INFO: task syz-executor.4:20119 blocked for more than 143 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:28240 pid:20119 ppid: 3574 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x947/0x22b0 kernel/sched/core.c:6287 schedule+0xcf/0x270 kernel/sched/core.c:6366 schedule_preempt_disabled+0xc/0x20 kernel/sched/core.c:6425 __mutex_lock_common kernel/locking/mutex.c:669 [inline] __mutex_lock+0xa08/0x12b0 kernel/locking/mutex.c:729 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:822 do_open fs/namei.c:3428 [inline] path_openat+0x1c9a/0x2740 fs/namei.c:3561 do_filp_open+0x1aa/0x400 fs/namei.c:3588 do_sys_openat2+0x16d/0x4d0 fs/open.c:1200 do_sys_open fs/open.c:1216 [inline] __do_sys_openat fs/open.c:1232 [inline] __se_sys_openat fs/open.c:1227 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1227 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: 0033:0x7f32548ba7f4 RSP: 002b:00007f32525facc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f3254a0c260 RCX: 00007f32548ba7f4 RDX: 0000000000000002 RSI: 00007f32525fad60 RDI: 00000000ffffff9c RBP: 00007f32525fad60 R08: 0000000000000000 R09: 000000000000000f R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 00007ffc4bd68bef R14: 00007f32525fb300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/24: #0: ffffffff87681ee0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/2822: #0: ffff88810c81eff0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 6 locks held by kworker/1:4/5816: #0: ffff888102fc0d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888102fc0d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888102fc0d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888102fc0d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888102fc0d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888102fc0d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x8a3/0x1620 kernel/workqueue.c:2268 #1: ffffc90003137db0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x1620 kernel/workqueue.c:2272 #2: ffff88810ce60220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #2: ffff88810ce60220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662 #3: ffff8881124c7220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #3: ffff8881124c7220 (&dev->mutex){....}-{3:3}, at: usb_disconnect.cold+0x43/0x78e drivers/usb/core/hub.c:2216 #4: ffff88811dc151a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #4: ffff88811dc151a8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1032 [inline] #4: ffff88811dc151a8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal drivers/base/dd.c:1233 [inline] #4: ffff88811dc151a8 (&dev->mutex){....}-{3:3}, at: device_release_driver+0x1c/0x40 drivers/base/dd.c:1259 #5: ffffffff87f7e9b0 (minor_rwsem){++++}-{3:3}, at: usb_deregister_dev+0xaa/0x320 drivers/usb/core/file.c:239 2 locks held by agetty/4904: #0: ffff888111f43098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc9000151b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 2 locks held by syz-executor.4/20113: #0: ffffffff87f7e9b0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39 #1: ffff8881135768d0 (&(sisusb->lock)){+.+.}-{3:3}, at: sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2396 2 locks held by syz-executor.4/20119: #0: ffffffff87f7e9b0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39 #1: ffff8881135768d0 (&(sisusb->lock)){+.+.}-{3:3}, at: sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2396 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 24 Comm: khungtaskd Not tainted 5.15.0-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:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x49/0x148 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1d5/0x1f0 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+0xc0f/0xf20 kernel/hung_task.c:295 kthread+0x3c2/0x4a0 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