Warning: Permanently added '10.128.0.236' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 75.127285][ T8827] [ 75.129639][ T8827] ====================================================== [ 75.136673][ T8827] WARNING: possible circular locking dependency detected [ 75.143669][ T8827] 5.14.0-rc5-syzkaller #0 Not tainted [ 75.149017][ T8827] ------------------------------------------------------ [ 75.156012][ T8827] systemd-udevd/8827 is trying to acquire lock: [ 75.162404][ T8827] ffffffff8c486b88 (loop_ctl_mutex){+.+.}-{3:3}, at: loop_add+0x9c/0x8c0 [ 75.171042][ T8827] [ 75.171042][ T8827] but task is already holding lock: [ 75.178527][ T8827] ffffffff8c1f3fe8 (major_names_lock){+.+.}-{3:3}, at: blk_request_module+0x25/0x1d0 [ 75.188428][ T8827] [ 75.188428][ T8827] which lock already depends on the new lock. [ 75.188428][ T8827] [ 75.198805][ T8827] [ 75.198805][ T8827] the existing dependency chain (in reverse order) is: [ 75.207791][ T8827] [ 75.207791][ T8827] -> #3 (major_names_lock){+.+.}-{3:3}: [ 75.215499][ T8827] __mutex_lock+0x12a/0x10a0 [ 75.220627][ T8827] __register_blkdev+0x2b/0x3e0 [ 75.225997][ T8827] register_mtd_blktrans+0x85/0x3c0 [ 75.231713][ T8827] do_one_initcall+0x103/0x650 [ 75.236994][ T8827] kernel_init_freeable+0x6b8/0x741 [ 75.242834][ T8827] kernel_init+0x1a/0x1d0 [ 75.247704][ T8827] ret_from_fork+0x1f/0x30 [ 75.252636][ T8827] [ 75.252636][ T8827] -> #2 (mtd_table_mutex){+.+.}-{3:3}: [ 75.260269][ T8827] __mutex_lock+0x12a/0x10a0 [ 75.265374][ T8827] blktrans_open+0x69/0x600 [ 75.270479][ T8827] blkdev_get_whole+0xa1/0x420 [ 75.275757][ T8827] blkdev_get_by_dev.part.0+0x30c/0xdd0 [ 75.281816][ T8827] blkdev_open+0x295/0x300 [ 75.286743][ T8827] do_dentry_open+0x4c8/0x11d0 [ 75.292021][ T8827] path_openat+0x1c23/0x27f0 [ 75.297123][ T8827] do_filp_open+0x1aa/0x400 [ 75.302140][ T8827] do_sys_openat2+0x16d/0x420 [ 75.307332][ T8827] __x64_sys_open+0x119/0x1c0 [ 75.312526][ T8827] do_syscall_64+0x35/0xb0 [ 75.317456][ T8827] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 75.323864][ T8827] [ 75.323864][ T8827] -> #1 (&disk->open_mutex){+.+.}-{3:3}: [ 75.331760][ T8827] __mutex_lock+0x12a/0x10a0 [ 75.336867][ T8827] del_gendisk+0x8b/0x770 [ 75.341714][ T8827] loop_control_ioctl+0x3b5/0x450 [ 75.347343][ T8827] __do_compat_sys_ioctl+0x1c7/0x290 [ 75.353232][ T8827] __do_fast_syscall_32+0x65/0xf0 [ 75.358774][ T8827] do_fast_syscall_32+0x2f/0x70 [ 75.364141][ T8827] entry_SYSENTER_compat_after_hwframe+0x4d/0x5c [ 75.370989][ T8827] [ 75.370989][ T8827] -> #0 (loop_ctl_mutex){+.+.}-{3:3}: [ 75.378537][ T8827] __lock_acquire+0x2a07/0x54a0 [ 75.383900][ T8827] lock_acquire+0x1ab/0x510 [ 75.388914][ T8827] __mutex_lock+0x12a/0x10a0 [ 75.394021][ T8827] loop_add+0x9c/0x8c0 [ 75.398602][ T8827] loop_probe+0x6a/0x80 [ 75.403270][ T8827] blk_request_module+0x111/0x1d0 [ 75.408811][ T8827] blkdev_get_no_open+0x1d5/0x250 [ 75.414350][ T8827] blkdev_get_by_dev.part.0+0x25/0xdd0 [ 75.420337][ T8827] blkdev_open+0x295/0x300 [ 75.425270][ T8827] do_dentry_open+0x4c8/0x11d0 [ 75.430548][ T8827] path_openat+0x1c23/0x27f0 [ 75.435654][ T8827] do_filp_open+0x1aa/0x400 [ 75.440671][ T8827] do_sys_openat2+0x16d/0x420 [ 75.445889][ T8827] __x64_sys_open+0x119/0x1c0 [ 75.451092][ T8827] do_syscall_64+0x35/0xb0 [ 75.456124][ T8827] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 75.462892][ T8827] [ 75.462892][ T8827] other info that might help us debug this: [ 75.462892][ T8827] [ 75.473109][ T8827] Chain exists of: [ 75.473109][ T8827] loop_ctl_mutex --> mtd_table_mutex --> major_names_lock [ 75.473109][ T8827] [ 75.486508][ T8827] Possible unsafe locking scenario: [ 75.486508][ T8827] [ 75.493943][ T8827] CPU0 CPU1 [ 75.499407][ T8827] ---- ---- [ 75.504783][ T8827] lock(major_names_lock); [ 75.509273][ T8827] lock(mtd_table_mutex); [ 75.516197][ T8827] lock(major_names_lock); [ 75.523207][ T8827] lock(loop_ctl_mutex); [ 75.527527][ T8827] [ 75.527527][ T8827] *** DEADLOCK *** [ 75.527527][ T8827] [ 75.535667][ T8827] 1 lock held by systemd-udevd/8827: [ 75.540936][ T8827] #0: ffffffff8c1f3fe8 (major_names_lock){+.+.}-{3:3}, at: blk_request_module+0x25/0x1d0 [ 75.550867][ T8827] [ 75.550867][ T8827] stack backtrace: [ 75.556737][ T8827] CPU: 0 PID: 8827 Comm: systemd-udevd Not tainted 5.14.0-rc5-syzkaller #0 [ 75.565316][ T8827] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 75.575359][ T8827] Call Trace: [ 75.578716][ T8827] dump_stack_lvl+0xcd/0x134 [ 75.583313][ T8827] check_noncircular+0x25f/0x2e0 [ 75.588243][ T8827] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 75.594217][ T8827] ? print_circular_bug+0x1e0/0x1e0 [ 75.599406][ T8827] ? lock_chain_count+0x20/0x20 [ 75.604254][ T8827] ? lockdep_lock+0xc6/0x200 [ 75.608843][ T8827] ? call_rcu_zapped+0xb0/0xb0 [ 75.613609][ T8827] __lock_acquire+0x2a07/0x54a0 [ 75.618457][ T8827] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 75.624442][ T8827] lock_acquire+0x1ab/0x510 [ 75.628987][ T8827] ? loop_add+0x9c/0x8c0 [ 75.633334][ T8827] ? lock_release+0x720/0x720 [ 75.638001][ T8827] ? path_openat+0x1c23/0x27f0 [ 75.642757][ T8827] ? do_filp_open+0x1aa/0x400 [ 75.647430][ T8827] ? do_sys_openat2+0x16d/0x420 [ 75.652280][ T8827] ? __x64_sys_open+0x119/0x1c0 [ 75.657399][ T8827] __mutex_lock+0x12a/0x10a0 [ 75.661993][ T8827] ? loop_add+0x9c/0x8c0 [ 75.666229][ T8827] ? loop_add+0x9c/0x8c0 [ 75.670468][ T8827] ? mutex_lock_io_nested+0xf00/0xf00 [ 75.675926][ T8827] ? rcu_read_lock_sched_held+0x3a/0x70 [ 75.681574][ T8827] loop_add+0x9c/0x8c0 [ 75.685636][ T8827] ? find_inode_fast+0x16f/0x220 [ 75.690572][ T8827] loop_probe+0x6a/0x80 [ 75.694897][ T8827] ? loop_add+0x8c0/0x8c0 [ 75.699222][ T8827] blk_request_module+0x111/0x1d0 [ 75.704252][ T8827] blkdev_get_no_open+0x1d5/0x250 [ 75.709282][ T8827] blkdev_get_by_dev.part.0+0x25/0xdd0 [ 75.714823][ T8827] ? devcgroup_check_permission+0x1bb/0x410 [ 75.720730][ T8827] blkdev_open+0x295/0x300 [ 75.725141][ T8827] do_dentry_open+0x4c8/0x11d0 [ 75.729904][ T8827] ? blkdev_get_by_dev+0x80/0x80 [ 75.734832][ T8827] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 75.741067][ T8827] ? may_open+0x1f6/0x420 [ 75.745390][ T8827] path_openat+0x1c23/0x27f0 [ 75.749985][ T8827] ? path_lookupat+0x860/0x860 [ 75.754835][ T8827] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 75.760991][ T8827] do_filp_open+0x1aa/0x400 [ 75.765491][ T8827] ? may_open_dev+0xf0/0xf0 [ 75.769996][ T8827] ? rwlock_bug.part.0+0x90/0x90 [ 75.774938][ T8827] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 75.781184][ T8827] ? _find_next_bit+0x1e3/0x260 [ 75.786039][ T8827] ? _raw_spin_unlock+0x24/0x40 [ 75.790894][ T8827] ? alloc_fd+0x2f0/0x670 [ 75.795230][ T8827] do_sys_openat2+0x16d/0x420 [ 75.799927][ T8827] ? build_open_flags+0x6f0/0x6f0 [ 75.804952][ T8827] ? __context_tracking_exit+0xb8/0xe0 [ 75.810411][ T8827] __x64_sys_open+0x119/0x1c0 [ 75.815082][ T8827] ? do_sys_open+0x140/0x140 [ 75.819688][ T8827] ? __secure_computing+0x104/0x360 [ 75.824907][ T8827] do_syscall_64+0x35/0xb0 [ 75.829330][ T8827] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 75.835230][ T8827] RIP: 0033:0x7f8a41752840 [ 75.839641][ T8827] Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 [ 75.859248][ T8827] RSP: 002b:00007ffd688d1e98 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 [ 75.867744][ T8827] RAX: ffffffffffffffda RBX: 000055b78830d8f0 RCX: 00007f8a41752840 executing program executing program executing program [ 75.875714][ T8827] RDX: 000055b786885fe3 RSI: 00000000000a0800 RDI: 000055b78830d830 [ 75.883678][ T8827] RBP: 00007ffd688d2010 R08: 000055b786885670 R09: 0000000000000010 [ 75.891642][ T8827] R10: 000055b786885d0c R11: 0000000000000246 R12: 00007ffd688d1f60 [ 75.899613][ T8827] R13: 000055b78830f010 R14: 0000000000000003 R15: 000000000000000e executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program