INFO: task syz.3.238:7154 blocked for more than 143 seconds. Not tainted 6.16.0-rc5-syzkaller-00266-g3f31a806a62e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.238 state:D stack:27336 pid:7154 tgid:7153 ppid:5842 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6879 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:747 sync_bdevs+0xfd/0x360 block/bdev.c:1288 ksys_sync+0xb2/0x150 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fda8038e929 RSP: 002b:00007fda812bd038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fda805b5fa0 RCX: 00007fda8038e929 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fda805b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fda805b5fa0 R15: 00007ffd3a884488 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c4dc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4dc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4dc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 2 locks held by khugepaged/38: 3 locks held by kworker/1:1/49: 6 locks held by kworker/0:3/1804: #0: ffff8881442dd948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90005787d10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88802a348198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] ffff88802a348198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fa0 drivers/usb/core/hub.c:5894 #3: ffff888078cc9198 ( &dev->mutex ){....}-{4:4} , at: __wake_up_common_lock kernel/sched/wait.c:105 [inline] , at: __wake_up+0x1c/0x60 kernel/sched/wait.c:127 #4: ffff8880b8439e60 ( &pool->lock ){-.-.}-{2:2} , at: __queue_work+0x26b/0x10f0 kernel/workqueue.c:2301 #5: ffff88801e29d2a8 ( &p->pi_lock ){-.-.}-{2:2} , at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline] , at: try_to_wake_up+0xb2/0x1680 kernel/sched/core.c:4227 3 locks held by kworker/u8:6/1818: #0: ffff88814c33b148 ( (wq_completion)ipv6_addrconf ){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90005767d10 ( (work_completion)(&(&net->ipv6.addr_chk_work)->work) ){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff90362ea8 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4733 2 locks held by kworker/u8:8/4584: #0: ffff8881466c1948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000f59fd10 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 4 locks held by udevd/5203: 2 locks held by getty/5590: #0: ffff88803295e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by napi/wg1-0/5898: #0: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] #0: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 2 locks held by kworker/u8:9/6015: #0: ffff8881466c1948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000bec7d10 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 1 lock held by udevd/6548: #0: ffff888142fa3358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945 1 lock held by syz.3.238/7154: #0: ffff888142fa3358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0xfd/0x360 block/bdev.c:1288 1 lock held by syz.1.755/9376: #0: ffff88805c85e068 (&pipe->mutex){+.+.}-{4:4}, at: pipe_lock fs/pipe.c:91 [inline] #0: ffff88805c85e068 (&pipe->mutex){+.+.}-{4:4}, at: pipe_lock+0x64/0x80 fs/pipe.c:88 1 lock held by syz.1.755/9379: #0: ffff88805c85e068 ( &pipe->mutex ){+.+.}-{4:4} , at: pipe_ioctl+0xca/0x2b0 fs/pipe.c:624 3 locks held by syz.7.758/9387: #0: ffffffff90a9cb20 ( &ops->srcu #2 ){.+.+}-{0:0} , at: srcu_lock_acquire include/linux/srcu.h:161 [inline] , at: srcu_read_lock include/linux/srcu.h:253 [inline] , at: rtnl_link_ops_get+0x113/0x2c0 net/core/rtnetlink.c:574 #1: ffffffff90362ea8 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_lock net/core/rtnetlink.c:80 [inline] , at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] , at: rtnl_newlink+0x600/0x2000 net/core/rtnetlink.c:4054 #2: ffffffff8e5d03b8 ( rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:304 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-syzkaller-00266-g3f31a806a62e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:470 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 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: 49 Comm: kworker/1:1 Not tainted 6.16.0-rc5-syzkaller-00266-g3f31a806a62e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events uhid_device_add_worker RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:410 Code: 22 60 fc 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c c3 cc cc cc cc e8 48 fc c6 fc eb a2 e8 d1 fc RSP: 0018:ffffc90000b97008 EFLAGS: 00000002 RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: ffffffff855bcf90 RDI: ffffffff9b0c72a0 RBP: ffffffff9b0c7260 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000020 R14: fffffbfff3618ea6 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888124813000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c36208a CR3: 0000000052e41000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:137 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline] wait_for_lsr+0x137/0x210 drivers/tty/serial/8250/8250_port.c:2094 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3348 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3371 [inline] serial8250_console_write+0xf83/0x1890 drivers/tty/serial/8250/8250_port.c:3456 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x7fe/0xc60 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 dev_vprintk_emit drivers/base/core.c:4917 [inline] dev_printk_emit+0xfa/0x140 drivers/base/core.c:4928 __dev_printk+0xf5/0x270 drivers/base/core.c:4940 _dev_warn+0xe4/0x120 drivers/base/core.c:4984 hid_parser_main+0x7a4/0xd80 drivers/hid/hid-core.c:664 hid_open_report+0x456/0x830 drivers/hid/hid-core.c:1328 hid_parse include/linux/hid.h:1133 [inline] hid_generic_probe+0x4d/0x90 drivers/hid/hid-generic.c:66 __hid_device_probe drivers/hid/hid-core.c:2724 [inline] hid_device_probe+0x360/0x720 drivers/hid/hid-core.c:2761 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x241/0xa90 drivers/base/dd.c:657 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1a70 drivers/base/core.c:3692 hid_add_device+0x373/0xa60 drivers/hid/hid-core.c:2907 uhid_device_add_worker+0x3e/0x110 drivers/hid/uhid.c:73 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245