INFO: task syz.5.2783:15885 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.5.2783 state:D stack:23880 pid:15885 tgid:15884 ppid:14000 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5258 [inline] __schedule+0x150e/0x5070 kernel/sched/core.c:6866 __schedule_loop kernel/sched/core.c:6948 [inline] schedule+0x165/0x360 kernel/sched/core.c:6963 io_schedule+0x80/0xd0 kernel/sched/core.c:7792 folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1159 [inline] migrate_folio_unmap mm/migrate.c:1249 [inline] migrate_pages_batch+0x14cd/0x35e0 mm/migrate.c:1890 migrate_pages_sync mm/migrate.c:2034 [inline] migrate_pages+0x2006/0x28e0 mm/migrate.c:2116 compact_zone+0x25ba/0x4760 mm/compaction.c:2647 compact_node mm/compaction.c:2916 [inline] compact_nodes mm/compaction.c:2938 [inline] sysctl_compaction_handler+0x3a1/0x7b0 mm/compaction.c:2989 proc_sys_call_handler+0x4cb/0x700 fs/proc/proc_sysctl.c:600 iter_file_splice_write+0x972/0x10b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x101/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5a8/0xcc0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1230 do_sendfile+0x4da/0x7e0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1425 [inline] __se_sys_sendfile64+0xd9/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f83c538f749 RSP: 002b:00007f83c61fc038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f83c55e5fa0 RCX: 00007f83c538f749 RDX: 00002000000000c0 RSI: 0000000000000005 RDI: 0000000000000009 RBP: 00007f83c5413f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f83c55e6038 R14: 00007f83c55e5fa0 R15: 00007ffd8d298c78 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e33f8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e33f8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e33f8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by udevd/5199: 2 locks held by getty/5589: #0: ffff8880354b40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:6/5940: #0: ffff8880206cc548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254 #1: ffffc900044bfb80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255 #2: ffff888143beb198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888143beb198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899 1 lock held by udevd/9264: #0: ffff888025af3358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962 3 locks held by kworker/u9:1/14780: #0: ffff888021f9f948 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254 #1: ffffc9000c9dfb80 ((work_completion)(&hdev->error_reset)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255 #2: ffff8880685f0ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_open net/bluetooth/hci_core.c:428 [inline] #2: ffff8880685f0ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_error_reset+0x159/0x4d0 net/bluetooth/hci_core.c:1035 1 lock held by syz.5.2783/15885: #0: ffff88804265a420 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 6 locks held by kworker/0:8/16266: #0: ffff8880206cc548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254 #1: ffffc9000bcf7b80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255 #2: ffff8880292a5198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff8880292a5198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899 #3: ffffffff99d38780 (&tkd->lock){-.-.}-{2:2}, at: call_timer_fn+0xbe/0x590 kernel/time/timer.c:1745 #4: ffff888028c06e68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff888028c06e68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff888028c06e68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff888028c06e68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2182/0x4ef0 drivers/usb/core/hub.c:5953 #5: ffffffff8efe8ed0 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x14e/0x1850 drivers/usb/core/hub.c:3067 ============================================= 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 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 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:363 [inline] watchdog+0xe40/0xe90 kernel/hung_task.c:557 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 16266 Comm: kworker/0:8 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:__lock_release kernel/locking/lockdep.c:5514 [inline] RIP: 0010:lock_release+0xba/0x3b0 kernel/locking/lockdep.c:5889 Code: 02 00 00 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 48 8b 5c 24 20 fa 48 c7 c7 c3 c3 ab 8d e8 ad ce c7 09 65 ff 05 d6 54 25 11 44 24 20 01 00 00 00 83 3d b7 ff 24 0e 00 0f 84 90 01 00 00 41 RSP: 0018:ffffc90000007c38 EFLAGS: 00000002 RAX: 0000000000000000 RBX: 0000000000000083 RCX: 18390e47d82cf500 RDX: 0000000000010000 RSI: ffffffff8dabc3c3 RDI: ffffffff8be243e0 RBP: ffffc90000007d30 R08: ffffffff8fc3b077 R09: 1ffffffff1f8760e R10: dffffc0000000000 R11: fffffbfff1f8760f R12: dffffc0000000000 R13: ffffffff81af5718 R14: ffff8880b8628258 R15: ffff88807f0d0000 FS: 0000000000000000(0000) GS:ffff8881259e1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f182f77cf98 CR3: 00000000783b2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 000000000300002a DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x70/0x110 kernel/locking/spinlock.c:194 __run_hrtimer kernel/time/hrtimer.c:1773 [inline] __hrtimer_run_queues+0x408/0xc30 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2037 [inline] RIP: 0010:vprintk_emit+0x4d0/0x5f0 kernel/printk/printk.c:2425 Code: 0f 84 34 ff ff ff e8 9f 80 20 00 fb eb 44 e8 97 80 20 00 e8 22 09 c5 09 4d 85 f6 74 94 e8 88 80 20 00 fb 48 c7 c7 a0 37 33 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 28 26 RSP: 0018:ffffc9000bcf7260 EFLAGS: 00000246 RAX: ffffffff81a188f8 RBX: ffffffff81a18751 RCX: 0000000000100000 RDX: ffffc90016ffd000 RSI: 00000000000fffff RDI: ffffffff8e3337a0 RBP: ffffc9000bcf7370 R08: ffffffff8fc3b077 R09: 1ffffffff1f8760e R10: dffffc0000000000 R11: fffffbfff1f8760f R12: 0000000000000000 R13: 000000000000003c R14: 0000000000000200 R15: 1ffff9200179ee50 dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4914 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4925 _dev_info+0x10a/0x160 drivers/base/core.c:4983 hub_port_init+0x5e6/0x28e0 drivers/usb/core/hub.c:4996 hub_port_connect drivers/usb/core/hub.c:5496 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x2573/0x4ef0 drivers/usb/core/hub.c:5953 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246