====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.9.2723/18830 is trying to acquire lock: ffffffff8f793ce0 (major_names_lock){+.+.}-{4:4}, at: blk_probe_dev+0x28/0x1e0 block/genhd.c:877 but task is already holding lock: ffff888050068358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: mddev_lock drivers/md/md.h:714 [inline] ffff888050068358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: mddev_suspend_and_lock drivers/md/md.h:1012 [inline] ffff888050068358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: mddev_suspend_and_lock drivers/md/md.h:1004 [inline] ffff888050068358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: md_ioctl+0x112d/0x36b0 drivers/md/md.c:8378 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&mddev->reconfig_mutex){+.+.}-{4:4}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x1a4/0x1bd0 kernel/locking/mutex.c:821 mddev_lock_nointr drivers/md/md.h:735 [inline] md_start_sync+0x79/0xbe0 drivers/md/md.c:10190 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #2 ((work_completion)(&mddev->sync_work)){+.+.}-{0:0}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 process_one_work+0x98e/0x1940 kernel/workqueue.c:3298 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #1 ((wq_completion)md_misc){+.+.}-{0:0}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 touch_wq_lockdep_map+0xad/0x1c0 kernel/workqueue.c:4037 __flush_workqueue+0x131/0x1200 kernel/workqueue.c:4079 md_alloc+0x30/0x10a0 drivers/md/md.c:6313 md_alloc_and_put drivers/md/md.c:6402 [inline] md_probe drivers/md/md.c:6418 [inline] md_probe+0x73/0xf0 drivers/md/md.c:6413 blk_probe_dev+0x149/0x1e0 block/genhd.c:880 blk_request_module+0x16/0xc0 block/genhd.c:893 blkdev_get_no_open+0x9b/0xf0 block/bdev.c:828 blkdev_open+0x141/0x4f0 block/fops.c:663 do_dentry_open+0x6ab/0x14d0 fs/open.c:947 vfs_open+0x82/0x3f0 fs/open.c:1052 do_open fs/namei.c:4700 [inline] path_openat+0x2873/0x4280 fs/namei.c:4863 do_file_open+0x20e/0x430 fs/namei.c:4892 do_sys_openat2+0x10f/0x1e0 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (major_names_lock){+.+.}-{4:4}: check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3165 check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x136c/0x1a40 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x1a4/0x1bd0 kernel/locking/mutex.c:821 blk_probe_dev+0x28/0x1e0 block/genhd.c:877 blk_request_module+0x16/0xc0 block/genhd.c:893 blkdev_get_no_open+0x9b/0xf0 block/bdev.c:828 bdev_file_open_by_dev block/bdev.c:1049 [inline] bdev_file_open_by_dev+0x70/0x210 block/bdev.c:1037 md_import_device+0x120/0x360 drivers/md/md.c:3845 md_add_new_disk+0xcc0/0x1820 drivers/md/md.c:7530 md_ioctl+0x2b28/0x36b0 drivers/md/md.c:8476 blkdev_ioctl+0x5ad/0x6f0 block/ioctl.c:797 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: major_names_lock --> (work_completion)(&mddev->sync_work) --> &mddev->reconfig_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mddev->reconfig_mutex); lock((work_completion)(&mddev->sync_work)); lock(&mddev->reconfig_mutex); lock(major_names_lock); *** DEADLOCK *** 1 lock held by syz.9.2723/18830: #0: ffff888050068358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: mddev_lock drivers/md/md.h:714 [inline] #0: ffff888050068358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: mddev_suspend_and_lock drivers/md/md.h:1012 [inline] #0: ffff888050068358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: mddev_suspend_and_lock drivers/md/md.h:1004 [inline] #0: ffff888050068358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: md_ioctl+0x112d/0x36b0 drivers/md/md.c:8378 stack backtrace: CPU: 0 UID: 0 PID: 18830 Comm: syz.9.2723 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043 check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2175 check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3165 check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x136c/0x1a40 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x1a4/0x1bd0 kernel/locking/mutex.c:821 blk_probe_dev+0x28/0x1e0 block/genhd.c:877 blk_request_module+0x16/0xc0 block/genhd.c:893 blkdev_get_no_open+0x9b/0xf0 block/bdev.c:828 bdev_file_open_by_dev block/bdev.c:1049 [inline] bdev_file_open_by_dev+0x70/0x210 block/bdev.c:1037 md_import_device+0x120/0x360 drivers/md/md.c:3845 md_add_new_disk+0xcc0/0x1820 drivers/md/md.c:7530 md_ioctl+0x2b28/0x36b0 drivers/md/md.c:8476 blkdev_ioctl+0x5ad/0x6f0 block/ioctl.c:797 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1dea79de99 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1deb6b0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f1deaa26180 RCX: 00007f1dea79de99 RDX: 0000200000001600 RSI: 0000000040140921 RDI: 000000000000000c RBP: 00007f1dea833eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1deaa26218 R14: 00007f1deaa26180 R15: 00007ffcbbaa0f18 md: could not open device unknown-block(0,0). md: md_import_device returned -6