INFO: task kworker/u8:8:1146 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:8 state:D stack:21112 pid:1146 tgid:1146 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:7)
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x147b/0x4f50 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x164/0x360 kernel/sched/core.c:6960
io_schedule+0x80/0xe0 kernel/sched/core.c:7789
TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline]
txBegin+0x27d/0xc00 fs/jfs/jfs_txnmgr.c:375
jfs_commit_inode+0x1b3/0x530 fs/jfs/inode.c:107
jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x7e4/0x1230 fs/fs-writeback.c:1802
writeback_sb_inodes+0x92e/0x1910 fs/fs-writeback.c:2030
wb_writeback+0x445/0xad0 fs/fs-writeback.c:2216
wb_do_writeback fs/fs-writeback.c:2363 [inline]
wb_workfn+0x3fd/0xf00 fs/fs-writeback.c:2403
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340
worker_thread+0x89f/0xd90 kernel/workqueue.c:3421
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
INFO: task syz-executor:7262 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21440 pid:7262 tgid:7262 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x147b/0x4f50 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x164/0x360 kernel/sched/core.c:6960
wb_wait_for_completion+0x372/0x690 fs/fs-writeback.c:226
__writeback_inodes_sb_nr+0x24c/0x2d0 fs/fs-writeback.c:2808
sync_filesystem+0xa2/0x250 fs/sync.c:54
generic_shutdown_super+0x6f/0x2c0 fs/super.c:622
kill_block_super+0x44/0x90 fs/super.c:1722
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1318
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa8db26bf17
RSP: 002b:00007fff4b5bd898 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fa8db2d471f RCX: 00007fa8db26bf17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff4b5bd950
RBP: 00007fff4b5bd950 R08: 00007fff4b5be950 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff4b5be9e0
R13: 00007fa8db2d471f R14: 000000000005ced9 R15: 00007fff4b5bea20
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d9ae9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9ae9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d9ae9c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:8/1146:
#0: ffff888140466938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff888140466938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc90004af7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90004af7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
2 locks held by dhcpcd/5470:
#0: ffff88805bfee928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2404
#1: ffffffff8eca8838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8eca8838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6826
2 locks held by getty/5564:
#0: ffff88814ed890a0 (&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+0x462/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by kworker/1:3/5800:
#0: ffff88813fe55138 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813fe55138 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc90004cb7bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90004cb7bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffff888054244260 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490
1 lock held by syz-executor/7262:
#0: ffff8880399a40d0 (&type->s_umount_key#83){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff8880399a40d0 (&type->s_umount_key#83){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff8880399a40d0 (&type->s_umount_key#83){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
2 locks held by udevd/7521:
#0: ffffffff8d9ae9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9ae9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d9ae9c0 (rcu_read_lock){....}-{1:3}, at: __d_lookup+0x66/0x780 fs/dcache.c:2435
#1: ffff88805c5ebe48 (&lockref->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#1: ffff88805c5ebe48 (&lockref->lock){+.+.}-{3:3}, at: __d_lookup+0x23e/0x780 fs/dcache.c:2442
3 locks held by udevd/7522:
10 locks held by kworker/u8:23/7870:
3 locks held by kworker/u8:28/9451:
#0: ffff88814dcfa138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88814dcfa138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc900044b7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc900044b7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8eca8838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8eca8838 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4194
3 locks held by syz-executor/9499:
#0: ffffffff8ed10ea0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ed10c98 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff8ed10c98 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff8ed10c98 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1209
#2: ffffffff8eca8838 (rtnl_mutex){+.+.}-{4:4}, at: wg_set_device_doit+0x170/0x2070 drivers/net/wireguard/netlink.c:484
1 lock held by syz-executor/9772:
#0: ffffffff8eca8838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8eca8838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8eca8838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
3 locks held by syz.8.446/9873:
3 locks held by syz.6.447/9869:
=============================================
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:161 [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+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 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: 9869 Comm: syz.6.447 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x28/0x80 kernel/kcov.c:217
Code: 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d 08 37 33 10 65 8b 35 29 37 33 10 81 e6 00 00 ff 00 ba 00 01 00 00 23 91 7c 0b 00 00 <89> d7 09 f7 74 11 85 f6 75 39 85 d2 74 35 83 b9 3c 16 00 00 00 74
RSP: 0018:ffffc90005d3fb08 EFLAGS: 00000246
RAX: ffffffff81fd034d RBX: ffff8880336b35b0 RCX: ffff88802bfb5ac0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880336b35b0
RBP: ffffc90005d3fc58 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff9400025e4bf R12: 1ffff92000ba7f74
R13: dffffc0000000000 R14: 0000000000001000 R15: 0000000000874000
FS: 00007f0ef65266c0(0000) GS:ffff8881268d9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffedbadd130 CR3: 000000002d95c000 CR4: 00000000003526f0
Call Trace:
balance_dirty_pages_ratelimited+0xd/0x20 mm/page-writeback.c:2117
generic_perform_write+0x1dc/0x8b0 mm/filemap.c:4307
shmem_file_write_iter+0xfb/0x120 mm/shmem.c:3490
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x629/0xba0 fs/read_write.c:686
ksys_write+0x156/0x270 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0ef828b58e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f0ef6525da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f0ef65266c0 RCX: 00007f0ef828b58e
RDX: 0000000001000000 RSI: 00007f0eee106000 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000007
R13: 00007f0ef6525ee0 R14: 00007f0ef6525ea0 R15: 00007f0eee106000