Hello, syzbot found the following issue on: HEAD commit: 97ec4d559d93 Merge tag 'block-6.2-2023-01-13' of git://git.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13c11516480000 kernel config: https://syzkaller.appspot.com/x/.config?x=2b6ecad960fc703e dashboard link: https://syzkaller.appspot.com/bug?extid=a7edecbf389d11a369d4 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/9e9ef163c5e9/disk-97ec4d55.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/3dc9c1e25304/vmlinux-97ec4d55.xz kernel image: https://storage.googleapis.com/syzbot-assets/7d859b6029ba/bzImage-97ec4d55.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a7edecbf389d11a369d4@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task kworker/0:5:17966 blocked for more than 143 seconds. Not tainted 6.2.0-rc3-syzkaller-00349-g97ec4d559d93 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:5 state:D stack:24608 pid:17966 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> context_switch kernel/sched/core.c:5293 [inline] __schedule+0xb8a/0x5450 kernel/sched/core.c:6606 schedule+0xde/0x1b0 kernel/sched/core.c:6682 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6741 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0xa48/0x1360 kernel/locking/mutex.c:747 hub_port_connect drivers/usb/core/hub.c:5302 [inline] hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] port_event drivers/usb/core/hub.c:5709 [inline] hub_event+0x27b1/0x4810 drivers/usb/core/hub.c:5791 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> INFO: task kworker/1:2:12207 blocked for more than 144 seconds. Not tainted 6.2.0-rc3-syzkaller-00349-g97ec4d559d93 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:2 state:D stack:27256 pid:12207 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> context_switch kernel/sched/core.c:5293 [inline] __schedule+0xb8a/0x5450 kernel/sched/core.c:6606 schedule+0xde/0x1b0 kernel/sched/core.c:6682 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6741 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0xa48/0x1360 kernel/locking/mutex.c:747 hub_port_connect drivers/usb/core/hub.c:5302 [inline] hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] port_event drivers/usb/core/hub.c:5709 [inline] hub_event+0x27b1/0x4810 drivers/usb/core/hub.c:5791 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8c790fb0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by rcu_tasks_trace/13: #0: ffffffff8c790cb0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by khungtaskd/28: #0: ffffffff8c791b00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x57/0x264 kernel/locking/lockdep.c:6494 1 lock held by kworker/0:1H/52: #0: ffff8880b983b598 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:545 [inline] #0: ffff8880b983b598 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x90/0x120 kernel/sched/core.c:530 2 locks held by getty/4748: #0: ffff88802bd3b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc900015a02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2177 1 lock held by syz-executor.1/5113: 5 locks held by kworker/0:5/17966: #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc9000210fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff88814725d190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:831 [inline] #2: ffff88814725d190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c0/0x4810 drivers/usb/core/hub.c:5737 #3: ffff8881472a04f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3145 [inline] #3: ffff8881472a04f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5301 [inline] #3: ffff8881472a04f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #3: ffff8881472a04f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #3: ffff8881472a04f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x277c/0x4810 drivers/usb/core/hub.c:5791 #4: ffff88814697d468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5302 [inline] #4: ffff88814697d468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #4: ffff88814697d468 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #4: ffff88814697d468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x27b1/0x4810 drivers/usb/core/hub.c:5791 5 locks held by kworker/0:9/19328: #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc9000471fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff888021fff190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:831 [inline] #2: ffff888021fff190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c0/0x4810 drivers/usb/core/hub.c:5737 #3: ffff8881473b24f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3145 [inline] #3: ffff8881473b24f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5301 [inline] #3: ffff8881473b24f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #3: ffff8881473b24f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #3: ffff8881473b24f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x277c/0x4810 drivers/usb/core/hub.c:5791 #4: ffff88801c847a68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5302 [inline] #4: ffff88801c847a68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #4: ffff88801c847a68 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #4: ffff88801c847a68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x27b1/0x4810 drivers/usb/core/hub.c:5791 5 locks held by kworker/0:0/25428: #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc900047efda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff888147237190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:831 [inline] #2: ffff888147237190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c0/0x4810 drivers/usb/core/hub.c:5737 #3: ffff88814724a4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3145 [inline] #3: ffff88814724a4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5301 [inline] #3: ffff88814724a4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #3: ffff88814724a4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #3: ffff88814724a4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x277c/0x4810 drivers/usb/core/hub.c:5791 #4: ffff888147205368 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5302 [inline] #4: ffff888147205368 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #4: ffff888147205368 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #4: ffff888147205368 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x27b1/0x4810 drivers/usb/core/hub.c:5791 5 locks held by kworker/1:23/26875: #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc9000ba3fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff8881472ab190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:831 [inline] #2: ffff8881472ab190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c0/0x4810 drivers/usb/core/hub.c:5737 #3: ffff8881472ae4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3145 [inline] #3: ffff8881472ae4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5301 [inline] #3: ffff8881472ae4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #3: ffff8881472ae4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #3: ffff8881472ae4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x277c/0x4810 drivers/usb/core/hub.c:5791 #4: ffff88814697d468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5302 [inline] #4: ffff88814697d468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #4: ffff88814697d468 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #4: ffff88814697d468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x27b1/0x4810 drivers/usb/core/hub.c:5791 2 locks held by kworker/u4:1/8522: 5 locks held by kworker/1:2/12207: #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888017ef0938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc9000319fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff888147221190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:831 [inline] #2: ffff888147221190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c0/0x4810 drivers/usb/core/hub.c:5737 #3: ffff8881472244f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3145 [inline] #3: ffff8881472244f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5301 [inline] #3: ffff8881472244f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #3: ffff8881472244f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #3: ffff8881472244f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x277c/0x4810 drivers/usb/core/hub.c:5791 #4: ffff888147205368 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5302 [inline] #4: ffff888147205368 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #4: ffff888147205368 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #4: ffff888147205368 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x27b1/0x4810 drivers/usb/core/hub.c:5791 1 lock held by syz-executor.2/16250: #0: ffff8880b983b598 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:545 [inline] #0: ffff8880b983b598 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x90/0x120 kernel/sched/core.c:530 2 locks held by sed/16260: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.2.0-rc3-syzkaller-00349-g97ec4d559d93 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x24/0x18a lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x333/0x3c0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xc75/0xfc0 kernel/hung_task.c:377 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:112 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x1fd/0x2a0 drivers/acpi/processor_idle.c:570 --- This report is generated by a bot. 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