Hello, syzbot found the following issue on: HEAD commit: 68d4209158f4 sub: cdns3: Use predefined PCI vendor ID cons.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing console output: https://syzkaller.appspot.com/x/log.txt?x=11bcdfc7980000 kernel config: https://syzkaller.appspot.com/x/.config?x=cb61872d4d8c5df9 dashboard link: https://syzkaller.appspot.com/bug?extid=c3664338662d943b2dc1 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/c69290425359/disk-68d42091.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/caf4f26a3e85/vmlinux-68d42091.xz kernel image: https://storage.googleapis.com/syzbot-assets/3acdec4b62e6/bzImage-68d42091.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c3664338662d943b2dc1@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task kworker/1:4:4945 blocked for more than 143 seconds. Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:4 state:D stack:21728 pid:4945 tgid:4945 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 adu_disconnect+0xb2/0x1c0 drivers/usb/misc/adutux.c:770 usb_unbind_interface+0x1e8/0x970 drivers/usb/core/driver.c:461 device_remove drivers/base/dd.c:568 [inline] device_remove+0x122/0x170 drivers/base/dd.c:560 __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1295 bus_remove_device+0x22f/0x420 drivers/base/bus.c:574 device_del+0x396/0x9f0 drivers/base/core.c:3871 usb_disable_device+0x36c/0x7f0 drivers/usb/core/message.c:1418 usb_disconnect+0x2e1/0x920 drivers/usb/core/hub.c:2304 hub_port_connect drivers/usb/core/hub.c:5361 [inline] hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] port_event drivers/usb/core/hub.c:5821 [inline] hub_event+0x1bed/0x4f40 drivers/usb/core/hub.c:5903 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6626 5 locks held by kworker/0:2/803: #0: ffff8881066c7548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc90001a4fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffff888109f54190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #2: ffff888109f54190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88812b04c190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff88812b04c190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1004 #4: ffff888115b42160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff888115b42160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1004 2 locks held by getty/2605: #0: ffff8881092ad0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 4 locks held by udevd/4897: #0: ffff88812b7e2540 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xde/0x12c0 fs/seq_file.c:182 #1: ffff888113ed5088 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888112aa41e8 (kn->active#23){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88812b04c190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:1014 [inline] #3: ffff88812b04c190 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 5 locks held by kworker/0:3/4910: 6 locks held by kworker/1:4/4945: #0: ffff8881066c7548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc9000459fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffff888109b69190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #2: ffff888109b69190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88811be2f190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff88811be2f190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2295 #4: ffff88811bf27160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff88811bf27160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff88811bf27160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1292 #5: ffffffff89ad38c8 (adutux_mutex){+.+.}-{3:3}, at: adu_disconnect+0xb2/0x1c0 drivers/usb/misc/adutux.c:770 1 lock held by syz.2.2288/12545: #0: ffffffff89ad38c8 (adutux_mutex){+.+.}-{3:3}, at: adu_release+0xcf/0x720 drivers/usb/misc/adutux.c:323 2 locks held by syz.2.3518/18964: #0: ffffffff899b0110 (minor_rwsem#2){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 #1: ffffffff89ad38c8 (adutux_mutex){+.+.}-{3:3}, at: adu_open+0x5d/0x820 drivers/usb/misc/adutux.c:236 2 locks held by syz.2.3518/18965: #0: ffffffff899b0110 (minor_rwsem#2){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 #1: ffffffff89ad38c8 (adutux_mutex){+.+.}-{3:3}, at: adu_open+0x5d/0x820 drivers/usb/misc/adutux.c:236 1 lock held by syz.4.3520/18970: #0: ffffffff88ec6df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:328 1 lock held by syz.3.3521/18971: #0: ffffffff88ec6df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:296 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </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:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111 --- This report is generated by a bot. 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