program: io_uring_setup(0x70fa, &(0x7f0000000440)={0x0, 0x4ef1, 0x4000, 0x400001, 0x2e0}) mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000040)='./sys\x00', &(0x7f0000000080)='sysfs\x00', 0x0, 0x0) mkdirat(0xffffffffffffff9c, &(0x7f00000000c0)='./dev\x00', 0x1ff) mount(0x0, &(0x7f0000000100)='./dev\x00', &(0x7f0000000140)='devtmpfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000180)='./sys/module/md_mod/parameters/new_array\x00', 0x1, 0x0) write(r0, &(0x7f0000000200)='md0', 0x3) r1 = openat(0xffffffffffffff9c, &(0x7f0000000300)='./dev/md0\x00', 0x105042, 0x0) ioctl(r1, 0x40480923, &(0x7f0000000380)="000000000000000000000000000000000a000000000400000200000002000000000000000100000000000000000000000000000000000000000000000000000002010000000001") r2 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000100), 0xa400, 0x0) r3 = ioctl$KVM_CREATE_VM(r2, 0xae01, 0x0) ioctl$KVM_SET_USER_MEMORY_REGION(r3, 0x4020ae46, &(0x7f0000000080)={0x26e8, 0x0, 0x100000, 0x2000, &(0x7f0000ffe000/0x2000)=nil}) ioctl$KVM_CREATE_DEVICE(r3, 0xc018aec0, &(0x7f00000001c0)={0x1}) ioctl(r1, 0x40140921, &(0x7f0000000420)="0100000001000000010000000100000006") ioctl(r1, 0x400c0930, 0x0) ioctl(r1, 0x40140921, &(0x7f0000000440)="020000000100") [ 81.453000][ T4648] Bluetooth: hci0: command tx timeout [ 81.518852][ T5314] md: async del_gendisk mode will be removed in future, please upgrade to mdadm-4.5+ [ 81.530831][ T5315] md: async del_gendisk mode will be removed in future, please upgrade to mdadm-4.5+ [ 81.530969][ T5315] block device autoloading is deprecated and will be removed. [ 81.645053][ T5314] md/raid10:md0: not clean -- starting background reconstruction [ 81.645069][ T5314] md/raid10:md0: active with 1 out of 2 devices [ 81.646263][ T5314] md0: detected capacity change from 0 to 2048 [ 81.684515][ T5315] block device autoloading is deprecated and will be removed. [ 81.690549][ T5312] [ 81.691640][ T5312] ====================================================== [ 81.694577][ T5312] WARNING: possible circular locking dependency detected [ 81.697549][ T5312] syzkaller #0 Not tainted [ 81.699515][ T5312] ------------------------------------------------------ [ 81.702516][ T5312] kworker/0:6/5312 is trying to acquire lock: [ 81.704913][ T5312] ffff888012d98358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: md_start_sync+0x15a/0x1010 [ 81.709845][ T5312] [ 81.709845][ T5312] but task is already holding lock: [ 81.712971][ T5312] ffffc9000e30fc40 ((work_completion)(&mddev->sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 [ 81.718061][ T5312] [ 81.718061][ T5312] which lock already depends on the new lock. [ 81.718061][ T5312] [ 81.722464][ T5312] [ 81.722464][ T5312] the existing dependency chain (in reverse order) is: [ 81.726405][ T5312] [ 81.726405][ T5312] -> #3 ((work_completion)(&mddev->sync_work)){+.+.}-{0:0}: [ 81.730453][ T5312] process_scheduled_works+0xc03/0x1630 [ 81.733129][ T5312] worker_thread+0xa47/0xfb0 [ 81.735422][ T5312] kthread+0x38b/0x480 [ 81.737425][ T5312] ret_from_fork+0x514/0xb70 [ 81.739570][ T5312] ret_from_fork_asm+0x1a/0x30 [ 81.741832][ T5312] [ 81.741832][ T5312] -> #2 ((wq_completion)md_misc){+.+.}-{0:0}: [ 81.745427][ T5312] touch_wq_lockdep_map+0xcb/0x180 [ 81.747955][ T5312] __flush_workqueue+0x148/0x1470 [ 81.750535][ T5312] md_alloc+0x32/0xf20 [ 81.752492][ T5312] md_alloc_and_put+0x1a/0x1f0 [ 81.754828][ T5312] blk_request_module+0x27d/0x2a0 [ 81.757311][ T5312] blkdev_get_no_open+0x3f/0xe0 [ 81.759686][ T5312] blkdev_open+0x1d7/0x600 [ 81.761920][ T5312] do_dentry_open+0x816/0x1380 [ 81.764263][ T5312] vfs_open+0x3b/0x340 [ 81.766256][ T5312] path_openat+0x1443/0x1d60 [ 81.768274][ T5312] do_file_open+0x23e/0x4a0 [ 81.770541][ T5312] do_sys_openat2+0x115/0x200 [ 81.772821][ T5312] __x64_sys_openat+0x138/0x170 [ 81.775278][ T5312] do_syscall_64+0x166/0x520 [ 81.777472][ T5312] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 81.780065][ T5312] [ 81.780065][ T5312] -> #1 (major_names_lock){+.+.}-{4:4}: [ 81.783352][ T5312] __mutex_lock+0x19d/0x1550 [ 81.785583][ T5312] blk_request_module+0x35/0x2a0 [ 81.787945][ T5312] blkdev_get_no_open+0x3f/0xe0 [ 81.790358][ T5312] bdev_file_open_by_dev+0xa0/0x240 [ 81.792797][ T5312] md_import_device+0x2e9/0x650 [ 81.795316][ T5312] md_add_new_disk+0x669/0x1850 [ 81.799251][ T5312] md_ioctl+0x200a/0x2610 [ 81.801395][ T5312] blkdev_ioctl+0x5e3/0x740 [ 81.803677][ T5312] __se_sys_ioctl+0xfc/0x170 [ 81.805972][ T5312] do_syscall_64+0x166/0x520 [ 81.808226][ T5312] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 81.811028][ T5312] [ 81.811028][ T5312] -> #0 (&mddev->reconfig_mutex){+.+.}-{4:4}: [ 81.814565][ T5312] __lock_acquire+0x164c/0x2de0 [ 81.816841][ T5312] lock_acquire+0x115/0x350 [ 81.818901][ T5312] __mutex_lock+0x19d/0x1550 [ 81.821024][ T5312] md_start_sync+0x15a/0x1010 [ 81.823418][ T5312] process_scheduled_works+0xc3d/0x1630 [ 81.826385][ T5312] worker_thread+0xa47/0xfb0 [ 81.828837][ T5312] kthread+0x38b/0x480 [ 81.831124][ T5312] ret_from_fork+0x514/0xb70 [ 81.833444][ T5312] ret_from_fork_asm+0x1a/0x30 [ 81.835681][ T5312] [ 81.835681][ T5312] other info that might help us debug this: [ 81.835681][ T5312] [ 81.839914][ T5312] Chain exists of: [ 81.839914][ T5312] &mddev->reconfig_mutex --> (wq_completion)md_misc --> (work_completion)(&mddev->sync_work) [ 81.839914][ T5312] [ 81.846708][ T5312] Possible unsafe locking scenario: [ 81.846708][ T5312] [ 81.849822][ T5312] CPU0 CPU1 [ 81.852001][ T5312] ---- ---- [ 81.854237][ T5312] lock((work_completion)(&mddev->sync_work)); [ 81.857026][ T5312] lock((wq_completion)md_misc); [ 81.860276][ T5312] lock((work_completion)(&mddev->sync_work)); [ 81.864086][ T5312] lock(&mddev->reconfig_mutex); [ 81.866353][ T5312] [ 81.866353][ T5312] *** DEADLOCK *** [ 81.866353][ T5312] [ 81.869943][ T5312] locks held by kworker/0:6/5312: 2, last CPU#0: [ 81.872723][ T5312] #0: ffff88801f77ad40 ((wq_completion)md_misc){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 [ 81.877486][ T5312] #1: ffffc9000e30fc40 ((work_completion)(&mddev->sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 [ 81.882733][ T5312] [ 81.882733][ T5312] stack backtrace: [ 81.885364][ T5312] CPU: 0 UID: 0 PID: 5312 Comm: kworker/0:6 Not tainted syzkaller #0 PREEMPT(full) [ 81.889173][ T5312] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 81.893498][ T5312] Workqueue: md_misc md_start_sync [ 81.895834][ T5312] Call Trace: [ 81.897308][ T5312] [ 81.898688][ T5312] dump_stack_lvl+0xe8/0x150 [ 81.900760][ T5312] print_circular_bug+0x2e2/0x300 [ 81.903100][ T5312] check_noncircular+0x12f/0x150 [ 81.905279][ T5312] __lock_acquire+0x164c/0x2de0 [ 81.907364][ T5312] ? rcu_is_watching+0x16/0xb0 [ 81.909409][ T5312] ? mddev_suspend+0x5f4/0x6f0 [ 81.911436][ T5312] lock_acquire+0x115/0x350 [ 81.913468][ T5312] ? md_start_sync+0x15a/0x1010 [ 81.915647][ T5312] __mutex_lock+0x19d/0x1550 [ 81.917918][ T5312] ? md_start_sync+0x15a/0x1010 [ 81.920071][ T5312] ? mddev_suspend+0x5f4/0x6f0 [ 81.922133][ T5312] ? md_start_sync+0x15a/0x1010 [ 81.924272][ T5312] ? __pfx___mutex_lock+0x10/0x10 [ 81.926535][ T5312] ? md_spares_need_change+0x1c/0x240 [ 81.928848][ T5312] ? md_spares_need_change+0x1c/0x240 [ 81.931208][ T5312] md_start_sync+0x15a/0x1010 [ 81.933211][ T5312] ? lock_acquire+0x115/0x350 [ 81.935276][ T5312] ? __pfx_md_start_sync+0x10/0x10 [ 81.937510][ T5312] ? rcu_is_watching+0x16/0xb0 [ 81.939637][ T5312] ? process_scheduled_works+0x97a/0x1630 [ 81.942209][ T5312] process_scheduled_works+0xc3d/0x1630 [ 81.944678][ T5312] ? __pfx_process_scheduled_works+0x10/0x10 [ 81.947306][ T5312] ? assign_work+0x3cf/0x5d0 [ 81.949306][ T5312] worker_thread+0xa47/0xfb0 [ 81.951363][ T5312] ? __kthread_parkme+0x71/0x1f0 [ 81.953485][ T5312] kthread+0x38b/0x480 [ 81.955270][ T5312] ? __pfx_worker_thread+0x10/0x10 [ 81.957461][ T5312] ? __pfx_kthread+0x10/0x10 [ 81.959580][ T5312] ret_from_fork+0x514/0xb70 [ 81.961951][ T5312] ? __pfx_ret_from_fork+0x10/0x10 [ 81.964405][ T5312] ? __switch_to+0xc89/0x1420 [ 81.966466][ T5312] ? __pfx_kthread+0x10/0x10 [ 81.968489][ T5312] ret_from_fork_asm+0x1a/0x30 [ 81.970605][ T5312]