======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L      
------------------------------------------------------
syz.2.335/6899 is trying to acquire lock:
ffffffff91a50980 (disks_mutex){+.+.}-{4:4}, at: md_alloc+0x3e/0x10c0 drivers/md/md.c:6355

but task is already holding lock:
ffffffff90be3120 (major_names_lock){+.+.}-{4:4}, at: blk_probe_dev+0x28/0x1e0 block/genhd.c:885

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (major_names_lock){+.+.}-{4:4}:
       lock_acquire kernel/locking/lockdep.c:5942 [inline]
       lock_acquire+0x1d1/0x380 kernel/locking/lockdep.c:5899
       __mutex_lock_common kernel/locking/mutex.c:646 [inline]
       __mutex_lock+0x19f/0x1c10 kernel/locking/mutex.c:821
       blk_probe_dev+0x28/0x1e0 block/genhd.c:885
       blk_request_module+0x16/0xc0 block/genhd.c:901
       blkdev_get_no_open+0x9b/0xf0 block/bdev.c:870
       bdev_file_open_by_dev block/bdev.c:1091 [inline]
       bdev_file_open_by_dev+0x70/0x210 block/bdev.c:1079
       md_import_device+0x120/0x360 drivers/md/md.c:3861
       md_add_new_disk+0xdbf/0x1820 drivers/md/md.c:7681
       md_ioctl+0x2c1d/0x3700 drivers/md/md.c:8525
       blkdev_ioctl+0x5ad/0x6f0 block/ioctl.c:798
       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:61 [inline]
       do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&mddev->reconfig_mutex){+.+.}-{4:4}:
       lock_acquire kernel/locking/lockdep.c:5942 [inline]
       lock_acquire+0x1d1/0x380 kernel/locking/lockdep.c:5899
       __mutex_lock_common kernel/locking/mutex.c:646 [inline]
       __mutex_lock+0x19f/0x1c10 kernel/locking/mutex.c:821
       mddev_lock_nointr drivers/md/md.h:734 [inline]
       md_alloc+0x3d0/0x10c0 drivers/md/md.c:6413
       md_alloc_and_put+0x16/0xb0 drivers/md/md.c:6452
       add_named_array+0x27d/0x3a0 drivers/md/md.c:6495
       param_attr_store+0x199/0x300 kernel/params.c:591
       module_attr_store+0x58/0x80 kernel/params.c:906
       sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
       kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
       new_sync_write fs/read_write.c:595 [inline]
       vfs_write+0x6af/0x1050 fs/read_write.c:687
       ksys_write+0x12a/0x250 fs/read_write.c:739
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (disks_mutex){+.+.}-{4:4}:
       check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3209
       check_prevs_add kernel/locking/lockdep.c:3328 [inline]
       validate_chain kernel/locking/lockdep.c:3952 [inline]
       __lock_acquire+0x1528/0x1f40 kernel/locking/lockdep.c:5288
       lock_acquire kernel/locking/lockdep.c:5942 [inline]
       lock_acquire+0x1d1/0x380 kernel/locking/lockdep.c:5899
       __mutex_lock_common kernel/locking/mutex.c:646 [inline]
       __mutex_lock+0x19f/0x1c10 kernel/locking/mutex.c:821
       md_alloc+0x3e/0x10c0 drivers/md/md.c:6355
       md_alloc_and_put drivers/md/md.c:6452 [inline]
       md_probe drivers/md/md.c:6468 [inline]
       md_probe+0x73/0xf0 drivers/md/md.c:6463
       blk_probe_dev+0x149/0x1e0 block/genhd.c:888
       blk_request_module+0x16/0xc0 block/genhd.c:901
       blkdev_get_no_open+0x9b/0xf0 block/bdev.c:870
       blkdev_open+0x141/0x4f0 block/fops.c:677
       do_dentry_open+0x674/0x1470 fs/open.c:1000
       vfs_open_consume+0xcc/0x460 fs/open.c:1131
       do_open fs/namei.c:4845 [inline]
       path_openat+0x1547/0x23f0 fs/namei.c:5010
       do_file_open+0x20e/0x430 fs/namei.c:5039
       do_sys_openat2+0x163/0x1d0 fs/open.c:1442
       do_sys_open fs/open.c:1448 [inline]
       __do_sys_openat fs/open.c:1464 [inline]
       __se_sys_openat fs/open.c:1459 [inline]
       __x64_sys_openat+0x12d/0x210 fs/open.c:1459
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  disks_mutex --> &mddev->reconfig_mutex --> major_names_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(major_names_lock);
                               lock(&mddev->reconfig_mutex);
                               lock(major_names_lock);
  lock(disks_mutex);

 *** DEADLOCK ***

locks held by syz.2.335/6899: 1, last CPU#0:
 #0: ffffffff90be3120 (major_names_lock){+.+.}-{4:4}, at: blk_probe_dev+0x28/0x1e0 block/genhd.c:885

stack backtrace:
CPU: 0 UID: 0 PID: 6899 Comm: syz.2.335 Tainted: G             L       syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_circular_bug.cold+0x178/0x1be kernel/locking/lockdep.c:2087
 check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2219
 check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3209
 check_prevs_add kernel/locking/lockdep.c:3328 [inline]
 validate_chain kernel/locking/lockdep.c:3952 [inline]
 __lock_acquire+0x1528/0x1f40 kernel/locking/lockdep.c:5288
 lock_acquire kernel/locking/lockdep.c:5942 [inline]
 lock_acquire+0x1d1/0x380 kernel/locking/lockdep.c:5899
 __mutex_lock_common kernel/locking/mutex.c:646 [inline]
 __mutex_lock+0x19f/0x1c10 kernel/locking/mutex.c:821
 md_alloc+0x3e/0x10c0 drivers/md/md.c:6355
 md_alloc_and_put drivers/md/md.c:6452 [inline]
 md_probe drivers/md/md.c:6468 [inline]
 md_probe+0x73/0xf0 drivers/md/md.c:6463
 blk_probe_dev+0x149/0x1e0 block/genhd.c:888
 blk_request_module+0x16/0xc0 block/genhd.c:901
 blkdev_get_no_open+0x9b/0xf0 block/bdev.c:870
 blkdev_open+0x141/0x4f0 block/fops.c:677
 do_dentry_open+0x674/0x1470 fs/open.c:1000
 vfs_open_consume+0xcc/0x460 fs/open.c:1131
 do_open fs/namei.c:4845 [inline]
 path_openat+0x1547/0x23f0 fs/namei.c:5010
 do_file_open+0x20e/0x430 fs/namei.c:5039
 do_sys_openat2+0x163/0x1d0 fs/open.c:1442
 do_sys_open fs/open.c:1448 [inline]
 __do_sys_openat fs/open.c:1464 [inline]
 __se_sys_openat fs/open.c:1459 [inline]
 __x64_sys_openat+0x12d/0x210 fs/open.c:1459
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0d36d9f559
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:00007f0d37bed028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0d37025fa0 RCX: 00007f0d36d9f559
RDX: 0000000000000002 RSI: 0000200000000180 RDI: ffffffffffffff9c
RBP: 00007f0d36e36b50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0d37026038 R14: 00007f0d37025fa0 R15: 00007ffc7ea81e78
 </TASK>
md: async del_gendisk mode will be removed in future, please upgrade to mdadm-4.5+
block device autoloading is deprecated and will be removed.