====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc3-syzkaller-00062-gc061cf420ded #0 Not tainted ------------------------------------------------------ kworker/0:1/9 is trying to acquire lock: ffff888027b8b6c0 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_unregister_queue+0xbe/0x200 block/blk-sysfs.c:854 but task is already holding lock: ffff888027b8b1c8 (&q->q_usage_counter(queue)#53){++++}-{0:0}, at: sd_remove+0x8d/0x110 drivers/scsi/sd.c:4072 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&q->q_usage_counter(queue)#53){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 blk_queue_enter+0xe1/0x600 block/blk-core.c:328 blk_mq_alloc_request+0x4fa/0xaa0 block/blk-mq.c:652 scsi_alloc_request drivers/scsi/scsi_lib.c:1222 [inline] scsi_execute_cmd+0x177/0x1090 drivers/scsi/scsi_lib.c:304 read_capacity_10+0x256/0x9c0 drivers/scsi/sd.c:2766 sd_read_capacity drivers/scsi/sd.c:2834 [inline] sd_revalidate_disk+0x1066/0xbce0 drivers/scsi/sd.c:3734 sd_probe+0x9fa/0x1100 drivers/scsi/sd.c:4010 really_probe+0x2b8/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:459 __device_attach_async_helper+0x22d/0x300 drivers/base/dd.c:987 async_run_entry_fn+0xa8/0x420 kernel/async.c:129 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #1 (&q->limits_lock){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 queue_limits_start_update include/linux/blkdev.h:947 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5034 [inline] blk_mq_update_nr_hw_queues+0xbac/0x1b20 block/blk-mq.c:5068 nbd_start_device+0x16c/0xaa0 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x5dc/0xf40 drivers/block/nbd.c:1579 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&q->sysfs_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_unregister_queue+0xbe/0x200 block/blk-sysfs.c:854 del_gendisk+0x419/0x920 block/genhd.c:710 sd_remove+0x8d/0x110 drivers/scsi/sd.c:4072 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x503/0x7c0 drivers/base/dd.c:1296 bus_remove_device+0x34f/0x420 drivers/base/bus.c:576 device_del+0x57a/0x9b0 drivers/base/core.c:3854 __scsi_remove_device+0x1ad/0x3c0 drivers/scsi/scsi_sysfs.c:1499 scsi_forget_host+0xcf/0x110 drivers/scsi/scsi_scan.c:2068 scsi_remove_host+0x1dd/0x770 drivers/scsi/hosts.c:181 quiesce_and_remove_host drivers/usb/storage/usb.c:949 [inline] usb_stor_disconnect+0x14e/0x1f0 drivers/usb/storage/usb.c:1178 usb_unbind_interface+0x25b/0x940 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x503/0x7c0 drivers/base/dd.c:1296 bus_remove_device+0x34f/0x420 drivers/base/bus.c:576 device_del+0x57a/0x9b0 drivers/base/core.c:3854 usb_disable_device+0x3bf/0x850 drivers/usb/core/message.c:1418 usb_disconnect+0x340/0x950 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+0x1ebc/0x5150 drivers/usb/core/hub.c:5903 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 other info that might help us debug this: Chain exists of: &q->sysfs_lock --> &q->limits_lock --> &q->q_usage_counter(queue)#53 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->q_usage_counter(queue)#53); lock(&q->limits_lock); lock(&q->q_usage_counter(queue)#53); lock(&q->sysfs_lock); *** DEADLOCK *** 8 locks held by kworker/0:1/9: #0: ffff888144ab9d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff888144ab9d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc900000e7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900000e7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffff888028bae190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff888028bae190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5849 #3: ffff888031196190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff888031196190 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x103/0x950 drivers/usb/core/hub.c:2295 #4: ffff88807af0b160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88807af0b160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88807af0b160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffff8880420140e0 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_remove_host+0x34/0x770 drivers/scsi/hosts.c:169 #6: ffff88802a746378 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #6: ffff88802a746378 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #6: ffff88802a746378 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #7: ffff888027b8b1c8 (&q->q_usage_counter(queue)#53){++++}-{0:0}, at: sd_remove+0x8d/0x110 drivers/scsi/sd.c:4072 stack backtrace: CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.13.0-rc3-syzkaller-00062-gc061cf420ded #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_unregister_queue+0xbe/0x200 block/blk-sysfs.c:854 del_gendisk+0x419/0x920 block/genhd.c:710 sd_remove+0x8d/0x110 drivers/scsi/sd.c:4072 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x503/0x7c0 drivers/base/dd.c:1296 bus_remove_device+0x34f/0x420 drivers/base/bus.c:576 device_del+0x57a/0x9b0 drivers/base/core.c:3854 __scsi_remove_device+0x1ad/0x3c0 drivers/scsi/scsi_sysfs.c:1499 scsi_forget_host+0xcf/0x110 drivers/scsi/scsi_scan.c:2068 scsi_remove_host+0x1dd/0x770 drivers/scsi/hosts.c:181 quiesce_and_remove_host drivers/usb/storage/usb.c:949 [inline] usb_stor_disconnect+0x14e/0x1f0 drivers/usb/storage/usb.c:1178 usb_unbind_interface+0x25b/0x940 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x503/0x7c0 drivers/base/dd.c:1296 bus_remove_device+0x34f/0x420 drivers/base/bus.c:576 device_del+0x57a/0x9b0 drivers/base/core.c:3854 usb_disable_device+0x3bf/0x850 drivers/usb/core/message.c:1418 usb_disconnect+0x340/0x950 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+0x1ebc/0x5150 drivers/usb/core/hub.c:5903 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244