input: Steam Controller as /devices/platform/dummy_hcd.2/usb3/3-1/3-1:0.0/0003:28DE:1102.0003/input/input8 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.380/6075 is trying to acquire lock: ffffffff8cd3d7a8 (input_mutex){+.+.}-{3:3}, at: input_register_device+0xb66/0x1140 drivers/input/input.c:2422 but task is already holding lock: ffff888059861ee0 (&hdev->ll_open_lock){+.+.}-{3:3}, at: hid_hw_close+0x2c/0xd0 drivers/hid/hid-core.c:2153 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&hdev->ll_open_lock){+.+.}-{3:3}: __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_killable_nested+0x17/0x20 kernel/locking/mutex.c:758 hid_hw_open+0x23/0x160 drivers/hid/hid-core.c:2127 input_open_device+0x16c/0x2e0 drivers/input/input.c:640 mousedev_open_device+0xc3/0x150 drivers/input/mousedev.c:430 mousedev_open+0x2e5/0x4a0 drivers/input/mousedev.c:556 chrdev_open+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3608 [inline] path_openat+0x2682/0x2f30 fs/namei.c:3742 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #1 (&dev->mutex#2){+.+.}-{3:3}: __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_interruptible_nested+0x17/0x20 kernel/locking/mutex.c:765 input_register_handle+0x67/0x3a0 drivers/input/input.c:2588 kbd_connect+0xbf/0x130 drivers/tty/vt/keyboard.c:1577 input_attach_handler drivers/input/input.c:1046 [inline] input_register_device+0xda7/0x1140 drivers/input/input.c:2429 acpi_button_add+0x6ba/0xae0 drivers/acpi/button.c:579 acpi_device_probe+0xa3/0x300 drivers/acpi/bus.c:1013 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __driver_attach+0x46b/0x670 drivers/base/dd.c:1164 bus_for_each_dev+0x175/0x1e0 drivers/base/bus.c:303 bus_add_driver+0x30a/0x5a0 drivers/base/bus.c:620 driver_register+0x32d/0x430 drivers/base/driver.c:240 do_one_initcall+0x1ee/0x680 init/main.c:1302 do_initcall_level+0x137/0x1f0 init/main.c:1375 do_initcalls+0x4b/0x90 init/main.c:1391 kernel_init_freeable+0x3ce/0x560 init/main.c:1615 kernel_init+0x19/0x1b0 init/main.c:1506 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 -> #0 (input_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_interruptible_nested+0x17/0x20 kernel/locking/mutex.c:765 input_register_device+0xb66/0x1140 drivers/input/input.c:2422 steam_input_register+0x9b1/0xc80 drivers/hid/hid-steam.c:469 hid_hw_close+0xa5/0xd0 drivers/hid/hid-core.c:2155 drop_ref drivers/hid/hidraw.c:338 [inline] hidraw_release+0x39d/0x5d0 drivers/hid/hidraw.c:360 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 other info that might help us debug this: Chain exists of: input_mutex --> &dev->mutex#2 --> &hdev->ll_open_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&hdev->ll_open_lock); lock(&dev->mutex#2); lock(&hdev->ll_open_lock); lock(input_mutex); *** DEADLOCK *** 2 locks held by syz.2.380/6075: #0: ffffffff8d0adbe8 (minors_lock){+.+.}-{3:3}, at: hidraw_release+0x71/0x5d0 drivers/hid/hidraw.c:351 #1: ffff888059861ee0 (&hdev->ll_open_lock){+.+.}-{3:3}, at: hid_hw_close+0x2c/0xd0 drivers/hid/hid-core.c:2153 stack backtrace: CPU: 0 PID: 6075 Comm: syz.2.380 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_interruptible_nested+0x17/0x20 kernel/locking/mutex.c:765 input_register_device+0xb66/0x1140 drivers/input/input.c:2422 steam_input_register+0x9b1/0xc80 drivers/hid/hid-steam.c:469 hid_hw_close+0xa5/0xd0 drivers/hid/hid-core.c:2155 drop_ref drivers/hid/hidraw.c:338 [inline] hidraw_release+0x39d/0x5d0 drivers/hid/hidraw.c:360 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f4fe5fdaba9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc5dc26cb8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 0000000000028be8 RCX: 00007f4fe5fdaba9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f4fe6223da0 R08: 0000000000000001 R09: 000000045dc26faf R10: 0000001b31320000 R11: 0000000000000246 R12: 00007f4fe6221fac R13: 00007f4fe6221fa0 R14: ffffffffffffffff R15: 00007ffc5dc26dd0