program: 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") ioctl(r1, 0x40140921, &(0x7f0000000420)="0100000001000000010000000100000006") ioctl(r1, 0x400c0930, 0x0) ioctl(r1, 0x40140921, &(0x7f0000000440)) [ 103.147813][ T4644] Bluetooth: hci0: command tx timeout [ 103.282340][ T5322] md: async del_gendisk mode will be removed in future, please upgrade to mdadm-4.5+ [ 103.293955][ T5323] md: async del_gendisk mode will be removed in future, please upgrade to mdadm-4.5+ [ 103.294085][ T5323] block device autoloading is deprecated and will be removed. [ 103.377614][ T5322] md/raid10:md0: not clean -- starting background reconstruction [ 103.377626][ T5322] md/raid10:md0: active with 1 out of 2 devices [ 103.390168][ T5322] md0: detected capacity change from 0 to 2048 [ 103.402399][ T5323] [ 103.406423][ T5323] ====================================================== [ 103.409640][ T5323] WARNING: possible circular locking dependency detected [ 103.412826][ T5323] syzkaller #0 Not tainted [ 103.415144][ T5323] ------------------------------------------------------ [ 103.418839][ T5323] syz.0.0/5323 is trying to acquire lock: [ 103.422105][ T5323] ffffffff8f556d00 (major_names_lock){+.+.}-{4:4}, at: blk_request_module+0x35/0x2a0 [ 103.426495][ T5323] [ 103.426495][ T5323] but task is already holding lock: [ 103.429811][ T5323] ffff888038eb2358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: mddev_suspend_and_lock+0x48/0xf0 [ 103.434513][ T5323] [ 103.434513][ T5323] which lock already depends on the new lock. [ 103.434513][ T5323] [ 103.439538][ T5323] [ 103.439538][ T5323] the existing dependency chain (in reverse order) is: [ 103.443615][ T5323] [ 103.443615][ T5323] -> #3 (&mddev->reconfig_mutex){+.+.}-{4:4}: [ 103.447219][ T5323] __mutex_lock+0x19d/0x1550 [ 103.449777][ T5323] md_start_sync+0x179/0x1010 [ 103.452668][ T5323] process_scheduled_works+0xc3d/0x1630 [ 103.455927][ T5323] worker_thread+0xa47/0xfb0 [ 103.458249][ T5323] kthread+0x38b/0x480 [ 103.460154][ T5323] ret_from_fork+0x514/0xb70 [ 103.462408][ T5323] ret_from_fork_asm+0x1a/0x30 [ 103.464550][ T5323] [ 103.464550][ T5323] -> #2 ((work_completion)(&mddev->sync_work)){+.+.}-{0:0}: [ 103.468547][ T5323] process_scheduled_works+0xc03/0x1630 [ 103.471185][ T5323] worker_thread+0xa47/0xfb0 [ 103.473522][ T5323] kthread+0x38b/0x480 [ 103.475578][ T5323] ret_from_fork+0x514/0xb70 [ 103.478063][ T5323] ret_from_fork_asm+0x1a/0x30 [ 103.480762][ T5323] [ 103.480762][ T5323] -> #1 ((wq_completion)md_misc){+.+.}-{0:0}: [ 103.484244][ T5323] touch_wq_lockdep_map+0xcb/0x180 [ 103.487168][ T5323] __flush_workqueue+0x148/0x1470 [ 103.489597][ T5323] md_alloc+0x32/0xf20 [ 103.492114][ T5323] md_alloc_and_put+0x1a/0x1f0 [ 103.494544][ T5323] blk_request_module+0x27d/0x2a0 [ 103.497018][ T5323] blkdev_get_no_open+0x3f/0xe0 [ 103.499418][ T5323] blkdev_open+0x1d7/0x600 [ 103.501715][ T5323] do_dentry_open+0x816/0x1380 [ 103.503964][ T5323] vfs_open+0x3b/0x340 [ 103.505926][ T5323] path_openat+0x1443/0x1d60 [ 103.508169][ T5323] do_file_open+0x23e/0x4a0 [ 103.510339][ T5323] do_sys_openat2+0x115/0x200 [ 103.512482][ T5323] __x64_sys_openat+0x138/0x170 [ 103.515598][ T5323] do_syscall_64+0x166/0x520 [ 103.517616][ T5323] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 103.520229][ T5323] [ 103.520229][ T5323] -> #0 (major_names_lock){+.+.}-{4:4}: [ 103.523494][ T5323] __lock_acquire+0x164c/0x2de0 [ 103.525688][ T5323] lock_acquire+0x115/0x350 [ 103.527852][ T5323] __mutex_lock+0x19d/0x1550 [ 103.530092][ T5323] blk_request_module+0x35/0x2a0 [ 103.532402][ T5323] blkdev_get_no_open+0x3f/0xe0 [ 103.534660][ T5323] bdev_file_open_by_dev+0xa0/0x240 [ 103.537031][ T5323] md_import_device+0x2e9/0x650 [ 103.539291][ T5323] md_add_new_disk+0x669/0x1850 [ 103.541659][ T5323] md_ioctl+0x200a/0x2610 [ 103.543702][ T5323] blkdev_ioctl+0x5e3/0x740 [ 103.545851][ T5323] __se_sys_ioctl+0xfc/0x170 [ 103.548056][ T5323] do_syscall_64+0x166/0x520 [ 103.550327][ T5323] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 103.553140][ T5323] [ 103.553140][ T5323] other info that might help us debug this: [ 103.553140][ T5323] [ 103.557543][ T5323] Chain exists of: [ 103.557543][ T5323] major_names_lock --> (work_completion)(&mddev->sync_work) --> &mddev->reconfig_mutex [ 103.557543][ T5323] [ 103.564294][ T5323] Possible unsafe locking scenario: [ 103.564294][ T5323] [ 103.567358][ T5323] CPU0 CPU1 [ 103.569610][ T5323] ---- ---- [ 103.572122][ T5323] lock(&mddev->reconfig_mutex); [ 103.574294][ T5323] lock((work_completion)(&mddev->sync_work)); [ 103.577987][ T5323] lock(&mddev->reconfig_mutex); [ 103.581122][ T5323] lock(major_names_lock); [ 103.582958][ T5323] [ 103.582958][ T5323] *** DEADLOCK *** [ 103.582958][ T5323] [ 103.586338][ T5323] locks held by syz.0.0/5323: 1, last CPU#0: [ 103.588870][ T5323] #0: ffff888038eb2358 (&mddev->reconfig_mutex){+.+.}-{4:4}, at: mddev_suspend_and_lock+0x48/0xf0 [ 103.593928][ T5323] [ 103.593928][ T5323] stack backtrace: [ 103.596564][ T5323] CPU: 0 UID: 0 PID: 5323 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 103.600746][ T5323] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 103.605294][ T5323] Call Trace: [ 103.606803][ T5323] [ 103.608165][ T5323] dump_stack_lvl+0xe8/0x150 [ 103.610198][ T5323] print_circular_bug+0x2e2/0x300 [ 103.612416][ T5323] check_noncircular+0x12f/0x150 [ 103.614744][ T5323] __lock_acquire+0x164c/0x2de0 [ 103.616866][ T5323] ? post_alloc_hook+0x208/0x250 [ 103.618887][ T5323] ? get_page_from_freelist+0x2209/0x2280 [ 103.621056][ T5323] lock_acquire+0x115/0x350 [ 103.623087][ T5323] ? blk_request_module+0x35/0x2a0 [ 103.625415][ T5323] __mutex_lock+0x19d/0x1550 [ 103.627518][ T5323] ? blk_request_module+0x35/0x2a0 [ 103.629823][ T5323] ? lock_acquire+0x115/0x350 [ 103.631991][ T5323] ? blk_request_module+0x35/0x2a0 [ 103.634282][ T5323] ? __pfx___mutex_lock+0x10/0x10 [ 103.636737][ T5323] ? find_inode_fast+0x5dc/0x740 [ 103.638871][ T5323] ? find_inode_fast+0xd2/0x740 [ 103.640982][ T5323] blk_request_module+0x35/0x2a0 [ 103.643148][ T5323] blkdev_get_no_open+0x3f/0xe0 [ 103.645254][ T5323] bdev_file_open_by_dev+0xa0/0x240 [ 103.647441][ T5323] md_import_device+0x2e9/0x650 [ 103.649682][ T5323] md_add_new_disk+0x669/0x1850 [ 103.651824][ T5323] md_ioctl+0x200a/0x2610 [ 103.653775][ T5323] ? tomoyo_path_number_perm+0x219/0x5f0 [ 103.656208][ T5323] ? __pfx_md_ioctl+0x10/0x10 [ 103.658317][ T5323] ? do_vfs_ioctl+0x116f/0x1530 [ 103.661004][ T5323] ? __pfx_do_vfs_ioctl+0x10/0x10 [ 103.663761][ T5323] ? hook_file_ioctl+0x1f2/0x600 [ 103.666455][ T5323] ? __pfx_md_ioctl+0x10/0x10 [ 103.668516][ T5323] blkdev_ioctl+0x5e3/0x740 [ 103.670362][ T5323] ? __pfx_blkdev_ioctl+0x10/0x10 [ 103.672406][ T5323] ? __fget_files+0x2a/0x420 [ 103.674318][ T5323] ? bpf_lsm_file_ioctl+0x9/0x20 [ 103.676294][ T5323] ? __pfx_blkdev_ioctl+0x10/0x10 [ 103.678379][ T5323] __se_sys_ioctl+0xfc/0x170 [ 103.680259][ T5323] do_syscall_64+0x166/0x520 [ 103.682280][ T5323] ? trace_irq_disable+0x3b/0x140 [ 103.684502][ T5323] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 103.687121][ T5323] ? clear_bhb_loop+0x70/0xc0 [ 103.689039][ T5323] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 103.691497][ T5323] RIP: 0033:0x7fec3759e159 [ 103.693467][ T5323] 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 [ 103.701774][ T5323] RSP: 002b:00007fec384c6fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 103.705468][ T5323] RAX: ffffffffffffffda RBX: 00007fec37826090 RCX: 00007fec3759e159 [ 103.708827][ T5323] RDX: 0000200000000440 RSI: 0000000040140921 RDI: 0000000000000004 [ 103.712265][ T5323] RBP: 00007fec3763506b R08: 0000000000000000 R09: 0000000000000000 [ 103.715495][ T5323] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 103.718836][ T5323] R13: 00007fec37826128 R14: 00007fec37826090 R15: 00007ffe88146718 [ 103.722292][ T5323] [ 103.734110][ T5327] md: resync of RAID array md0 [ 103.752944][ T5327] md: md0: resync done. [ 103.804585][ T5323] md: could not open device unknown-block(0,0). [ 103.804622][ T5323] md: md_import_device returned -6