INFO: task syz-executor.1:27727 blocked for more than 143 seconds. Not tainted 5.14.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:28352 pid:27727 ppid: 26840 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4681 [inline] __schedule+0x941/0x22b0 kernel/sched/core.c:5938 schedule+0xcf/0x270 kernel/sched/core.c:6017 schedule_preempt_disabled+0xc/0x20 kernel/sched/core.c:6076 __mutex_lock_common kernel/locking/mutex.c:1036 [inline] __mutex_lock+0x786/0x1060 kernel/locking/mutex.c:1104 sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2396 usb_open+0x204/0x2e0 drivers/usb/core/file.c:48 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4c3/0x1110 fs/open.c:826 do_open fs/namei.c:3374 [inline] path_openat+0x1c23/0x27f0 fs/namei.c:3507 do_filp_open+0x1aa/0x400 fs/namei.c:3534 do_sys_openat2+0x16d/0x420 fs/open.c:1204 do_sys_open fs/open.c:1220 [inline] __do_sys_openat fs/open.c:1236 [inline] __se_sys_openat fs/open.c:1231 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1231 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4196d4 RSP: 002b:00007f860545dcc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004196d4 RDX: 0000000000000002 RSI: 00007f860545dd60 RDI: 00000000ffffff9c RBP: 00007f860545dd60 R08: 0000000000000000 R09: 000000000000000f R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 00007fff1b9cb2cf R14: 00007f860545e300 R15: 0000000000022000 Showing all locks held in the system: 6 locks held by kworker/0:1/7: #0: ffff88810a417938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88810a417938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:620 [inline] #0: ffff88810a417938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff88810a417938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:617 [inline] #0: ffff88810a417938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: ffff88810a417938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x871/0x15b0 kernel/workqueue.c:2247 #1: ffffc9000007fdb0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15b0 kernel/workqueue.c:2251 #2: ffff88810f9f3220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:754 [inline] #2: ffff88810f9f3220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662 #3: ffff88810f0cc220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:754 [inline] #3: ffff88810f0cc220 (&dev->mutex){....}-{3:3}, at: usb_disconnect.cold+0x43/0x78e drivers/usb/core/hub.c:2216 #4: ffff8881151321a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:754 [inline] #4: ffff8881151321a8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1028 [inline] #4: ffff8881151321a8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal drivers/base/dd.c:1229 [inline] #4: ffff8881151321a8 (&dev->mutex){....}-{3:3}, at: device_release_driver+0x1c/0x40 drivers/base/dd.c:1255 #5: ffffffff87f7a250 (minor_rwsem){++++}-{3:3}, at: usb_deregister_dev+0xaa/0x320 drivers/usb/core/file.c:239 1 lock held by khungtaskd/1277: #0: ffffffff8767e500 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/4303: #0: ffff8881045a0ff0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 2 locks held by syz-executor.5/27705: #0: ffffffff87f7a250 (minor_rwsem){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39 #1: ffff88813f1090d0 (&(sisusb->lock)){+.+.}-{3:3}, at: sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2396 2 locks held by syz-executor.1/27727: #0: ffffffff87f7a250 (minor_rwsem){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39 #1: ffff88813f1090d0 (&(sisusb->lock)){+.+.}-{3:3}, at: sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2396 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1277 Comm: khungtaskd Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x46/0xe0 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1da/0x200 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xcf4/0xf90 kernel/hung_task.c:295 kthread+0x3c0/0x4a0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 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:109 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x1c6/0x250 drivers/acpi/processor_idle.c:553