INFO: task kworker/u8:16:3684 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:16 state:D stack:21144 pid:3684 tgid:3684 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:4)
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]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
f2fs_down_write fs/f2fs/f2fs.h:2313 [inline]
f2fs_issue_checkpoint+0x38a/0x5b0 fs/f2fs/checkpoint.c:1893
f2fs_balance_fs_bg+0x54a/0x9b0 fs/f2fs/segment.c:544
f2fs_write_node_pages+0x146/0x6e0 fs/f2fs/node.c:2218
do_writepages+0x32e/0x550 mm/page-writeback.c:2598
__writeback_single_inode+0x133/0x1240 fs/fs-writeback.c:1737
writeback_sb_inodes+0x8c8/0x1840 fs/fs-writeback.c:2030
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2107
wb_writeback+0x43f/0xaa0 fs/fs-writeback.c:2218
wb_check_old_data_flush fs/fs-writeback.c:2322 [inline]
wb_do_writeback fs/fs-writeback.c:2375 [inline]
wb_workfn+0xad7/0xee0 fs/fs-writeback.c:2403
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
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
Showing all locks held in the system:
6 locks held by kworker/u8:1/13:
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc90000127bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90000127bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e8987a0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7b0 net/core/net_namespace.c:670
#3: ffff8880370490d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#3: ffff8880370490d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
#3: ffff8880370490d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506
#4: ffff888032060300 (&devlink->lock_key#17){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
#4: ffff888032060300 (&devlink->lock_key#17){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
#4: ffff888032060300 (&devlink->lock_key#17){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506
#5: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#5: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2143
1 lock held by khungtaskd/39:
#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/u8:16/3684:
#0: ffff88801d2dc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88801d2dc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000da3fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000da3fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffff88804a4860d0 (&type->s_umount_key#64){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff88804d521a80 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2313 [inline]
#3: ffff88804d521a80 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_issue_checkpoint+0x38a/0x5b0 fs/f2fs/checkpoint.c:1893
2 locks held by dhcpcd/5462:
#0: ffffffff8e90dde0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: nl80211_pre_doit+0x5f/0x930 net/wireless/nl80211.c:17932
2 locks held by getty/5559:
#0: ffff88814dd890a0 (&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+0x44f/0x1460 drivers/tty/n_tty.c:2211
3 locks held by kworker/0:3/5805:
3 locks held by kworker/u8:20/7430:
#0: ffff88802f8bf138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88802f8bf138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000cf2fbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000cf2fbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194
5 locks held by syz.4.230/7490:
3 locks held by syz-executor/8387:
#0: ffffffff8e90dde0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e90dbd8 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff8e90dbd8 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff8e90dbd8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209
#2: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: wg_set_device_doit+0x15b/0x1f70 drivers/net/wireguard/netlink.c:484
10 locks held by syz-executor/8413:
2 locks held by syz-executor/8430:
#0: ffffffff8e021cc8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e021cc8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e021cc8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
2 locks held by syz-executor/8433:
#0: ffffffff8edb4e40 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8edb4e40 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8edb4e40 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
1 lock held by syz-executor/8438:
#0: ffffffff8e8a58b8 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x37d/0x1df0 drivers/net/tun.c:3078
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8413 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__bfs kernel/locking/lockdep.c:1815 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x1979/0x2cf0 kernel/locking/lockdep.c:5237
Code: 7d 1d 1f 13 25 ff 0f 00 00 39 05 3e 1d 1e 11 73 06 89 05 36 1d 1e 11 48 8b 02 48 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 <48> 8b 00 4c 39 e8 75 f4 48 89 df e9 18 fe ff ff 48 89 fb 48 c7 c7
RSP: 0018:ffffc90004166fd8 EFLAGS: 00000002
RAX: ffffffff95671c88 RBX: 0000000000000101 RCX: 0000000000000002
RDX: ffffffff953e6748 RSI: ffff88802e7ec9c8 RDI: 0000000000000101
RBP: c4803ea906eea61a R08: ffffc90004166fa0 R09: 0000000000000020
R10: ffff888027848090 R11: ffffffff819cebf0 R12: ffffc90004167068
R13: ffffffff925c0820 R14: ffff88802e7ebc80 R15: 0000000000000001
FS: 0000555586558500(0000) GS:ffff888126def000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f08b7e81d68 CR3: 0000000040fea000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline]
do_write_seqcount_begin include/linux/seqlock.h:503 [inline]
psi_write_begin+0xab/0x160 kernel/sched/psi.c:183
psi_task_change+0xd9/0x340 kernel/sched/psi.c:919
psi_enqueue kernel/sched/stats.h:166 [inline]
enqueue_task+0x3e5/0x4c0 kernel/sched/core.c:2096
activate_task kernel/sched/core.c:2135 [inline]
ttwu_do_activate+0x1dc/0x860 kernel/sched/core.c:3631
ttwu_queue kernel/sched/core.c:3894 [inline]
try_to_wake_up+0x721/0x12b0 kernel/sched/core.c:4218
kick_pool+0x47d/0x640 kernel/workqueue.c:1279
__queue_work+0xd0b/0xff0 kernel/workqueue.c:2336
queue_work_on+0x106/0x1c0 kernel/workqueue.c:2386
queue_work include/linux/workqueue.h:669 [inline]
netdevice_queue_work drivers/infiniband/core/roce_gid_mgmt.c:680 [inline]
netdevice_event+0x770/0x8a0 drivers/infiniband/core/roce_gid_mgmt.c:823
notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2268 [inline]
call_netdevice_notifiers net/core/dev.c:2282 [inline]
unregister_netdevice_many_notify+0x1867/0x2330 net/core/dev.c:12383
unregister_netdevice_many net/core/dev.c:12446 [inline]
unregister_netdevice_queue+0x317/0x350 net/core/dev.c:12260
unregister_netdevice include/linux/netdevice.h:3405 [inline]
nsim_destroy+0x1e5/0x680 drivers/net/netdevsim/netdev.c:1180
__nsim_dev_port_del+0x14d/0x1b0 drivers/net/netdevsim/dev.c:1528
nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1540 [inline]
nsim_dev_reload_destroy+0x288/0x490 drivers/net/netdevsim/dev.c:1763
nsim_drv_remove+0x58/0x160 drivers/net/netdevsim/dev.c:1778
device_remove drivers/base/dd.c:569 [inline]
__device_release_driver drivers/base/dd.c:1282 [inline]
device_release_driver_internal+0x46f/0x800 drivers/base/dd.c:1305
bus_remove_device+0x355/0x450 drivers/base/bus.c:616
device_del+0x515/0x8e0 drivers/base/core.c:3878
device_unregister+0x21/0x100 drivers/base/core.c:3919
nsim_bus_dev_del drivers/net/netdevsim/bus.c:483 [inline]
del_device_store+0x2aa/0x360 drivers/net/netdevsim/bus.c:244
kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352
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: 0033:0x7fe944c6e1ff
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:00007ffd5b71e880 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fe944c6e1ff
RDX: 0000000000000001 RSI: 00007ffd5b71e8d0 RDI: 0000000000000005
RBP: 00007fe944cf52cb R08: 0000000000000000 R09: 00007ffd5b71e6d7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffd5b71e8d0 R14: 00007fe9459f4620 R15: 0000000000000003