-09 17:20:53 -07:00
ordered-data.h btrfs: Cleanup the "_struct" suffix in btrfs_workequeue 2014-03-10 15:17:16 -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: free tmp ulist for qgroup rescan 2014-06-09 17:20:55 -07:00
qgroup.h Btrfs: rework qgroup accounting 2014-06-09 17:20:48 -07:00
raid56.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-04-04 15:31:36 -07:00
raid56.h Btrfs: RAID5 and RAID6 2013-02-01 14:24:23 -05:00
rcu-string.h
reada.c Btrfs: fix unfinished readahead thread for raid5/6 degraded mounting 2014-06-13 09:52:21 -07:00
relocation.c btrfs: remove stale newlines from log messages 2014-06-09 17:20:53 -07:00
root-tree.c Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root 2014-06-09 17:20:40 -07:00
scrub.c Btrfs: fix scrub_print_warning to handle skinny metadata extents 2014-06-09 17:21:17 -07:00
send.c Btrfs: send, use the right limits for xattr names and values 2014-06-09 17:21:00 -07:00
send.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
struct-funcs.c
super.c btrfs: remove stale newlines from log messages 2014-06-09 17:20:53 -07:00
sysfs.c btrfs: allocate raid type kobjects dynamically 2014-06-09 17:21:01 -07:00
sysfs.h btrfs: add simple debugfs interface 2014-03-10 15:15:51 -04:00
transaction.c Btrfs: convert smp_mb__{before,after}_clear_bit 2014-06-10 13:10:47 -07:00
transaction.h Btrfs: add sanity tests for new qgroup accounting code 2014-06-09 17:20:49 -07:00
tree-defrag.c Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root 2014-06-09 17:20:40 -07:00
tree-log.c Btrfs: use helpers for last_trans_log_full_commit instead of opencode 2014-06-09 17:20:45 -07:00
tree-log.h Btrfs: use helpers for last_trans_log_full_commit instead of opencode 2014-06-09 17:20:45 -07:00
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 fs: btrfs: volumes.c: Fix for possible null pointer dereference 2014-06-09 17:21:01 -07:00
volumes.h btrfs: balance filter: add limit of processed chunks 2014-06-09 17:20:26 -07:00
xattr.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-01-30 20:08:20 -08:00
xattr.h btrfs: use generic posix ACL infrastructure 2014-01-25 23:58:18 -05:00
zlib.c btrfs: return errno instead of -1 from compression 2014-06-09 17:20:21 -07:00