INFO: task syz.9.1406:13834 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.9.1406 state:D stack:28696 pid:13834 tgid:13826 ppid:12295 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5354 [inline] __schedule+0x165c/0x5520 kernel/sched/core.c:6966 __schedule_loop kernel/sched/core.c:7049 [inline] schedule+0x164/0x360 kernel/sched/core.c:7064 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7121 rwsem_down_read_slowpath+0x6d9/0x940 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1570 __super_lock fs/super.c:60 [inline] super_lock+0x2d6/0x3d0 fs/super.c:122 __iterate_supers+0x126/0x250 fs/super.c:926 ksys_sync fs/sync.c:102 [inline] __ia32_sys_sync+0xa0/0x120 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f327a79c819 RSP: 002b:00007f327b6ad028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f327aa16090 RCX: 00007f327a79c819 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f327aa16090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f327aa16128 R14: 00007f327aa16090 R15: 00007ffd44de8bf8 INFO: task syz.9.1406:13842 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.1406 state:D stack:28440 pid:13842 tgid:13826 ppid:12295 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5354 [inline] __schedule+0x165c/0x5520 kernel/sched/core.c:6966 __schedule_loop kernel/sched/core.c:7049 [inline] schedule+0x164/0x360 kernel/sched/core.c:7064 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7121 rwsem_down_read_slowpath+0x6d9/0x940 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1570 __super_lock fs/super.c:60 [inline] super_lock+0x2d6/0x3d0 fs/super.c:122 __iterate_supers+0x126/0x250 fs/super.c:926 ksys_sync fs/sync.c:102 [inline] __ia32_sys_sync+0xa0/0x120 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f327a79c819 RSP: 002b:00007f327b68c028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f327aa16180 RCX: 00007f327a79c819 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f327aa16180 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f327aa16218 R14: 00007f327aa16180 R15: 00007ffd44de8bf8 Showing all locks held in the system: 3 locks held by kworker/u8:1/13: #0: ffff88801ae8c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3253 [inline] #0: ffff88801ae8c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3361 #1: ffffc90000127c40 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3254 [inline] #1: ffffc90000127c40 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3361 #2: ffffffff8e963368 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #2: ffffffff8e963368 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 4 locks held by kworker/1:1/29: #0: ffff888021aad540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3253 [inline] #0: ffff888021aad540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3361 #1: ffffc90000a47c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3254 [inline] #1: ffffc90000a47c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3361 #2: ffff88802a2f51d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #2: ffff88802a2f51d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff88806143f1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #3: ffff88806143f1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1056 1 lock held by khungtaskd/31: #0: ffffffff8e95d060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e95d060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e95d060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:3/48: #0: ffff88801ae8c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3253 [inline] #0: ffff88801ae8c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3361 #1: ffffc90000b87c40 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3254 [inline] #1: ffffc90000b87c40 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3361 #2: ffffffff8e963368 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #2: ffffffff8e963368 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 2 locks held by getty/5592: #0: ffff8880323140a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:5/5914: 2 locks held by syz-executor/10977: 1 lock held by syz-executor/12529: #0: ffff88805c2500d8 (&type->s_umount_key#63){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805c2500d8 (&type->s_umount_key#63){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88805c2500d8 (&type->s_umount_key#63){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 4 locks held by udevd/12705: #0: ffff88804081abd8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:183 #1: ffff888032e29080 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff888062ce8008 (kn->active#32){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff8880486ac1d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1000 [inline] #3: ffff8880486ac1d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 5 locks held by kworker/1:4/12773: 4 locks held by udevd/12890: #0: ffff88804dfce998 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:183 #1: ffff88806a5a4c80 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff888089138968 (kn->active#33){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888089138968 (kn->active#33){.+.+}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff88806143f1d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1000 [inline] #3: ffff88806143f1d8 (&dev->mutex){....}-{4:4}, at: product_show+0x26/0xa0 drivers/usb/core/sysfs.c:141 1 lock held by syz.9.1406/13834: #0: ffff88807fdd20d8 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88807fdd20d8 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.9.1406/13842: #0: ffff88807fdd20d8 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88807fdd20d8 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.6.1687/15394: #0: ffffffff8fdcf9a0 (bpf_dispatcher_xdp.mutex){+.+.}-{4:4}, at: bpf_dispatcher_change_prog+0xc6/0xd70 kernel/bpf/dispatcher.c:146 1 lock held by modprobe/15414: 2 locks held by rm/15415: #0: ffff8880b863ae60 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: ac 78 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 11 1a 00 fb f4 3c f0 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e607dc0 EFLAGS: 00000246 RAX: 00000000018ddd09 RBX: ffffffff819b129a RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8dfc116d RDI: ffffffff8c288ee0 RBP: ffffffff8e607eb0 R08: ffff8880b86339db R09: 1ffff110170c673b R10: dffffc0000000000 R11: ffffed10170c673c R12: 0000000000000000 R13: 1ffffffff1cd25d8 R14: 0000000000000000 R15: 1ffffffff1cd25d8 FS: 0000000000000000(0000) GS:ffff88812525c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feb092e94e8 CR3: 0000000032b24000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:766 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x36a/0x5f0 kernel/sched/idle.c:352 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451 rest_init+0x2de/0x300 init/main.c:761 start_kernel+0x38a/0x3e0 init/main.c:1219 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147