INFO: task kworker/0:6:3087 blocked for more than 143 seconds. Not tainted 5.8.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:6 D24216 3087 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x88a/0x1cb0 kernel/sched/core.c:4178 schedule+0xcd/0x2b0 kernel/sched/core.c:4253 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1873 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x168/0x270 kernel/sched/completion.c:138 flush_workqueue+0x3ff/0x13e0 kernel/workqueue.c:2832 flush_scheduled_work include/linux/workqueue.h:597 [inline] ath6kl_usb_flush_all drivers/net/wireless/ath/ath6kl/usb.c:476 [inline] hif_detach_htc drivers/net/wireless/ath/ath6kl/usb.c:856 [inline] ath6kl_usb_power_off+0xbe/0xf0 drivers/net/wireless/ath/ath6kl/usb.c:1055 ath6kl_hif_power_off drivers/net/wireless/ath/ath6kl/hif-ops.h:143 [inline] ath6kl_core_init drivers/net/wireless/ath/ath6kl/core.c:255 [inline] ath6kl_core_init+0x236/0x10d0 drivers/net/wireless/ath/ath6kl/core.c:66 ath6kl_usb_probe+0xc30/0x11d0 drivers/net/wireless/ath/ath6kl/usb.c:1155 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:374 really_probe+0x291/0xc90 drivers/base/dd.c:525 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:701 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:807 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x28d/0x430 drivers/base/dd.c:873 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xb09/0x1b40 drivers/base/core.c:2680 usb_set_configuration+0xf05/0x18a0 drivers/usb/core/message.c:2032 usb_generic_driver_probe+0xba/0xf2 drivers/usb/core/generic.c:241 usb_probe_device+0xd9/0x250 drivers/usb/core/driver.c:272 really_probe+0x291/0xc90 drivers/base/dd.c:525 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:701 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:807 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x28d/0x430 drivers/base/dd.c:873 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xb09/0x1b40 drivers/base/core.c:2680 usb_new_device.cold+0x71d/0xfd4 drivers/usb/core/hub.c:2554 hub_port_connect drivers/usb/core/hub.c:5208 [inline] hub_port_connect_change drivers/usb/core/hub.c:5348 [inline] port_event drivers/usb/core/hub.c:5494 [inline] hub_event+0x2361/0x4390 drivers/usb/core/hub.c:5576 process_one_work+0x94c/0x15f0 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x392/0x470 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 INFO: task kworker/0:7:3122 blocked for more than 143 seconds. Not tainted 5.8.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:7 D24656 3122 2 0x80004000 Workqueue: events request_firmware_work_func Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x88a/0x1cb0 kernel/sched/core.c:4178 schedule+0xcd/0x2b0 kernel/sched/core.c:4253 schedule_preempt_disabled+0xc/0x20 kernel/sched/core.c:4312 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10a0 kernel/locking/mutex.c:1103 device_lock include/linux/device.h:768 [inline] ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1108 [inline] ath9k_hif_usb_firmware_cb+0x3ac/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1241 request_firmware_work_func+0x126/0x250 drivers/base/firmware_loader/main.c:1001 process_one_work+0x94c/0x15f0 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x392/0x470 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Showing all locks held in the system: 3 locks held by kworker/1:1/21: #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x82b/0x15f0 kernel/workqueue.c:2240 #1: ffff8881da317da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x85f/0x15f0 kernel/workqueue.c:2244 #2: ffff8881d4439218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:768 [inline] #2: ffff8881d4439218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c5/0x4390 drivers/usb/core/hub.c:5522 1 lock held by khungtaskd/23: #0: ffffffff873124a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5779 3 locks held by kworker/1:2/68: #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x82b/0x15f0 kernel/workqueue.c:2240 #1: ffff8881d5b3fda8 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x85f/0x15f0 kernel/workqueue.c:2244 #2: ffff8881d4531218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:768 [inline] #2: ffff8881d4531218 (&dev->mutex){....}-{3:3}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1108 [inline] #2: ffff8881d4531218 (&dev->mutex){....}-{3:3}, at: ath9k_hif_usb_firmware_cb+0x3ac/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1241 1 lock held by in:imklog/244: #0: ffff8881c8675270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by agetty/252: #0: ffff8881cfef0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900009f62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 5 locks held by kworker/0:6/3087: #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x82b/0x15f0 kernel/workqueue.c:2240 #1: ffff8881c6627da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x85f/0x15f0 kernel/workqueue.c:2244 #2: ffff8881d4471218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:768 [inline] #2: ffff8881d4471218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c5/0x4390 drivers/usb/core/hub.c:5522 #3: ffff8881cd548218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:768 [inline] #3: ffff8881cd548218 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x430 drivers/base/dd.c:850 #4: ffff8881d22c31a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:768 [inline] #4: ffff8881d22c31a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x430 drivers/base/dd.c:850 5 locks held by kworker/1:3/3121: #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x82b/0x15f0 kernel/workqueue.c:2240 #1: ffff8881cd83fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x85f/0x15f0 kernel/workqueue.c:2244 #2: ffff8881d44d1218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:768 [inline] #2: ffff8881d44d1218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c5/0x4390 drivers/usb/core/hub.c:5522 #3: ffff8881d44d4588 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3012 [inline] #3: ffff8881d44d4588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5139 [inline] #3: ffff8881d44d4588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5348 [inline] #3: ffff8881d44d4588 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5494 [inline] #3: ffff8881d44d4588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x217c/0x4390 drivers/usb/core/hub.c:5576 #4: ffff8881d4f69b68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_init+0x1b6/0x2e80 drivers/usb/core/hub.c:4563 3 locks held by kworker/0:7/3122: #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8881da028d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x82b/0x15f0 kernel/workqueue.c:2240 #1: ffff8881cd477da8 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x85f/0x15f0 kernel/workqueue.c:2244 #2: ffff8881d4471218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:768 [inline] #2: ffff8881d4471218 (&dev->mutex){....}-{3:3}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1108 [inline] #2: ffff8881d4471218 (&dev->mutex){....}-{3:3}, at: ath9k_hif_usb_firmware_cb+0x3ac/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1241 3 locks held by kworker/0:8/3125: 6 locks held by kworker/1:5/3225: 5 locks held by kworker/1:6/3235: #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8881d88a6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x82b/0x15f0 kernel/workqueue.c:2240 #1: ffff8881c90c7da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x85f/0x15f0 kernel/workqueue.c:2244 #2: ffff8881d4491218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:768 [inline] #2: ffff8881d4491218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c5/0x4390 drivers/usb/core/hub.c:5522 #3: ffff8881d4494588 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3012 [inline] #3: ffff8881d4494588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5139 [inline] #3: ffff8881d4494588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5348 [inline] #3: ffff8881d4494588 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5494 [inline] #3: ffff8881d4494588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x217c/0x4390 drivers/usb/core/hub.c:5576 #4: ffff8881d4f54b68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_init+0x1b6/0x2e80 drivers/usb/core/hub.c:4563 2 locks held by agetty/6439: #0: ffff8881ce39d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000fc9d2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.8.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xf6/0x16e lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x74/0xb6 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1da/0x1f4 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd6a/0xfd0 kernel/hung_task.c:295 kthread+0x392/0x470 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3235 Comm: kworker/1:6 Not tainted 5.8.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event RIP: 0010:io_serial_in+0x60/0x80 drivers/tty/serial/8250/8250_port.c:447 Code: 0f b6 8d f1 00 00 00 48 8d 7d 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 13 03 5d 40 89 da ec <5b> 0f b6 c0 5d c3 e8 c5 6a 42 ff eb c9 e8 ee 6a 42 ff eb e6 66 90 RSP: 0018:ffff8881c90c7418 EFLAGS: 00000002 RAX: dffffc0000000060 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: ffffffff8226e15c RDI: ffffffff8a2a3be0 RBP: ffffffff8a2a3ba0 R08: 0000000000000001 R09: 0000000000000003 R10: 000000000000000a R11: 0000000000000007 R12: 0000000000000020 R13: fffffbfff14547c6 R14: fffffbfff145477e R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7a9b574000 CR3: 00000001c7596000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_in drivers/tty/serial/8250/8250.h:113 [inline] wait_for_xmitr+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:2060 serial8250_console_putchar+0x1b/0x50 drivers/tty/serial/8250/8250_port.c:3197 uart_console_write+0x59/0x100 drivers/tty/serial/serial_core.c:1949 serial8250_console_write+0x8c5/0xa90 drivers/tty/serial/8250/8250_port.c:3269 call_console_drivers kernel/printk/printk.c:1816 [inline] console_unlock+0x87a/0xcd0 kernel/printk/printk.c:2493 vprintk_emit+0x1b2/0x460 kernel/printk/printk.c:2021 dev_vprintk_emit+0x3eb/0x436 drivers/base/core.c:3883 dev_printk_emit+0xba/0xf1 drivers/base/core.c:3894 __dev_printk+0xcf/0xf5 drivers/base/core.c:3906 _dev_info+0xd7/0x109 drivers/base/core.c:3952 hub_port_init.cold+0x264/0x32f drivers/usb/core/hub.c:4628 hub_port_connect drivers/usb/core/hub.c:5140 [inline] hub_port_connect_change drivers/usb/core/hub.c:5348 [inline] port_event drivers/usb/core/hub.c:5494 [inline] hub_event+0x2191/0x4390 drivers/usb/core/hub.c:5576 process_one_work+0x94c/0x15f0 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x392/0x470 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293