INFO: task kworker/0:0H:11 blocked in I/O wait for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:0H state:D stack:26152 pid:11 tgid:11 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: gfs2-glock/syz:syz glock_work_func Call Trace: context_switch kernel/sched/core.c:5352 [inline] __schedule+0x1665/0x5590 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7047 [inline] schedule+0x164/0x360 kernel/sched/core.c:7062 io_schedule+0x7f/0xd0 kernel/sched/core.c:7889 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250 __wait_on_bit_lock+0xec/0x4e0 kernel/sched/wait_bit.c:93 out_of_line_wait_on_bit_lock+0x13b/0x190 kernel/sched/wait_bit.c:120 wait_on_bit_lock_io include/linux/wait_bit.h:221 [inline] __lock_buffer fs/buffer.c:72 [inline] lock_buffer include/linux/buffer_head.h:432 [inline] discard_buffer fs/buffer.c:1603 [inline] block_invalidate_folio+0x370/0x730 fs/buffer.c:1660 folio_invalidate mm/truncate.c:140 [inline] truncate_cleanup_folio+0xcb/0x190 mm/truncate.c:160 truncate_inode_pages_range+0x2ce/0xe30 mm/truncate.c:404 inode_go_inval+0x13c/0x360 fs/gfs2/glops.c:366 do_xmote+0x289/0x760 fs/gfs2/glock.c:699 glock_work_func+0x2a8/0x580 fs/gfs2/glock.c:1011 process_one_work+0x9ab/0x1780 kernel/workqueue.c:3289 process_scheduled_works kernel/workqueue.c:3380 [inline] worker_thread+0xb49/0x1140 kernel/workqueue.c:3461 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz-executor:6559 blocked in I/O wait 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:20880 pid:6559 tgid:6559 ppid:1 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5352 [inline] __schedule+0x1665/0x5590 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7047 [inline] schedule+0x164/0x360 kernel/sched/core.c:7062 io_schedule+0x7f/0xd0 kernel/sched/core.c:7889 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250 __wait_on_bit+0xb9/0x310 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:105 [inline] gfs2_evict_inode+0xa04/0x1130 fs/gfs2/super.c:1462 evict+0x61e/0xb10 fs/inode.c:846 free_local_statfs_inodes fs/gfs2/super.c:1501 [inline] gfs2_put_super+0x635/0x860 fs/gfs2/super.c:632 generic_shutdown_super+0x13d/0x2d0 fs/super.c:646 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 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:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8d5439d9d7 RSP: 002b:00007ffeeb1e6d78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f8d54432050 RCX: 00007f8d5439d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffeeb1e6e30 RBP: 00007ffeeb1e6e30 R08: 00007ffeeb1e7e30 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffeeb1e7ec0 R13: 00007f8d54432050 R14: 000000000002d242 R15: 00007ffeeb1e7f00 Showing all locks held in the system: 3 locks held by kworker/0:1/10: #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc900000f7c40 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 #2: ffffffff8e7637b8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 2 locks held by kworker/0:0H/11: #0: ffff888059c6b140 ((wq_completion)gfs2-glock/syz:syz){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc90000107c40 ((work_completion)(&(&gl->gl_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 1 lock held by khungtaskd/31: #0: ffffffff8e75d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e75d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e75d6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:7/1120: #0: ffff888032201940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc9000591fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 #2: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4198 8 locks held by kworker/u8:8/1159: #0: ffff88801c2b6140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc90005affc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 #2: ffffffff8fbc6988 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:675 #3: ffff88807a2880e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline] #3: ffff88807a2880e0 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff88807a2880e0 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x117/0x3f0 net/devlink/core.c:504 #4: ffff88807a28f248 (&devlink->lock_key#11){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:274 [inline] #4: ffff88807a28f248 (&devlink->lock_key#11){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff88807a28f248 (&devlink->lock_key#11){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x3f0 net/devlink/core.c:504 #5: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x10b/0x730 drivers/net/netdevsim/netdev.c:1177 #6: ffff88805c104d50 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2788 [inline] #6: ffff88805c104d50 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] #6: ffff88805c104d50 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x118e/0x2380 net/core/dev.c:12435 #7: ffffffff8e7638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #7: ffffffff8e7638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 2 locks held by dhcpcd/5497: #0: ffffffff8fbb6560 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x641/0x7f0 net/socket.c:1410 #1: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xf0/0x630 net/8021q/vlan.c:579 2 locks held by getty/5589: #0: ffff8880372f20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/6559: #0: ffff8880336480d8 (&type->s_umount_key#74){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880336480d8 (&type->s_umount_key#74){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880336480d8 (&type->s_umount_key#74){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 1 lock held by syz-executor/9051: #0: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/9298: #0: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 2 locks held by syz-executor/9406: #0: ffffffff8f30dac8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8f30dac8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8f30dac8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 2 locks held by syz-executor/9433: #0: ffffffff8f335f08 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8f335f08 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8f335f08 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 1 lock held by syz-executor/9460: #0: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8fbd5980 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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:162 [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:353 [inline] watchdog+0x1002/0x1060 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 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: 1159 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: netns cleanup_net RIP: 0010:__lock_acquire+0x30a/0x2cf0 kernel/locking/lockdep.c:5175 Code: 49 7c 11 31 f6 85 d2 40 0f 95 c6 31 d2 41 83 be 34 0b 00 00 00 0f 95 c2 c1 e2 0d c1 e6 0e 09 d6 8b 54 24 20 c1 e2 0f 0f b7 d2 <09> f2 41 83 e5 03 41 c1 e5 10 41 09 d5 8b 54 24 10 83 e2 01 c1 e2 RSP: 0018:ffffc900000076b8 EFLAGS: 00000046 RAX: 0000000000000028 RBX: 0000000000000000 RCX: 0000000000000007 RDX: 0000000000000000 RSI: 0000000000002000 RDI: 0000000000000000 RBP: 0000000000000008 R08: ffffffff81773bb5 R09: ffffffff8e75d6a0 R10: ffffc90000007998 R11: ffffffff81b1cb00 R12: 0000000000000000 R13: 0000000000000002 R14: ffff88802917db80 R15: ffff88802917e6d0 FS: 0000000000000000(0000) GS:ffff888125436000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005570aebfdee8 CR3: 000000007ed96000 CR4: 00000000003526f0 Call Trace: lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] __rcu_free_sheaf_prepare+0x12d/0x2a0 mm/slub.c:2940 rcu_free_sheaf+0x31/0x200 mm/slub.c:5842 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869 handle_softirqs+0x22a/0x870 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:739 irq_exit_rcu+0x9/0x30 kernel/softirq.c:756 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline] RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478 Code: 0f 84 44 ff ff ff e8 52 28 21 00 fb eb 44 e8 4a 28 21 00 e8 a5 88 0e 0a 4d 85 f6 74 94 e8 3b 28 21 00 fb 48 c7 c7 e0 fa 74 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 3b 17 RSP: 0018:ffffc90005afec60 EFLAGS: 00000293 RAX: ffffffff81a57ac5 RBX: ffffffff81a5793f RCX: ffff88802917db80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e74fae0 RBP: ffffc90005afed10 R08: ffffffff901249f7 R09: 1ffffffff202493e R10: dffffc0000000000 R11: fffffbfff202493f R12: 0000000000000000 R13: 000000000000005b R14: 0000000000000200 R15: 1ffff92000b5fd90 dev_vprintk_emit+0x355/0x420 drivers/base/core.c:4913 dev_printk_emit+0xee/0x140 drivers/base/core.c:4924 __netdev_printk+0x3e1/0x480 net/core/dev.c:12968 netdev_info+0x11e/0x180 net/core/dev.c:13023 nsim_udp_tunnel_unset_port+0x2d0/0x530 drivers/net/netdevsim/udp_tunnels.c:59 udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:-1 [inline] udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:249 [inline] __udp_tunnel_nic_device_sync+0xb9f/0x1580 net/ipv4/udp_tunnel_nic.c:292 udp_tunnel_nic_flush+0x2cc/0x670 net/ipv4/udp_tunnel_nic.c:694 udp_tunnel_nic_unregister net/ipv4/udp_tunnel_nic.c:901 [inline] udp_tunnel_nic_netdevice_event+0xfbf/0x17e0 net/ipv4/udp_tunnel_nic.c:942 notifier_call_chain+0x1be/0x400 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2289 [inline] call_netdevice_notifiers net/core/dev.c:2303 [inline] unregister_netdevice_many_notify+0x186a/0x2380 net/core/dev.c:12448 unregister_netdevice_many net/core/dev.c:12511 [inline] unregister_netdevice_queue+0x31f/0x360 net/core/dev.c:12325 unregister_netdevice include/linux/netdevice.h:3413 [inline] nsim_destroy+0x21f/0x730 drivers/net/netdevsim/netdev.c:1182 __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:1764 nsim_dev_reload_down+0x8a/0xc0 drivers/net/netdevsim/dev.c:1038 devlink_reload+0x1d1/0x8d0 net/devlink/dev.c:461 devlink_pernet_pre_exit+0x1e6/0x3f0 net/devlink/core.c:507 ops_pre_exit_list net/core/net_namespace.c:161 [inline] ops_undo_list+0x187/0x940 net/core/net_namespace.c:234 cleanup_net+0x56b/0x800 net/core/net_namespace.c:704 process_one_work+0x9ab/0x1780 kernel/workqueue.c:3289 process_scheduled_works kernel/workqueue.c:3380 [inline] worker_thread+0xb49/0x1140 kernel/workqueue.c:3461 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: 49 7c 11 rex.WB jl 0x14 3: 31 f6 xor %esi,%esi 5: 85 d2 test %edx,%edx 7: 40 0f 95 c6 setne %sil b: 31 d2 xor %edx,%edx d: 41 83 be 34 0b 00 00 cmpl $0x0,0xb34(%r14) 14: 00 15: 0f 95 c2 setne %dl 18: c1 e2 0d shl $0xd,%edx 1b: c1 e6 0e shl $0xe,%esi 1e: 09 d6 or %edx,%esi 20: 8b 54 24 20 mov 0x20(%rsp),%edx 24: c1 e2 0f shl $0xf,%edx 27: 0f b7 d2 movzwl %dx,%edx * 2a: 09 f2 or %esi,%edx <-- trapping instruction 2c: 41 83 e5 03 and $0x3,%r13d 30: 41 c1 e5 10 shl $0x10,%r13d 34: 41 09 d5 or %edx,%r13d 37: 8b 54 24 10 mov 0x10(%rsp),%edx 3b: 83 e2 01 and $0x1,%edx 3e: c1 .byte 0xc1 3f: e2 .byte 0xe2