======================================================
WARNING: possible circular locking dependency detected
4.14.307-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.4/9728 is trying to acquire lock:
 ("%s-%s""btrfs", name){+.+.}, at: [<ffffffff8135cb4b>] flush_workqueue+0xcb/0x1310 kernel/workqueue.c:2622

but task is already holding lock:
overlayfs: unrecognized mount option "nfs_export=on" or missing value
 (&fs_info->scrub_lock){+.+.}, at: [<ffffffff82b1bdb6>] btrfs_scrub_dev+0x506/0xcd0 fs/btrfs/scrub.c:4217

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&fs_info->scrub_lock){+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:756 [inline]
       __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893
       btrfs_scrub_dev+0x1f3/0xcd0 fs/btrfs/scrub.c:4150
       btrfs_ioctl_scrub fs/btrfs/ioctl.c:4451 [inline]
       btrfs_ioctl+0xba8/0x5b20 fs/btrfs/ioctl.c:5681
       vfs_ioctl fs/ioctl.c:46 [inline]
       file_ioctl fs/ioctl.c:500 [inline]
       do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
       SYSC_ioctl fs/ioctl.c:701 [inline]
       SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
       do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
       entry_SYSCALL_64_after_hwframe+0x5e/0xd3

-> #2 (&fs_devs->device_list_mutex){+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:756 [inline]
       __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893
       __reada_start_machine fs/btrfs/reada.c:765 [inline]
       reada_start_machine_worker+0x1d2/0xa90 fs/btrfs/reada.c:746
       normal_work_helper+0x304/0x1330 fs/btrfs/async-thread.c:376
       process_one_work+0x793/0x14a0 kernel/workqueue.c:2117
       worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251
       kthread+0x30d/0x420 kernel/kthread.c:232
       ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406

-> #1 ((&work->normal_work)){+.+.}:
       process_one_work+0x736/0x14a0 kernel/workqueue.c:2093
       worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251
       kthread+0x30d/0x420 kernel/kthread.c:232
       ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406

-> #0 ("%s-%s""btrfs", name){+.+.}:
       lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
       flush_workqueue+0xfa/0x1310 kernel/workqueue.c:2625
       drain_workqueue+0x177/0x3e0 kernel/workqueue.c:2790
       destroy_workqueue+0x71/0x710 kernel/workqueue.c:4116
       __btrfs_destroy_workqueue fs/btrfs/async-thread.c:436 [inline]
       btrfs_destroy_workqueue+0xf8/0x630 fs/btrfs/async-thread.c:447
       scrub_workers_put+0x90/0x1a0 fs/btrfs/scrub.c:4075
       btrfs_scrub_dev+0x536/0xcd0 fs/btrfs/scrub.c:4219
       btrfs_ioctl_scrub fs/btrfs/ioctl.c:4451 [inline]
       btrfs_ioctl+0xba8/0x5b20 fs/btrfs/ioctl.c:5681
       vfs_ioctl fs/ioctl.c:46 [inline]
       file_ioctl fs/ioctl.c:500 [inline]
       do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
       SYSC_ioctl fs/ioctl.c:701 [inline]
       SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
       do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
       entry_SYSCALL_64_after_hwframe+0x5e/0xd3

other info that might help us debug this:

Chain exists of:
  "%s-%s""btrfs", name --> &fs_devs->device_list_mutex --> &fs_info->scrub_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&fs_info->scrub_lock);
                               lock(&fs_devs->device_list_mutex);
                               lock(&fs_info->scrub_lock);
  lock("%s-%s""btrfs", name);

 *** DEADLOCK ***

1 lock held by syz-executor.4/9728:
 #0:  (&fs_info->scrub_lock){+.+.}, at: [<ffffffff82b1bdb6>] btrfs_scrub_dev+0x506/0xcd0 fs/btrfs/scrub.c:4217

stack backtrace:
CPU: 0 PID: 9728 Comm: syz-executor.4 Not tainted 4.14.307-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258
 check_prev_add kernel/locking/lockdep.c:1905 [inline]
 check_prevs_add kernel/locking/lockdep.c:2022 [inline]
 validate_chain kernel/locking/lockdep.c:2464 [inline]
 __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 flush_workqueue+0xfa/0x1310 kernel/workqueue.c:2625
 drain_workqueue+0x177/0x3e0 kernel/workqueue.c:2790
 destroy_workqueue+0x71/0x710 kernel/workqueue.c:4116
 __btrfs_destroy_workqueue fs/btrfs/async-thread.c:436 [inline]
 btrfs_destroy_workqueue+0xf8/0x630 fs/btrfs/async-thread.c:447
 scrub_workers_put+0x90/0x1a0 fs/btrfs/scrub.c:4075
 btrfs_scrub_dev+0x536/0xcd0 fs/btrfs/scrub.c:4219
 btrfs_ioctl_scrub fs/btrfs/ioctl.c:4451 [inline]
 btrfs_ioctl+0xba8/0x5b20 fs/btrfs/ioctl.c:5681
L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7f9b706b90f9
RSP: 002b:00007f9b6ec2b168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f9b707d8f80 RCX: 00007f9b706b90f9
RDX: 0000000020000100 RSI: 00000000c400941b RDI: 0000000000000004
RBP: 00007f9b70714ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe91952c8f R14: 00007f9b6ec2b300 R15: 0000000000022000
NILFS (loop0): broken superblock, retrying with spare superblock (blocksize = 1024)
NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds
attempt to access beyond end of device
loop3: rw=1, want=2064, limit=2048
BTRFS info (device loop5): enabling inode map caching
BTRFS info (device loop5): trying to use backup root at mount time
print_req_error: I/O error, dev loop3, sector 0
BTRFS info (device loop5): use zlib compression
BTRFS info (device loop5): enabling ssd optimizations
BTRFS info (device loop5): using spread ssd allocation scheme
BTRFS info (device loop5): using free space tree
BTRFS info (device loop5): has skinny extents
attempt to access beyond end of device
loop3: rw=1, want=2064, limit=2048
overlayfs: unrecognized mount option "nfs_export=on" or missing value
team0: Port device ipvlan1 added
syz-executor.0 (9886) used greatest stack depth: 24464 bytes left
BTRFS info (device loop4): enabling inode map caching
BTRFS info (device loop4): trying to use backup root at mount time
BTRFS info (device loop4): use zlib compression
BTRFS info (device loop4): enabling ssd optimizations
BTRFS info (device loop4): using spread ssd allocation scheme
BTRFS info (device loop4): using free space tree
BTRFS info (device loop4): has skinny extents
BTRFS info (device loop4): enabling inode map caching
BTRFS info (device loop4): trying to use backup root at mount time
BTRFS info (device loop4): use zlib compression
BTRFS info (device loop4): enabling ssd optimizations
BTRFS info (device loop4): using spread ssd allocation scheme
BTRFS info (device loop4): using free space tree
BTRFS info (device loop4): has skinny extents
ntfs: volume version 3.1.
ntfs: volume version 3.1.
UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000)
UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000)
REISERFS (device loop1): found reiserfs format "3.5" with non-standard journal
REISERFS (device loop1): using ordered data mode
reiserfs: using flush barriers
REISERFS (device loop1): journal params: device loop1, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop1): checking transaction log (loop1)
REISERFS (device loop1): Using r5 hash to sort names
reiserfs: enabling write barrier flush mode
REISERFS (device loop1): Created .reiserfs_priv - reserved for xattr storage.
UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000)
XFS (loop2): Mounting V4 Filesystem
XFS (loop2): Ending clean mount
XFS (loop2): Unmounting Filesystem
ntfs: volume version 3.1.
REISERFS (device loop1): found reiserfs format "3.5" with non-standard journal
REISERFS (device loop1): using ordered data mode
reiserfs: using flush barriers
REISERFS (device loop1): journal params: device loop1, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop1): checking transaction log (loop1)
REISERFS (device loop1): Using r5 hash to sort names
reiserfs: enabling write barrier flush mode
REISERFS (device loop1): Created .reiserfs_priv - reserved for xattr storage.
XFS (loop2): Mounting V4 Filesystem
XFS (loop2): Ending clean mount
syz-executor.2 (10165) used greatest stack depth: 23424 bytes left
XFS (loop2): Unmounting Filesystem
REISERFS (device loop1): found reiserfs format "3.5" with non-standard journal
REISERFS (device loop1): using ordered data mode
ntfs: volume version 3.1.
reiserfs: using flush barriers
REISERFS (device loop1): journal params: device loop1, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop1): checking transaction log (loop1)
REISERFS (device loop1): Using r5 hash to sort names
reiserfs: enabling write barrier flush mode
REISERFS (device loop1): Created .reiserfs_priv - reserved for xattr storage.
REISERFS (device loop1): found reiserfs format "3.5" with non-standard journal
XFS (loop4): Mounting V4 Filesystem
REISERFS (device loop1): using ordered data mode
reiserfs: using flush barriers
XFS (loop4): Ending clean mount
REISERFS (device loop1): journal params: device loop1, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop1): checking transaction log (loop1)
REISERFS (device loop1): Using r5 hash to sort names
reiserfs: enabling write barrier flush mode
REISERFS (device loop1): Created .reiserfs_priv - reserved for xattr storage.
XFS (loop2): Mounting V4 Filesystem
XFS (loop4): Unmounting Filesystem
XFS (loop2): Ending clean mount
syz-executor.2 (10246) used greatest stack depth: 23312 bytes left
XFS (loop2): Unmounting Filesystem
XFS (loop5): Mounting V4 Filesystem
XFS (loop5): Ending clean mount
XFS (loop5): Unmounting Filesystem
vivid-000: =================  START STATUS  =================
vivid-000: FM Deviation: 75000
bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
vivid-000: ==================  END STATUS  ==================
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
vivid-000: =================  START STATUS  =================
vivid-000: FM Deviation: 75000
vivid-000: ==================  END STATUS  ==================
vivid-000: =================  START STATUS  =================
vivid-000: FM Deviation: 75000
vivid-000: ==================  END STATUS  ==================
vivid-000: =================  START STATUS  =================
vivid-000: FM Deviation: 75000
vivid-000: ==================  END STATUS  ==================
vivid-006: =================  START STATUS  =================
vivid-006: FM Deviation: 75000
vivid-006: ==================  END STATUS  ==================