======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.8.1057/8791 is trying to acquire lock:
ffffffff8d70f3a8 (major_names_lock){+.+.}-{3:3}, at: blk_probe_dev block/genhd.c:689 [inline]
ffffffff8d70f3a8 (major_names_lock){+.+.}-{3:3}, at: blk_request_module+0x31/0x290 block/genhd.c:705
but task is already holding lock:
ffff88807b1502c0 (&mddev->reconfig_mutex){+.+.}-{3:3}, at: mddev_lock drivers/md/md.h:543 [inline]
ffff88807b1502c0 (&mddev->reconfig_mutex){+.+.}-{3:3}, at: new_dev_store+0x222/0x660 drivers/md/md.c:4671
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (&mddev->reconfig_mutex){+.+.}-{3:3}:
__mutex_lock_common+0x1e5/0x2400 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_interruptible_nested+0x17/0x20 kernel/locking/mutex.c:765
mddev_lock drivers/md/md.h:543 [inline]
new_dev_store+0x222/0x660 drivers/md/md.c:4671
md_attr_store+0xdd/0x130 drivers/md/md.c:5643
kernfs_fop_write_iter+0x3a8/0x500 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2179 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x748/0xd70 fs/read_write.c:594
ksys_write+0x153/0x260 fs/read_write.c:647
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
-> #3 (kn->active#827){++++}-{0:0}:
kernfs_drain fs/kernfs/dir.c:478 [inline]
__kernfs_remove+0x5da/0xcb0 fs/kernfs/dir.c:1372
kernfs_remove+0x1d/0x30 fs/kernfs/dir.c:1406
__kobject_del+0xe0/0x2e0 lib/kobject.c:628
kobject_del+0x41/0x60 lib/kobject.c:651
mddev_delayed_delete+0x27/0x30 drivers/md/md.c:5685
process_one_work+0x867/0xff0 kernel/workqueue.c:2310
worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
-> #2 ((work_completion)(&mddev->del_work)){+.+.}-{0:0}:
process_one_work+0x7ba/0xff0 kernel/workqueue.c:2286
worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
-> #1 ((wq_completion)md_misc){+.+.}-{0:0}:
flush_workqueue+0x16a/0x1390 kernel/workqueue.c:2830
md_alloc+0x2e/0xc10 drivers/md/md.c:5727
blk_probe_dev block/genhd.c:692 [inline]
blk_request_module+0x26e/0x290 block/genhd.c:-1
blkdev_get_no_open+0x38/0x1d0 block/bdev.c:736
blkdev_get_by_dev+0x77/0xa50 block/bdev.c:803
blkdev_open+0x128/0x2c0 block/fops.c:466
do_dentry_open+0x7f7/0xf90 fs/open.c:826
do_open fs/namei.c:3659 [inline]
path_openat+0x2718/0x2fb0 fs/namei.c:3793
do_filp_open+0x1df/0x400 fs/namei.c:3820
do_sys_openat2+0x14b/0x500 fs/open.c:1255
do_sys_open fs/open.c:1271 [inline]
__do_sys_openat fs/open.c:1287 [inline]
__se_sys_openat fs/open.c:1282 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1282
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
-> #0 (major_names_lock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3120 [inline]
check_prevs_add kernel/locking/lockdep.c:3239 [inline]
validate_chain kernel/locking/lockdep.c:3855 [inline]
__lock_acquire+0x38f7/0x7d40 kernel/locking/lockdep.c:5120
lock_acquire+0x19f/0x400 kernel/locking/lockdep.c:5737
__mutex_lock_common+0x1e5/0x2400 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
blk_probe_dev block/genhd.c:689 [inline]
blk_request_module+0x31/0x290 block/genhd.c:705
blkdev_get_no_open+0x38/0x1d0 block/bdev.c:736
blkdev_get_by_dev+0x77/0xa50 block/bdev.c:803
lock_rdev drivers/md/md.c:2583 [inline]
md_import_device+0x3e2/0x810 drivers/md/md.c:3781
new_dev_store+0x38d/0x660 drivers/md/md.c:-1
md_attr_store+0xdd/0x130 drivers/md/md.c:5643
kernfs_fop_write_iter+0x3a8/0x500 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2179 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x748/0xd70 fs/read_write.c:594
ksys_write+0x153/0x260 fs/read_write.c:647
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
other info that might help us debug this:
Chain exists of:
major_names_lock --> kn->active#827
--> &mddev->reconfig_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&mddev->reconfig_mutex);
lock(kn->active
#827
);
lock(
&mddev->reconfig_mutex
);
lock(
major_names_lock);
*** DEADLOCK ***
5 locks held by syz.8.1057/8791:
#0: ffff88801c3be5f0
(&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2bf/0x370 fs/file.c:1056
#1: ffff88807edd6460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590
#2: ffff888060565c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287
#3:
ffff88802069cae8
(kn->active
#827){++++}-{0:0}, at: kernfs_fop_write_iter+0x1fd/0x500 fs/kernfs/file.c:288
#4: ffff88807b1502c0 (&mddev->reconfig_mutex){+.+.}-{3:3}
, at: mddev_lock drivers/md/md.h:543 [inline]
, at: new_dev_store+0x222/0x660 drivers/md/md.c:4671
stack backtrace:
CPU: 0 PID: 8791 Comm: syz.8.1057 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
check_noncircular+0x2f8/0x400 kernel/locking/lockdep.c:2178
check_prev_add kernel/locking/lockdep.c:3120 [inline]
check_prevs_add kernel/locking/lockdep.c:3239 [inline]
validate_chain kernel/locking/lockdep.c:3855 [inline]
__lock_acquire+0x38f7/0x7d40 kernel/locking/lockdep.c:5120
lock_acquire+0x19f/0x400 kernel/locking/lockdep.c:5737
__mutex_lock_common+0x1e5/0x2400 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
blk_probe_dev block/genhd.c:689 [inline]
blk_request_module+0x31/0x290 block/genhd.c:705
blkdev_get_no_open+0x38/0x1d0 block/bdev.c:736
blkdev_get_by_dev+0x77/0xa50 block/bdev.c:803
lock_rdev drivers/md/md.c:2583 [inline]
md_import_device+0x3e2/0x810 drivers/md/md.c:3781
new_dev_store+0x38d/0x660 drivers/md/md.c:-1
md_attr_store+0xdd/0x130 drivers/md/md.c:5643
kernfs_fop_write_iter+0x3a8/0x500 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2179 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x748/0xd70 fs/read_write.c:594
ksys_write+0x153/0x260 fs/read_write.c:647
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
RIP: 0033:0x7f9a2f109559
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:00007f9a2d360028 EFLAGS: 00000246
ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f9a2f38ffa0 RCX: 00007f9a2f109559
RDX: 0000000000000016 RSI: 0000200000000280 RDI: 0000000000000006
RBP: 00007f9a2f1a0b20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9a2f390038 R14: 00007f9a2f38ffa0 R15: 00007ffe262eea58
debugfs: creating file 'ram16'
device: 'ram16': device_add
kobject: 'ram16' (ffff888017c7de40): kobject_add_internal: parent: 'block', set: 'devices'
block ram16: No ACPI support
PM: Adding info for No Bus:ram16
kobject: 'ram16' (ffff888017c7de40): kobject_uevent_env
kobject: 'ram16' (ffff888017c7de40): kobject_uevent_env: uevent_suppress caused the event to drop!
kobject: 'holders' (ffff88801f2b2180): kobject_add_internal: parent: 'ram16', set: ''
kobject: 'slaves' (ffff888060314100): kobject_add_internal: parent: 'ram16', set: ''
kobject: 'queue' (ffff888024328ef8): kobject_add_internal: parent: 'ram16', set: ''
debugfs: creating file 'ram16'
kobject: 'queue' (ffff888024328ef8): kobject_uevent_env
kobject: 'queue' (ffff888024328ef8): kobject_uevent_env: filter function caused the event to drop!
device: '1:16': device_add
kobject: '1:16' (ffff8880599a0000): kobject_add_internal: parent: 'bdi', set: 'devices'
bdi 1:16: No ACPI support
PM: Adding info for No Bus:1:16
kobject: '1:16' (ffff8880599a0000): kobject_uevent_env
kobject: '1:16' (ffff8880599a0000): fill_kobj_path: path = '/devices/virtual/bdi/1:16'
debugfs: creating file '1:16'
debugfs: creating file 'stats'
kobject: 'ram16' (ffff888017c7de40): kobject_uevent_env
kobject: 'ram16' (ffff888017c7de40): fill_kobj_path: path = '/devices/virtual/block/ram16'
block device autoloading is deprecated and will be removed.
md: bind
kobject: 'dev-ram16' (ffff88802682a878): kobject_add_internal: parent: 'md', set: ''
kcov: kcov_task_exit: t = ffff88802d343b80, kcov->t = ffff88802d343b80