INFO: task syz.0.283:9368 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.283 state:D stack:25624 pid:9368 tgid:9367 ppid:5807 task_flags:0x400140 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x145f/0x5070 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
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+0x10e/0x160 kernel/kthread.c:1559
__alloc_workqueue+0x1485/0x1b80 kernel/workqueue.c:5797
alloc_workqueue_noprof+0xd4/0x210 kernel/workqueue.c:5820
btrfs_init_workqueues+0x215/0x680 fs/btrfs/disk-io.c:1977
open_ctree+0x141d/0x3d20 fs/btrfs/disk-io.c:3410
btrfs_fill_super fs/btrfs/super.c:983 [inline]
btrfs_get_tree_super fs/btrfs/super.c:1946 [inline]
btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
btrfs_get_tree+0x1061/0x1920 fs/btrfs/super.c:2123
vfs_get_tree+0x92/0x2a0 fs/super.c:1751
fc_mount fs/namespace.c:1199 [inline]
do_new_mount_fc fs/namespace.c:3636 [inline]
do_new_mount+0x302/0xa10 fs/namespace.c:3712
do_mount fs/namespace.c:4035 [inline]
__do_sys_mount fs/namespace.c:4224 [inline]
__se_sys_mount+0x313/0x410 fs/namespace.c:4201
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f53e4360eea
RSP: 002b:00007f53e25c5e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f53e25c5ef0 RCX: 00007f53e4360eea
RDX: 00002000000055c0 RSI: 0000200000000000 RDI: 00007f53e25c5eb0
RBP: 00002000000055c0 R08: 00007f53e25c5ef0 R09: 000000000300000a
R10: 000000000300000a R11: 0000000000000246 R12: 0000200000000000
R13: 00007f53e25c5eb0 R14: 00000000000055a3 R15: 0000200000000080
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:6/1097:
3 locks held by kworker/u8:8/1116:
8 locks held by kworker/u8:13/3544:
2 locks held by getty/5558:
#0: ffff8880277b10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5816:
#0: ffff888034d860d0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff888034d860d0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff888034d860d0 (&type->s_umount_key#74){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
2 locks held by kworker/u8:20/6187:
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc900076efbc0 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc900076efbc0 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
1 lock held by syz.0.283/9368:
#0: ffff8881426d00d0 (&type->s_umount_key#57/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:344
2 locks held by udevd/10786:
2 locks held by kworker/u8:27/11160:
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc90006547bc0 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90006547bc0 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
3 locks held by syz.1.443/11407:
3 locks held by syz.1.443/11411:
3 locks held by syz.5.445/11410:
3 locks held by syz.6.442/11413:
3 locks held by syz.2.444/11415:
=============================================
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 10/25/2025
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 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]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 11413 Comm: syz.6.442 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__sanitizer_cov_trace_pc+0x55/0x80 kernel/kcov.c:222
Code: 09 f7 74 11 85 f6 75 39 85 d2 74 35 83 b9 3c 16 00 00 00 74 2c 8b 91 18 16 00 00 83 fa 02 75 21 48 8b 91 20 16 00 00 48 8b 32 <48> 8d 7e 01 8b 89 1c 16 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2
RSP: 0018:ffffc90005817718 EFLAGS: 00000046
RAX: ffffffff81b86591 RBX: 1ffff92000b02ee8 RCX: ffff8880212a5ac0
RDX: ffffc900197df000 RSI: 000000000007ffff RDI: 0000000000000000
RBP: ffffc900058177f8 R08: ffffea0001290707 R09: 1ffffd40002520e0
R10: dffffc0000000000 R11: fffff940002520e1 R12: 0000000000000000
R13: 0000607ed8fad840 R14: dffffc0000000000 R15: ffff88803c909b00
FS: 00007f4661e4e6c0(0000) GS:ffff888126cef000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558a20f9a180 CR3: 000000005c18e000 CR4: 00000000003526f0
Call Trace:
css_rstat_updated+0x81/0x520 kernel/cgroup/rstat.c:71
memcg_rstat_updated+0x2c/0x220 mm/memcontrol.c:575
count_memcg_events+0xc5/0x240 mm/memcontrol.c:847
memcg1_charge_statistics mm/memcontrol-v1.c:515 [inline]
memcg1_commit_charge+0xb3/0x170 mm/memcontrol-v1.c:579
charge_memcg+0x10b/0x180 mm/memcontrol.c:4734
__mem_cgroup_charge+0x25/0x80 mm/memcontrol.c:4745
mem_cgroup_charge include/linux/memcontrol.h:663 [inline]
shmem_alloc_and_add_folio mm/shmem.c:1942 [inline]
shmem_get_folio_gfp+0x74e/0x1a70 mm/shmem.c:2556
shmem_get_folio mm/shmem.c:2662 [inline]
shmem_write_begin+0x166/0x320 mm/shmem.c:3315
generic_perform_write+0x29d/0x8c0 mm/filemap.c:4314
shmem_file_write_iter+0xfb/0x120 mm/shmem.c:3490
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x5d5/0xb40 fs/read_write.c:686
ksys_write+0x14b/0x260 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4663bee1ff
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007f4661e4ddf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f4663bee1ff
RDX: 0000000001000000 RSI: 00007f4659a2e000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000559d
R10: 000020000000e0c2 R11: 0000000000000293 R12: 0000000000000003
R13: 00007f4661e4def0 R14: 00007f4661e4deb0 R15: 00007f4659a2e000