INFO: task syz-executor:10848 blocked for more than 143 s[ 443.189178][ T39] INFO: task syz-executor:10848 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:20600 pid:10848 tgid:10848 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 fuse_chan_wait_aborted+0x15b/0x250 fs/fuse/dev.c:2212 fuse_conn_destroy+0x1e7/0x3e0 fs/fuse/inode.c:1969 fuse_sb_destroy fs/fuse/inode.c:1988 [inline] fuse_kill_sb_anon+0x1ef/0x270 fs/fuse/inode.c:2001 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:328 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fac2394da57 RSP: 002b:00007ffe431b0a98 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fac239e2048 RCX: 00007fac2394da57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe431b0b50 RBP: 00007ffe431b0b50 R08: 00007ffe431b1b50 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe431b1be0 R13: 00007fac239e2048 R14: 0000000000044ece R15: 00007ffe431b1c20 Showing all locks held in the system: 1 lock held by khungtaskd/39: #0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777 5 locks held by kworker/u8:7/169: #0: ffff88801ae84138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284 #1: ffffc90003a07c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285 #2: ffff888034812310 (&devlink->lock_key#10){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xbc0 drivers/net/netdevsim/dev.c:909 #3: ffff88801ffe5920 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #3: ffff88801ffe5920 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: nsim_dev_trap_report drivers/net/netdevsim/dev.c:862 [inline] #3: ffff88801ffe5920 (&nsim_trap_data->trap_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x1ad/0xbc0 drivers/net/netdevsim/dev.c:922 #4: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #4: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #4: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #4: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 2 locks held by getty/5582: #0: ffff8880338b10a0 (&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 5 locks held by kworker/1:3/5867: #0: ffff888020ada938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284 #1: ffffc90005237c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285 #2: ffff88802abb6210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline] #2: ffff88802abb6210 (&dev->mutex){....}-{4:4}, at: hub_event+0x17c/0x4f60 drivers/usb/core/hub.c:5899 #3: ffff888050a4c210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline] #3: ffff888050a4c210 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1076 #4: ffff8880409ce1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline] #4: ffff8880409ce1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1076 3 locks held by kworker/0:5/5896: #0: ffff88813fe47938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284 #1: ffffc90005717c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285 #2: ffff88801df5b260 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490 7 locks held by kworker/1:5/5913: #0: ffff8880328c8138 ((wq_completion)mld){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284 #1: ffffc90005b87c40 ((work_completion)(&(&idev->mc_dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285 #2: ffff88803c47e628 (&idev->mc_lock){+.+.}-{4:4}, at: mld_dad_work+0x3d/0x5b0 net/ipv6/mcast.c:2293 #3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: mld_sendpack+0x213/0xe40 net/ipv6/mcast.c:1827 #4: ffffffff8e25f260 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #5: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #6: ffff8880b873b9a0 (&rq->__lock){-...}-{2:2}, at: finish_lock_switch kernel/sched/core.c:5121 [inline] #6: ffff8880b873b9a0 (&rq->__lock){-...}-{2:2}, at: finish_task_switch+0x15f/0xbe0 kernel/sched/core.c:5242 1 lock held by syz-executor/10848: #0: ffff88805c2ca0d0 (&type->s_umount_key#80){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805c2ca0d0 (&type->s_umount_key#80){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88805c2ca0d0 (&type->s_umount_key#80){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 4 locks held by udevd/14039: #0: ffff88803d3d1090 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb8/0xe20 fs/seq_file.c:183 #1: ffff888058a7e878 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff88803482b698 (kn->active#24){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff88803482b698 (kn->active#24){.+.+}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff888050a4c210 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1045 [inline] #3: ffff888050a4c210 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 2 locks held by kworker/u8:2/15553: #0: ffff88801ae84938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284 #1: ffffc90004187c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285 5 locks held by syz.4.4110/15599: #0: ffff88802c209f40 (&mdev->req_queue_mutex){+.+.}-{4:4}, at: __video_do_ioctl+0x27e/0xca0 drivers/media/v4l2-core/v4l2-ioctl.c:3095 #1: ffff88802c209ae8 (&dev_instance->mutex){+.+.}-{4:4}, at: __video_do_ioctl+0x476/0xca0 drivers/media/v4l2-core/v4l2-ioctl.c:3101 #2: ffff8880b8640858 ((&pcs->lock)){+.+.}-{3:3}, at: alloc_from_pcs mm/slub.c:4743 [inline] #2: ffff8880b8640858 ((&pcs->lock)){+.+.}-{3:3}, at: slab_alloc_node mm/slub.c:4883 [inline] #2: ffff8880b8640858 ((&pcs->lock)){+.+.}-{3:3}, at: __do_kmalloc_node mm/slub.c:5294 [inline] #2: ffff8880b8640858 ((&pcs->lock)){+.+.}-{3:3}, at: __kmalloc_node_noprof+0x41e/0x7f0 mm/slub.c:5301 #3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: __rt_spin_trylock kernel/locking/spinlock_rt.c:110 [inline] #3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rt_spin_trylock+0x10c/0x2b0 kernel/locking/spinlock_rt.c:118 #4: ffff88813fe39b58 (&barn->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #4: ffff88813fe39b58 (&barn->lock){+.+.}-{3:3}, at: barn_get_empty_sheaf mm/slub.c:3082 [inline] #4: ffff88813fe39b58 (&barn->lock){+.+.}-{3:3}, at: __pcs_replace_empty_main+0x1e8/0x720 mm/slub.c:4635 1 lock held by syz.4.4110/15601: #0: ffff88802c209f40 (&mdev->req_queue_mutex){+.+.}-{4:4}, at: __video_do_ioctl+0x27e/0xca0 drivers/media/v4l2-core/v4l2-ioctl.c:3095 1 lock held by syz.4.4110/15606: #0: ffff88802c209ae8 (&dev_instance->mutex){+.+.}-{4:4}, at: __video_do_ioctl+0x476/0xca0 drivers/media/v4l2-core/v4l2-ioctl.c:3101 1 lock held by syz.6.4112/15613: #0: ffff88803a63d1b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:611 [inline] #0: ffff88803a63d1b0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline] #0: ffff88803a63d1b0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501 2 locks held by modprobe/15611: #0: ffffffff8eae6ef8 (tomoyo_ss){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline] #0: ffffffff8eae6ef8 (tomoyo_ss){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline] #0: ffffffff8eae6ef8 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_read_lock security/tomoyo/common.h:1112 [inline] #0: ffffffff8eae6ef8 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_check_open_permission+0x1d3/0x470 security/tomoyo/file.c:772 #1: ffff88813fe39b58 (&barn->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #1: ffff88813fe39b58 (&barn->lock){+.+.}-{3:3}, at: barn_put_full_sheaf mm/slub.c:3120 [inline] #1: ffff88813fe39b58 (&barn->lock){+.+.}-{3:3}, at: __pcs_replace_empty_main+0x43e/0x720 mm/slub.c:4697 1 lock held by dhcpcd-run-hook/15612: #0: ffff88805abc9db0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:536 [inline] #0: ffff88805abc9db0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x2c2/0x9e0 mm/mmap.c:1308 ============================================= 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 03/18/2026 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: 5913 Comm: kworker/1:5 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: mld mld_dad_work RIP: 0010:__bfs kernel/locking/lockdep.c:1817 [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+0x197b/0x2cf0 kernel/locking/lockdep.c:5239 Code: 14 25 ff 0f 00 00 39 05 9f c3 22 12 73 06 89 05 97 c3 22 12 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 10 54 29 RSP: 0000:ffffc90005b871b0 EFLAGS: 00000002 RAX: ffffffff96587748 RBX: 00000000000003cd RCX: 0000000000000540 RDX: ffffffff96552ae8 RSI: ffff888025bd8d10 RDI: 00000000000003cd RBP: 6a9c3414c8b72422 R08: ffffc90005b87178 R09: 0000000000000020 R10: dffffc0000000000 R11: ffffffff81a12540 R12: ffffffff96750f18 R13: ffffffff936a9030 R14: ffff888025bd8000 R15: 000000000000053f FS: 0000000000000000(0000) GS:ffff888125b64000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4b1eed7dac CR3: 000000002bdb4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5870 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 debug_object_assert_init+0x70/0x340 lib/debugobjects.c:1024 debug_hrtimer_assert_init kernel/time/hrtimer.c:495 [inline] hrtimer_start_range_ns+0x3f/0xef0 kernel/time/hrtimer.c:1477 hrtimer_start include/linux/hrtimer.h:220 [inline] hrtick_cond_restart kernel/sched/core.c:924 [inline] hrtick_schedule_exit kernel/sched/core.c:986 [inline] finish_lock_switch kernel/sched/core.c:5123 [inline] finish_task_switch+0x3cd/0xbe0 kernel/sched/core.c:5242 context_switch kernel/sched/core.c:5390 [inline] __schedule+0x16a6/0x54f0 kernel/sched/core.c:7188 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7369 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline] _raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:198 unlock_rt_mutex_safe kernel/locking/rtmutex.c:350 [inline] rt_mutex_slowunlock+0x4a7/0x8b0 kernel/locking/rtmutex.c:1463 spin_unlock_bh include/linux/spinlock_rt.h:115 [inline] rt6_uncached_list_add net/ipv6/route.c:146 [inline] icmp6_dst_alloc+0x3d3/0x480 net/ipv6/route.c:3355 mld_sendpack+0x6ba/0xe40 net/ipv6/mcast.c:1844 mld_dad_work+0x45/0x5b0 net/ipv6/mcast.c:2294 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