syzbot

------------[ cut here ]------------
WARNING: CPU: 0 PID: 20194 at kernel/locking/lockdep.c:722 look_up_lock_class kernel/locking/lockdep.c:689 [inline]
WARNING: CPU: 0 PID: 20194 at kernel/locking/lockdep.c:722 register_lock_class+0x85c/0x1180 kernel/locking/lockdep.c:756
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 20194 Comm: syz-executor104 Not tainted 4.14.303-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 panic+0x1f9/0x42d kernel/panic.c:183
 __warn.cold+0x20/0x44 kernel/panic.c:547
 report_bug+0x208/0x250 lib/bug.c:183
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:967
RIP: 0010:look_up_lock_class kernel/locking/lockdep.c:722 [inline]
RIP: 0010:register_lock_class+0x85c/0x1180 kernel/locking/lockdep.c:756
RSP: 0018:ffff88809241f2c0 EFLAGS: 00010083
RAX: dffffc0000000000 RBX: ffffffff87933180 RCX: 0000000000000001
RDX: 1ffff11011cc2159 RSI: 0000000000000002 RDI: ffff88808e610ac8
RBP: ffffffff8907d290 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffff8880b28004c0 R12: ffffffff8bed0dc0
R13: ffff88808e610ab0 R14: 0000000000000000 R15: ffffffff8ba40f30
 __lock_acquire+0x167/0x3f20 kernel/locking/lockdep.c:3378
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 down_write+0x34/0x90 kernel/locking/rwsem.c:54
 inode_lock include/linux/fs.h:719 [inline]
 ext4_xattr_inode_update_ref+0xe6/0x4d0 fs/ext4/xattr.c:1027
 ext4_xattr_inode_dec_ref fs/ext4/xattr.c:1096 [inline]
 ext4_xattr_block_set+0x275/0x2a60 fs/ext4/xattr.c:2147
 ext4_xattr_set_handle+0x881/0xda0 fs/ext4/xattr.c:2411
 ext4_xattr_set+0x118/0x230 fs/ext4/xattr.c:2511
 __vfs_setxattr+0xdc/0x130 fs/xattr.c:150
 __vfs_setxattr_noperm+0xfd/0x3d0 fs/xattr.c:181
 __vfs_setxattr_locked+0x14d/0x250 fs/xattr.c:239
 vfs_setxattr+0xcf/0x230 fs/xattr.c:256
 setxattr+0x1a9/0x300 fs/xattr.c:523
 path_setxattr+0x118/0x130 fs/xattr.c:542
 SYSC_setxattr fs/xattr.c:557 [inline]
 SyS_setxattr+0x36/0x50 fs/xattr.c:553
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7f838e165289
RSP: 002b:00007f8385d302f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f838e165289
RDX: 00000000200005c0 RSI: 0000000020000180 RDI: 00000000200000c0
RBP: 00007f838e1e97b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000002000 R11: 0000000000000246 R12: 00007f838e1e97b0
R13: 0000000020000a00 R14: 0030656c69662f2e R15: 2f30656c69662f2e
Kernel Offset: disabled
Rebooting in 86400 seconds..