====================================================== WARNING: possible circular locking dependency detected 5.4.0-rc6+ #0 Not tainted ------------------------------------------------------ syz-executor532/1718 is trying to acquire lock: ffffffff873ebfa0 (driver_lock#2){+.+.}, at: display_open+0x1f/0x1d0 drivers/media/rc/imon.c:475 but task is already holding lock: ffffffff871ede88 (minor_rwsem){++++}, at: usb_open+0x23/0x270 drivers/usb/core/file.c:39 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (minor_rwsem){++++}: down_write+0x92/0x150 kernel/locking/rwsem.c:1534 usb_register_dev drivers/usb/core/file.c:187 [inline] usb_register_dev+0x131/0x670 drivers/usb/core/file.c:156 imon_init_display drivers/media/rc/imon.c:2348 [inline] imon_probe+0x244d/0x2aed drivers/media/rc/imon.c:2431 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361 really_probe+0x281/0x6d0 drivers/base/dd.c:548 driver_probe_device+0x104/0x210 drivers/base/dd.c:721 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430 __device_attach+0x217/0x360 drivers/base/dd.c:894 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490 device_add+0xae6/0x16f0 drivers/base/core.c:2202 usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210 usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266 really_probe+0x281/0x6d0 drivers/base/dd.c:548 driver_probe_device+0x104/0x210 drivers/base/dd.c:721 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430 __device_attach+0x217/0x360 drivers/base/dd.c:894 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490 device_add+0xae6/0x16f0 drivers/base/core.c:2202 usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2537 hub_port_connect drivers/usb/core/hub.c:5184 [inline] hub_port_connect_change drivers/usb/core/hub.c:5324 [inline] port_event drivers/usb/core/hub.c:5470 [inline] hub_event+0x1df8/0x3800 drivers/usb/core/hub.c:5552 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269 worker_thread+0x96/0xe20 kernel/workqueue.c:2415 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 -> #1 (&ictx->lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x158/0x1360 kernel/locking/mutex.c:1103 imon_init_intf0 drivers/media/rc/imon.c:2193 [inline] imon_probe+0xf0c/0x2aed drivers/media/rc/imon.c:2392 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361 really_probe+0x281/0x6d0 drivers/base/dd.c:548 driver_probe_device+0x104/0x210 drivers/base/dd.c:721 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430 __device_attach+0x217/0x360 drivers/base/dd.c:894 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490 device_add+0xae6/0x16f0 drivers/base/core.c:2202 usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210 usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266 really_probe+0x281/0x6d0 drivers/base/dd.c:548 driver_probe_device+0x104/0x210 drivers/base/dd.c:721 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430 __device_attach+0x217/0x360 drivers/base/dd.c:894 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490 device_add+0xae6/0x16f0 drivers/base/core.c:2202 usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2537 hub_port_connect drivers/usb/core/hub.c:5184 [inline] hub_port_connect_change drivers/usb/core/hub.c:5324 [inline] port_event drivers/usb/core/hub.c:5470 [inline] hub_event+0x1df8/0x3800 drivers/usb/core/hub.c:5552 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269 worker_thread+0x96/0xe20 kernel/workqueue.c:2415 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 -> #0 (driver_lock#2){+.+.}: check_prev_add kernel/locking/lockdep.c:2476 [inline] check_prevs_add kernel/locking/lockdep.c:2581 [inline] validate_chain kernel/locking/lockdep.c:2971 [inline] __lock_acquire+0x1f74/0x3b60 kernel/locking/lockdep.c:3955 lock_acquire+0x127/0x320 kernel/locking/lockdep.c:4487 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x158/0x1360 kernel/locking/mutex.c:1103 display_open+0x1f/0x1d0 drivers/media/rc/imon.c:475 usb_open+0x1df/0x270 drivers/usb/core/file.c:48 chrdev_open+0x219/0x5c0 fs/char_dev.c:414 do_dentry_open+0x494/0x1120 fs/open.c:797 do_last fs/namei.c:3408 [inline] path_openat+0x1430/0x3ff0 fs/namei.c:3525 do_filp_open+0x1a1/0x280 fs/namei.c:3555 do_sys_open+0x3c0/0x580 fs/open.c:1097 do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: driver_lock#2 --> &ictx->lock --> minor_rwsem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(minor_rwsem); lock(&ictx->lock); lock(minor_rwsem); lock(driver_lock#2); *** DEADLOCK *** 1 lock held by syz-executor532/1718: #0: ffffffff871ede88 (minor_rwsem){++++}, at: usb_open+0x23/0x270 drivers/usb/core/file.c:39 stack backtrace: CPU: 0 PID: 1718 Comm: syz-executor532 Not tainted 5.4.0-rc6+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xca/0x13e lib/dump_stack.c:113 check_noncircular+0x32e/0x3e0 kernel/locking/lockdep.c:1809 check_prev_add kernel/locking/lockdep.c:2476 [inline] check_prevs_add kernel/locking/lockdep.c:2581 [inline] validate_chain kernel/locking/lockdep.c:2971 [inline] __lock_acquire+0x1f74/0x3b60 kernel/locking/lockdep.c:3955 lock_acquire+0x127/0x320 kernel/locking/lockdep.c:4487 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x158/0x1360 kernel/locking/mutex.c:1103 display_open+0x1f/0x1d0 drivers/media/rc/imon.c:475 usb_open+0x1df/0x270 drivers/usb/core/file.c:48 chrdev_open+0x219/0x5c0 fs/char_dev.c:414 do_dentry_open+0x494/0x1120 fs/open.c:797 do_last fs/namei.c:3408 [inline] path_openat+0x1430/0x3ff0 fs/namei.c:3525 do_filp_open+0x1a1/0x280 fs/namei.c:3555 do_sys_open+0x3c0/0x580 fs/open.c:1097 do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4016a0 Code: 01 f0 ff ff 0f 83 00 0b 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d 8d 24 2d 00 00 75 14 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 d4 0a 00 00 c3 48 83 ec 08 e8 3a 00 00 00 RSP: 002b:00007ffc4d8d45d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00000000004002c8