INFO: task syz.5.1396:21432 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1396 state:D stack:25800 pid:21432 tgid:21431 ppid:19804 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]
schedule+0x165/0x360 kernel/sched/core.c:7026
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
kthread_flush_worker+0x1c6/0x240 kernel/kthread.c:1564
__alloc_workqueue+0x1470/0x1b70 kernel/workqueue.c:5795
alloc_workqueue_noprof+0xd4/0x210 kernel/workqueue.c:5818
btrfs_alloc_workqueue+0x1ec/0x2d0 fs/btrfs/async-thread.c:112
btrfs_init_workqueues+0x3ac/0x6c0 fs/btrfs/disk-io.c:1995
open_ctree+0x141d/0x3d20 fs/btrfs/disk-io.c:3426
btrfs_fill_super fs/btrfs/super.c:987 [inline]
btrfs_get_tree_super fs/btrfs/super.c:1952 [inline]
btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
btrfs_get_tree+0xf5a/0x1830 fs/btrfs/super.c:2123
vfs_get_tree+0x92/0x2b0 fs/super.c:1752
do_new_mount+0x2a2/0xa30 fs/namespace.c:3750
do_mount fs/namespace.c:4078 [inline]
__do_sys_mount fs/namespace.c:4278 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4255
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: 0033:0x7f7fea72066a
RSP: 002b:00007f7fe8985e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f7fe8985ef0 RCX: 00007f7fea72066a
RDX: 0000200000000000 RSI: 00002000000015c0 RDI: 00007f7fe8985eb0
RBP: 0000200000000000 R08: 00007f7fe8985ef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000015c0
R13: 00007f7fe8985eb0 R14: 000000000000559e R15: 0000200000001600
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d3aa300 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d3aa300 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d3aa300 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/0:2/1137:
2 locks held by kworker/u8:8/1407:
#0: ffff88813ff29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88813ff29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc900054afbc0 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc900054afbc0 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
2 locks held by dhcpcd/5473:
#0: ffffffff8e6c58e0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e65f438 (rtnl_mutex){+.+.}-{4:4}, at: nl80211_pre_doit+0x5f/0x930 net/wireless/nl80211.c:17927
2 locks held by getty/5570:
#0: ffff88823bf440a0 (&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
3 locks held by syz-executor/9212:
1 lock held by syz-executor/10085:
1 lock held by syz-executor/10124:
#0: ffffffff8d00c0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:37 [inline]
#0: ffffffff8d00c0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1667
2 locks held by kworker/1:0/10214:
1 lock held by udevd/10273:
2 locks held by kworker/u8:2/10751:
#0: ffff88813ff29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88813ff29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc900062dfbc0 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc900062dfbc0 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
5 locks held by kworker/u8:16/12866:
1 lock held by syz.5.1396/21432:
#0: ffff8880541ca0d0 (&type->s_umount_key#62/1){+.+.}-{4:4}, at: alloc_super+0x204/0x990 fs/super.c:345
9 locks held by syz-executor/23096:
2 locks held by syz.9.1681/23501:
2 locks held by syz.0.1682/23500:
=============================================
NMI backtrace for cpu 1
CPU: 1 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+0x436/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 10273 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:check_preemption_disabled+0x49/0x120 lib/smp_processor_id.c:53
Code: 8b 0d 6b 58 cd 06 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d 4b 58 cd 06 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f <5d> c3 cc cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24
RSP: 0018:ffffc900046676d0 EFLAGS: 00000286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ff124f69bc48a500
RDX: 0000000000000000 RSI: ffffffff8b1d9940 RDI: ffffffff8b1d9900
RBP: ffffffff820bc08e R08: 0000000000000001 R09: 0000000000000000
R10: ffffc90004667ae0 R11: fffff520008ccf61 R12: 0000000000000000
R13: ffff888056ac6298 R14: 0000000000000000 R15: 0000000000000001
FS: 00007faa539d8880(0000) GS:ffff88812703b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faa53081000 CR3: 0000000066a84000 CR4: 00000000003526f0
Call Trace:
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5831
rt_spin_lock+0x88/0x3e0 kernel/locking/spinlock_rt.c:56
spin_lock include/linux/spinlock_rt.h:44 [inline]
__pte_offset_map_lock+0x13e/0x210 mm/pgtable-generic.c:401
pte_offset_map_lock include/linux/mm.h:3128 [inline]
change_pte_range mm/mprotect.c:286 [inline]
change_pmd_range mm/mprotect.c:567 [inline]
change_pud_range mm/mprotect.c:630 [inline]
change_p4d_range mm/mprotect.c:656 [inline]
change_protection_range mm/mprotect.c:684 [inline]
change_protection+0xefc/0x39d0 mm/mprotect.c:718
mprotect_fixup+0x6fe/0x9c0 mm/mprotect.c:834
do_mprotect_pkey+0x8c5/0xcd0 mm/mprotect.c:990
__do_sys_mprotect mm/mprotect.c:1011 [inline]
__se_sys_mprotect mm/mprotect.c:1008 [inline]
__x64_sys_mprotect+0x80/0x90 mm/mprotect.c:1008
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: 0033:0x7faa53b3cfe7
Code: ef e8 3d fa ff ff 84 c0 75 b9 31 db 48 83 c4 08 48 89 d8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 0f 1f 44 00 00 b8 0a 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 2d 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007fffef481198 EFLAGS: 00000246 ORIG_RAX: 000000000000000a
RAX: ffffffffffffffda RBX: 0000000000000200 RCX: 00007faa53b3cfe7
RDX: 0000000000000001 RSI: 0000000000000200 RDI: 00007faa53081000
RBP: 000055679af5b780 R08: 0000000000000000 R09: 0000000000000200
R10: 000055679af5b7e0 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000faba00 R14: 000055679af601f8 R15: 00007faa5421c39c