------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(depth <= 0) WARNING: CPU: 1 PID: 27623 at kernel/locking/lockdep.c:3595 __lock_release kernel/locking/lockdep.c:3595 [inline] WARNING: CPU: 1 PID: 27623 at kernel/locking/lockdep.c:3595 lock_release+0x740/0xa10 kernel/locking/lockdep.c:3863 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 27623 Comm: syz-executor5 Not tainted 4.20.0-rc1-next-20181109+ #110 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 panic+0x2ad/0x55c kernel/panic.c:188 __warn.cold.8+0x20/0x45 kernel/panic.c:540 report_bug+0x254/0x2d0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:290 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:969 RIP: 0010:__lock_release kernel/locking/lockdep.c:3595 [inline] RIP: 0010:lock_release+0x740/0xa10 kernel/locking/lockdep.c:3863 Code: 03 38 d0 7c 08 84 d2 0f 85 da 02 00 00 8b 35 a7 95 b3 08 85 f6 75 15 48 c7 c6 20 66 2b 88 48 c7 c7 c0 33 2b 88 e8 10 36 e7 ff <0f> 0b 48 8b 95 e8 fe ff ff 4c 89 f7 48 8b b5 f0 fe ff ff e8 e8 58 RSP: 0018:ffff880180ed7868 EFLAGS: 00010086 RAX: 0000000000000000 RBX: 1ffff100301daf12 RCX: ffffc9000fe31000 RDX: 000000000000798e RSI: ffffffff8165ba15 RDI: 0000000000000006 RBP: ffff880180ed7998 R08: ffff880181bbc240 R09: fffffbfff12b2254 R10: fffffbfff12b2254 R11: ffffffff895912a3 R12: ffffffff8b0e27a0 R13: ffff880180ed7970 R14: ffff880181bbc240 R15: ffff880180ed78b0 __mutex_unlock_slowpath+0x102/0x8c0 kernel/locking/mutex.c:1197 mutex_unlock+0xd/0x10 kernel/locking/mutex.c:713 loop_control_ioctl+0xf5/0x4e0 drivers/block/loop.c:2095 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f9e35e63c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000005 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9e35e646d4 R13: 00000000004c06f1 R14: 00000000004d1028 R15: 00000000ffffffff Kernel Offset: disabled Rebooting in 86400 seconds..