INFO: task kworker/u8:10:1987 blocked in I/O wait for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:10 state:D stack:21240 pid:1987 tgid:1987 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:5) Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x169e/0x54f0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0x164/0x360 kernel/sched/core.c:7282 io_schedule+0x7f/0xd0 kernel/sched/core.c:8109 TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline] txBegin+0x27d/0xc00 fs/jfs/jfs_txnmgr.c:376 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:1584 [inline] __writeback_single_inode+0x75d/0x10e0 fs/fs-writeback.c:1827 writeback_sb_inodes+0x97f/0x1980 fs/fs-writeback.c:2056 wb_writeback+0x445/0xb00 fs/fs-writeback.c:2241 wb_do_writeback fs/fs-writeback.c:2388 [inline] wb_workfn+0x3fd/0xf20 fs/fs-writeback.c:2428 process_one_work+0x9a3/0x1710 kernel/workqueue.c:3312 process_scheduled_works kernel/workqueue.c:3403 [inline] worker_thread+0xba8/0x11e0 kernel/workqueue.c:3489 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz-executor:6965 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20568 pid:6965 tgid:6965 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x169e/0x54f0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0x164/0x360 kernel/sched/core.c:7282 wb_wait_for_completion+0x3e8/0x790 fs/fs-writeback.c:227 __writeback_inodes_sb_nr+0x24c/0x2d0 fs/fs-writeback.c:2847 sync_filesystem+0xa2/0x250 fs/sync.c:54 generic_shutdown_super+0x77/0x2d0 fs/super.c:625 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:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa78a5fda57 RSP: 002b:00007ffe6192d1d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fa78a692048 RCX: 00007fa78a5fda57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe6192d290 RBP: 00007ffe6192d290 R08: 00007ffe6192e290 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe6192e320 R13: 00007fa78a692048 R14: 000000000003adef R15: 00007ffe6192e360 Showing all locks held in the system: 4 locks held by kworker/u8:1/13: #0: ffff888033962138 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284 #1: ffffc90000127c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285 #2: ffffffff8de5f340 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #3: ffffffff8dfc81c0 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 1 lock held by khungtaskd/39: #0: ffffffff8dfc81c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc81c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8dfc81c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777 6 locks held by kworker/u8:6/94: #0: ffff88813fe7c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284 #1: ffffc9000153fc40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285 #2: ffff88802be94310 (&devlink->lock_key#10){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xbc0 drivers/net/netdevsim/dev.c:909 #3: ffff888073a0a520 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #3: ffff888073a0a520 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: nsim_dev_trap_report drivers/net/netdevsim/dev.c:862 [inline] #3: ffff888073a0a520 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x1ad/0xbc0 drivers/net/netdevsim/dev.c:922 #4: ffffffff8dfc81c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #4: ffffffff8dfc81c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #4: ffffffff8dfc81c0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #4: ffffffff8dfc81c0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 #5: ffff88813fe0fd58 (&n->list_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #5: ffff88813fe0fd58 (&n->list_lock){+.+.}-{3:3}, at: get_partial_node_bulk mm/slub.c:3736 [inline] #5: ffff88813fe0fd58 (&n->list_lock){+.+.}-{3:3}, at: __refill_objects_node+0x87/0x560 mm/slub.c:7103 2 locks held by kworker/u8:10/1987: #0: ffff88801f6ae138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284 #1: ffffc90007d5fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285 2 locks held by getty/5579: #0: ffff88823be9e8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:5/5894: #0: ffff88813fe3b938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284 #1: ffffc90005337c40 (rx_mode_work){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285 #2: ffffffff8f383cb8 (rtnl_mutex){+.+.}-{4:4}, at: netdev_rx_mode_work+0x1c/0x460 net/core/dev_addr_lists.c:1312 1 lock held by syz-executor/6965: #0: ffff888035ae80d0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888035ae80d0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888035ae80d0 (&type->s_umount_key#62){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 1 lock held by syz.0.1059/9136: #0: ffff888035ae80d0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff888035ae80d0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz-executor/11315: #0: ffffffff8f383cb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f383cb8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x65f/0xe30 net/ipv6/addrconf.c:5039 3 locks held by syz-executor/11439: #0: ffffffff8f383cb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f383cb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f383cb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4108 #1: ffff888050640f90 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2826 [inline] #1: ffff888050640f90 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] #1: ffff888050640f90 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: do_setlink+0x3d2/0x45a0 net/core/rtnetlink.c:3090 #2: ffff88813fe0fd58 (&n->list_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #2: ffff88813fe0fd58 (&n->list_lock){+.+.}-{3:3}, at: get_partial_node_bulk mm/slub.c:3736 [inline] #2: ffff88813fe0fd58 (&n->list_lock){+.+.}-{3:3}, at: __refill_objects_node+0x87/0x560 mm/slub.c:7103 2 locks held by syz-executor/11525: #0: ffffffff8eaac468 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8eaac468 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8eaac468 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f383cb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f383cb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f383cb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4108 3 locks held by dhcpcd-run-hook/11722: #0: ffffffff8e6e8ab8 (tomoyo_ss){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline] #0: ffffffff8e6e8ab8 (tomoyo_ss){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline] #0: ffffffff8e6e8ab8 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_read_lock security/tomoyo/common.h:1112 [inline] #0: ffffffff8e6e8ab8 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_check_open_permission+0x1d3/0x470 security/tomoyo/file.c:772 #1: ffff88813fe0fd58 (&n->list_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #1: ffff88813fe0fd58 (&n->list_lock){+.+.}-{3:3}, at: get_partial_node_bulk mm/slub.c:3736 [inline] #1: ffff88813fe0fd58 (&n->list_lock){+.+.}-{3:3}, at: __refill_objects_node+0x87/0x560 mm/slub.c:7103 #2: ffffffff8dfc81c0 (rcu_read_lock){....}-{1:3}, at: rtlock_slowlock_locked+0x2a8/0x3c80 kernel/locking/rtmutex.c:1866 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 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+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 94 Comm: kworker/u8:6 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:__bfs kernel/locking/lockdep.c:1755 [inline] RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1862 [inline] RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2798 [inline] RIP: 0010:check_prev_add kernel/locking/lockdep.c:3171 [inline] RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3286 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3910 [inline] RIP: 0010:__lock_acquire+0x1821/0x2cf0 kernel/locking/lockdep.c:5239 Code: 00 0f 83 8a 01 00 00 4e 8b 24 fd 00 48 7f 95 ff c0 25 ff 0f 00 00 89 05 2d 39 df 13 4d 85 e4 0f 84 b2 01 00 00 49 8b 44 24 10 <48> 85 c0 0f 84 1c 0d 00 00 8b 0d 18 39 df 13 39 48 5c 0f 84 67 ff RSP: 0018:ffffc9000153f280 EFLAGS: 00000086 RAX: ffffffff9324c9e8 RBX: 00000000000003cd RCX: ffffffff9623ddd8 RDX: ffffffff96309468 RSI: ffff88801e3d4a68 RDI: 00000000000003cd RBP: 2c2660874325d17e R08: ffffc9000153f248 R09: 0000000000000020 R10: 0000000000000100 R11: ffffffff81a0e130 R12: ffffffff9623ddd8 R13: ffff88801e3d4a68 R14: ffff88801e3d3d80 R15: 0000000000000140 FS: 0000000000000000(0000) GS:ffff888125fb0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2d36bd35c0 CR3: 000000005bf28000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5870 seqcount_lockdep_reader_access+0x55/0x100 include/linux/seqlock.h:73 ktime_get+0x45/0x220 kernel/time/timekeeping.c:965 clockevents_program_event+0x290/0x630 kernel/time/clockevents.c:363 hrtimer_rearm kernel/time/hrtimer.c:2039 [inline] __hrtimer_rearm_deferred+0x273/0x460 kernel/time/hrtimer.c:2059 hrtimer_rearm_deferred_tif include/linux/hrtimer_rearm.h:53 [inline] hrtimer_rearm_deferred include/linux/hrtimer_rearm.h:62 [inline] irqentry_exit_to_kernel_mode_after_preempt include/linux/irq-entry-common.h:513 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:550 [inline] irqentry_exit+0x6a0/0x730 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:198 Code: f7 e8 bd e2 65 f6 f7 c3 00 02 00 00 74 05 e8 80 95 91 f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 74 72 58 f6 65 8b 05 bd b2 3b 07 85 c0 74 18 5b 41 5e c3 cc cc RSP: 0018:ffffc9000153f6c8 EFLAGS: 00000206 RAX: 0000000000000006 RBX: 0000000000000246 RCX: 0000000080000002 RDX: 0000000000000006 RSI: ffffffff8d654652 RDI: 0000000000000001 RBP: ffffc9000153f7d0 R08: ffffffff8f8d5ff7 R09: 1ffffffff1f1abfe R10: dffffc0000000000 R11: fffffbfff1f1abff R12: dffffc0000000000 R13: 1ffff920002a7ee4 R14: ffff88813fe0fd00 R15: ffffc9000153f740 rt_mutex_slowunlock+0x5a4/0x8b0 kernel/locking/rtmutex.c:1476 spin_unlock_irqrestore include/linux/spinlock_rt.h:129 [inline] get_partial_node_bulk mm/slub.c:3771 [inline] __refill_objects_node+0x1e7/0x560 mm/slub.c:7103 refill_objects+0x62/0x3d0 mm/slub.c:7238 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __do_kmalloc_node mm/slub.c:5294 [inline] __kmalloc_node_track_caller_noprof+0x60b/0x7e0 mm/slub.c:5403 kmalloc_reserve net/core/skbuff.c:635 [inline] __alloc_skb+0x2c1/0x7d0 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1383 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline] nsim_dev_trap_report_work+0x29f/0xbc0 drivers/net/netdevsim/dev.c:922 process_one_work+0x9a3/0x1710 kernel/workqueue.c:3312 process_scheduled_works kernel/workqueue.c:3403 [inline] worker_thread+0xba8/0x11e0 kernel/workqueue.c:3489 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245