====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc3-syzkaller-g6f6ecce59d99 #0 Not tainted ------------------------------------------------------ kworker/0:3/3852 is trying to acquire lock: ff6000001a4ffad0 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_unregister_queue+0xb2/0x276 block/blk-sysfs.c:854 but task is already holding lock: ff6000001a4ff5e0 (&q->q_usage_counter(queue)#22){++++}-{0:0}, at: sd_remove+0x88/0x146 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)#22){++++}-{0:0}: lock_acquire.part.0+0x2c4/0x81a kernel/locking/lockdep.c:5849 lock_acquire+0x74/0x98 kernel/locking/lockdep.c:5822 blk_queue_enter+0x492/0x5a8 block/blk-core.c:328 blk_mq_alloc_request+0x59c/0x83a block/blk-mq.c:652 scsi_alloc_request drivers/scsi/scsi_lib.c:1222 [inline] scsi_execute_cmd+0x206/0xee0 drivers/scsi/scsi_lib.c:304 read_capacity_10+0x170/0x62c drivers/scsi/sd.c:2766 sd_read_capacity+0x548/0xb18 drivers/scsi/sd.c:2834 sd_revalidate_disk.isra.0+0xfdc/0x9c26 drivers/scsi/sd.c:3734 sd_probe+0x820/0xe80 drivers/scsi/sd.c:4010 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x232/0x9be drivers/base/dd.c:658 __driver_probe_device+0x1d4/0x3f2 drivers/base/dd.c:800 driver_probe_device+0x60/0x1ce drivers/base/dd.c:830 __device_attach_driver+0x1e2/0x2fc drivers/base/dd.c:958 bus_for_each_drv+0x142/0x1da drivers/base/bus.c:459 __device_attach_async_helper+0x1c2/0x26c drivers/base/dd.c:987 async_run_entry_fn+0x9a/0x4ac kernel/async.c:129 process_one_work+0x968/0x1f38 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x5be/0xdc6 kernel/workqueue.c:3391 kthread+0x28c/0x3a4 kernel/kthread.c:389 ret_from_fork+0xe/0x18 arch/riscv/kernel/entry.S:327 -> #1 (&q->limits_lock){+.+.}-{4:4}: lock_acquire.part.0+0x2c4/0x81a kernel/locking/lockdep.c:5849 lock_acquire+0x74/0x98 kernel/locking/lockdep.c:5822 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x166/0x1082 kernel/locking/mutex.c:735 mutex_lock_nested+0x14/0x1c kernel/locking/mutex.c:787 queue_limits_start_update include/linux/blkdev.h:947 [inline] __blk_mq_update_nr_hw_queues+0x79e/0x13d4 block/blk-mq.c:5034 blk_mq_update_nr_hw_queues+0x32/0x4a block/blk-mq.c:5068 nbd_start_device+0x140/0xc00 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+0x474/0xd90 drivers/block/nbd.c:1579 blkdev_ioctl+0x23c/0xca0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __riscv_sys_ioctl+0x18e/0x1e2 fs/ioctl.c:892 syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:90 do_trap_ecall_u+0x1aa/0x216 arch/riscv/kernel/traps.c:331 handle_exception+0x146/0x152 arch/riscv/kernel/entry.S:197 -> #0 (&q->sysfs_lock){+.+.}-{4:4}: check_noncircular+0x2ba/0x354 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 kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x2e4e/0x8594 kernel/locking/lockdep.c:5226 lock_acquire.part.0+0x2c4/0x81a kernel/locking/lockdep.c:5849 lock_acquire+0x74/0x98 kernel/locking/lockdep.c:5822 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x166/0x1082 kernel/locking/mutex.c:735 mutex_lock_nested+0x14/0x1c kernel/locking/mutex.c:787 blk_unregister_queue+0xb2/0x276 block/blk-sysfs.c:854 del_gendisk+0x2ac/0x9f4 block/genhd.c:710 sd_remove+0x88/0x146 drivers/scsi/sd.c:4072 device_remove drivers/base/dd.c:569 [inline] device_remove+0x11a/0x15c drivers/base/dd.c:561 __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x3f0/0x572 drivers/base/dd.c:1296 device_release_driver+0x1e/0x28 drivers/base/dd.c:1319 bus_remove_device+0x1f4/0x3d2 drivers/base/bus.c:576 device_del+0x324/0x898 drivers/base/core.c:3854 __scsi_remove_device+0x300/0x3c8 drivers/scsi/scsi_sysfs.c:1499 scsi_forget_host+0x138/0x17e drivers/scsi/scsi_scan.c:2068 scsi_remove_host+0xec/0x2fe drivers/scsi/hosts.c:181 quiesce_and_remove_host drivers/usb/storage/usb.c:949 [inline] usb_stor_disconnect+0xf2/0x222 drivers/usb/storage/usb.c:1178 usb_unbind_interface+0x1b4/0x86c drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] device_remove+0x11a/0x15c drivers/base/dd.c:561 __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x3f0/0x572 drivers/base/dd.c:1296 device_release_driver+0x1e/0x28 drivers/base/dd.c:1319 bus_remove_device+0x1f4/0x3d2 drivers/base/bus.c:576 device_del+0x324/0x898 drivers/base/core.c:3854 usb_disable_device+0x2f8/0x6f6 drivers/usb/core/message.c:1418 usb_disconnect+0x28e/0x8a2 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+0x1976/0x48a4 drivers/usb/core/hub.c:5903 process_one_work+0x968/0x1f38 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x5be/0xdc6 kernel/workqueue.c:3391 kthread+0x28c/0x3a4 kernel/kthread.c:389 ret_from_fork+0xe/0x18 arch/riscv/kernel/entry.S:327 other info that might help us debug this: Chain exists of: &q->sysfs_lock --> &q->limits_lock --> &q->q_usage_counter(queue)#22 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->q_usage_counter(queue)#22); lock(&q->limits_lock); lock(&q->q_usage_counter(queue)#22); lock(&q->sysfs_lock); *** DEADLOCK *** 8 locks held by kworker/0:3/3852: #0: ff600000156cc948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x848/0x1f38 kernel/workqueue.c:3204 #1: ff2000000d787c90 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x870/0x1f38 kernel/workqueue.c:3204 #2: ff6000001c930190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #2: ff6000001c930190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bc/0x48a4 drivers/usb/core/hub.c:5849 #3: ff6000002ff3d190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #3: ff6000002ff3d190 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x108/0x8a2 drivers/usb/core/hub.c:2295 #4: ff6000001d735160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #4: ff6000001d735160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ff6000001d735160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x9c/0x572 drivers/base/dd.c:1293 #5: ff600000309ac0e0 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_remove_host+0x2e/0x2fe drivers/scsi/hosts.c:169 #6: ff6000002fa5e378 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #6: ff6000002fa5e378 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #6: ff6000002fa5e378 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x9c/0x572 drivers/base/dd.c:1293 #7: ff6000001a4ff5e0 (&q->q_usage_counter(queue)#22){++++}-{0:0}, at: sd_remove+0x88/0x146 drivers/scsi/sd.c:4072 stack backtrace: CPU: 0 UID: 0 PID: 3852 Comm: kworker/0:3 Not tainted 6.13.0-rc3-syzkaller-g6f6ecce59d99 #0 Hardware name: riscv-virtio,qemu (DT) Workqueue: usb_hub_wq hub_event Call Trace: [] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:132 [] show_stack+0x30/0x3c arch/riscv/kernel/stacktrace.c:138 [] __dump_stack lib/dump_stack.c:94 [inline] [] dump_stack_lvl+0x12e/0x1a6 lib/dump_stack.c:120 [] dump_stack+0x1c/0x24 lib/dump_stack.c:129 [] print_circular_bug+0x3a2/0x42c kernel/locking/lockdep.c:2074 [] check_noncircular+0x2ba/0x354 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 kernel/locking/lockdep.c:3904 [inline] [] __lock_acquire+0x2e4e/0x8594 kernel/locking/lockdep.c:5226 [] lock_acquire.part.0+0x2c4/0x81a kernel/locking/lockdep.c:5849 [] lock_acquire+0x74/0x98 kernel/locking/lockdep.c:5822 [] __mutex_lock_common kernel/locking/mutex.c:585 [inline] [] __mutex_lock+0x166/0x1082 kernel/locking/mutex.c:735 [] mutex_lock_nested+0x14/0x1c kernel/locking/mutex.c:787 [] blk_unregister_queue+0xb2/0x276 block/blk-sysfs.c:854 [] del_gendisk+0x2ac/0x9f4 block/genhd.c:710 [] sd_remove+0x88/0x146 drivers/scsi/sd.c:4072 [] device_remove drivers/base/dd.c:569 [inline] [] device_remove+0x11a/0x15c drivers/base/dd.c:561 [] __device_release_driver drivers/base/dd.c:1273 [inline] [] device_release_driver_internal+0x3f0/0x572 drivers/base/dd.c:1296 [] device_release_driver+0x1e/0x28 drivers/base/dd.c:1319 [] bus_remove_device+0x1f4/0x3d2 drivers/base/bus.c:576 [] device_del+0x324/0x898 drivers/base/core.c:3854 [] __scsi_remove_device+0x300/0x3c8 drivers/scsi/scsi_sysfs.c:1499 [] scsi_forget_host+0x138/0x17e drivers/scsi/scsi_scan.c:2068 [] scsi_remove_host+0xec/0x2fe drivers/scsi/hosts.c:181 [] quiesce_and_remove_host drivers/usb/storage/usb.c:949 [inline] [] usb_stor_disconnect+0xf2/0x222 drivers/usb/storage/usb.c:1178 [] usb_unbind_interface+0x1b4/0x86c drivers/usb/core/driver.c:458 [] device_remove drivers/base/dd.c:569 [inline] [] device_remove+0x11a/0x15c drivers/base/dd.c:561 [] __device_release_driver drivers/base/dd.c:1273 [inline] [] device_release_driver_internal+0x3f0/0x572 drivers/base/dd.c:1296 [] device_release_driver+0x1e/0x28 drivers/base/dd.c:1319 [] bus_remove_device+0x1f4/0x3d2 drivers/base/bus.c:576 [] device_del+0x324/0x898 drivers/base/core.c:3854 [] usb_disable_device+0x2f8/0x6f6 drivers/usb/core/message.c:1418 [] usb_disconnect+0x28e/0x8a2 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+0x1976/0x48a4 drivers/usb/core/hub.c:5903 [] process_one_work+0x968/0x1f38 kernel/workqueue.c:3229 [] process_scheduled_works kernel/workqueue.c:3310 [inline] [] worker_thread+0x5be/0xdc6 kernel/workqueue.c:3391 [] kthread+0x28c/0x3a4 kernel/kthread.c:389 [] ret_from_fork+0xe/0x18 arch/riscv/kernel/entry.S:327