INFO: task udevd:7636 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:22888 pid:7636 tgid:7636 ppid:5181 task_flags:0x400140 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline]
mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547
btrfs_control_ioctl+0x114/0x360 fs/btrfs/super.c:2267
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1866cc5378
RSP: 002b:00007ffe9e916b48 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1866cc5378
RDX: 00007ffe9e916b50 RSI: 0000000090009427 RDI: 0000000000000009
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe9e916b50
R13: 000055af413acf30 R14: 0000000000000009 R15: 00007ffe9e917bb0
INFO: task syz.7.299:8441 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.299 state:D stack:25096 pid:8441 tgid:8439 ppid:7405 task_flags:0x400140 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
__rwbase_read_lock+0xbc/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x127/0x1f0 kernel/locking/rwsem.c:1539
inode_lock_shared include/linux/fs.h:994 [inline]
lookup_slow+0x46/0x70 fs/namei.c:1832
walk_component+0x2d2/0x400 fs/namei.c:2151
lookup_last fs/namei.c:2652 [inline]
path_lookupat+0x163/0x430 fs/namei.c:2676
filename_lookup+0x212/0x570 fs/namei.c:2705
kern_path+0x35/0x50 fs/namei.c:2863
lookup_bdev block/bdev.c:1205 [inline]
bdev_file_open_by_path+0xc8/0x4d0 block/bdev.c:1078
btrfs_scan_one_device+0xa6/0x650 fs/btrfs/volumes.c:1472
btrfs_control_ioctl+0x225/0x360 fs/btrfs/super.c:2254
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f292f9deec9
RSP: 002b:00007f292dc25038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f292fc36090 RCX: 00007f292f9deec9
RDX: 00002000000004c0 RSI: 0000000050009404 RDI: 0000000000000005
RBP: 00007f292fa61f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f292fc36128 R14: 00007f292fc36090 R15: 00007ffda2a3e4b8
INFO: task syz.9.304:8471 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.304 state:D stack:25800 pid:8471 tgid:8470 ppid:7359 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline]
mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547
btrfs_get_tree_super fs/btrfs/super.c:1859 [inline]
btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
btrfs_get_tree+0x40d/0x1830 fs/btrfs/super.c:2123
vfs_get_tree+0x92/0x2b0 fs/super.c:1751
fc_mount fs/namespace.c:1208 [inline]
do_new_mount_fc fs/namespace.c:3651 [inline]
do_new_mount+0x302/0xa10 fs/namespace.c:3727
do_mount fs/namespace.c:4050 [inline]
__do_sys_mount fs/namespace.c:4238 [inline]
__se_sys_mount+0x313/0x410 fs/namespace.c:4215
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f043169066a
RSP: 002b:00007f042f8f5e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f042f8f5ef0 RCX: 00007f043169066a
RDX: 0000200000000000 RSI: 0000200000005600 RDI: 00007f042f8f5eb0
RBP: 0000200000000000 R08: 00007f042f8f5ef0 R09: 0000000000010001
R10: 0000000000010001 R11: 0000000000000246 R12: 0000200000005600
R13: 00007f042f8f5eb0 R14: 000000000000559e R15: 0000200000000500
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d3aa400 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d3aa400 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d3aa400 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/58:
4 locks held by kworker/u8:11/4407:
#0: ffff888140462938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff888140462938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000f577bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000f577bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffff8880647640d0 (&type->s_umount_key#65){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562
#3: ffff88805e47b2a8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
2 locks held by getty/5569:
#0: ffff88823bf388a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/7519:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_control_ioctl+0x114/0x360 fs/btrfs/super.c:2267
1 lock held by udevd/7553:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_control_ioctl+0x114/0x360 fs/btrfs/super.c:2267
1 lock held by udevd/7575:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_control_ioctl+0x114/0x360 fs/btrfs/super.c:2267
1 lock held by udevd/7581:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_control_ioctl+0x114/0x360 fs/btrfs/super.c:2267
1 lock held by udevd/7636:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_control_ioctl+0x114/0x360 fs/btrfs/super.c:2267
1 lock held by udevd/7701:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_control_ioctl+0x114/0x360 fs/btrfs/super.c:2267
4 locks held by syz.7.299/8440:
2 locks held by syz.7.299/8441:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_control_ioctl+0x217/0x360 fs/btrfs/super.c:2249
#1: ffff88805e47b678 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:994 [inline]
#1: ffff88805e47b678 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1832
1 lock held by syz.9.304/8471:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1859 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x40d/0x1830 fs/btrfs/super.c:2123
1 lock held by syz.3.305/8729:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1859 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x40d/0x1830 fs/btrfs/super.c:2123
1 lock held by syz.1.318/8876:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1859 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x40d/0x1830 fs/btrfs/super.c:2123
1 lock held by syz.4.328/8957:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1859 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x40d/0x1830 fs/btrfs/super.c:2123
1 lock held by syz.0.333/9031:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1859 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x40d/0x1830 fs/btrfs/super.c:2123
1 lock held by udevd/9067:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_control_ioctl+0x114/0x360 fs/btrfs/super.c:2267
1 lock held by udevd/9572:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_control_ioctl+0x114/0x360 fs/btrfs/super.c:2267
1 lock held by syz.8.356/9661:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1859 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x40d/0x1830 fs/btrfs/super.c:2123
1 lock held by syz.5.365/9719:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1859 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x40d/0x1830 fs/btrfs/super.c:2123
1 lock held by syz.6.377/9806:
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_super fs/btrfs/super.c:1859 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
#0: ffffffff8d958678 (uuid_mutex){+.+.}-{4:4}, at: btrfs_get_tree+0x40d/0x1830 fs/btrfs/super.c:2123
2 locks held by syz.7.385/9861:
3 locks held by syz.9.387/9866:
1 lock held by syz-executor/9870:
6 locks held by sed/9878:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 58 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: bat_events batadv_dat_purge
RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4879 [inline]
RIP: 0010:__lock_acquire+0x50c/0xd20 kernel/locking/lockdep.c:5187
Code: 49 83 c7 28 41 89 c4 48 39 cb 0f 8d d6 00 00 00 48 83 fb 31 0f 83 92 00 00 00 41 8b 07 25 ff 1f 00 00 48 0f a3 05 b4 00 ed 10 <73> 10 48 69 c0 c8 00 00 00 48 8d 88 10 a3 28 92 eb 40 83 3d 5b 90
RSP: 0018:ffffc9000124f7c8 EFLAGS: 00000003
RAX: 0000000000000a89 RBX: 0000000000000000 RCX: 00000000ffffffff
RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff888019bf0000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81834fa1
R10: 0000000000000000 R11: fffffbfff1d6bbc7 R12: ffffffffffffff05
R13: 0000000000000001 R14: ffff888019bf0bb0 R15: ffff888019bf0b80
FS: 0000000000000000(0000) GS:ffff888127120000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560cdfb07950 CR3: 0000000022db8000 CR4: 00000000003526f0
Call Trace:
reacquire_held_locks+0x127/0x1d0 kernel/locking/lockdep.c:5385
__lock_release kernel/locking/lockdep.c:5574 [inline]
lock_release+0x1b4/0x3e0 kernel/locking/lockdep.c:5889
__local_bh_enable_ip+0x115/0x2e0 kernel/softirq.c:268
local_bh_enable include/linux/bottom_half.h:33 [inline]
spin_unlock_bh include/linux/spinlock_rt.h:111 [inline]
__batadv_dat_purge+0x344/0x400 net/batman-adv/distributed-arp-table.c:185
batadv_dat_purge+0x20/0x70 net/batman-adv/distributed-arp-table.c:204
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245