XFS (loop5): Ending clean mount
======================================================
WARNING: possible circular locking dependency detected
6.13.0-syzkaller-09793-g69b8923f5003 #0 Not tainted
------------------------------------------------------
syz.5.141/6927 is trying to acquire lock:
ffff88805dd9b7e0 (&bp->b_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff88805dd9b7e0 (&bp->b_lock){+.+.}-{3:3}, at: xfs_buf_try_hold fs/xfs/xfs_buf.c:578 [inline]
ffff88805dd9b7e0 (&bp->b_lock){+.+.}-{3:3}, at: xfs_buf_find_insert+0x1123/0x1610 fs/xfs/xfs_buf.c:663

but task is already holding lock:
ffff88807eceb980 (&bch->bc_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff88807eceb980 (&bch->bc_lock){+.+.}-{3:3}, at: xfs_buf_find_insert+0x3da/0x1610 fs/xfs/xfs_buf.c:655

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&bch->bc_lock){+.+.}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
       spin_lock include/linux/spinlock.h:351 [inline]
       xfs_buf_rele_cached fs/xfs/xfs_buf.c:1093 [inline]
       xfs_buf_rele+0x2bf/0x1660 fs/xfs/xfs_buf.c:1147
       xfs_imap_lookup+0x26a/0x750 fs/xfs/libxfs/xfs_ialloc.c:2431
       xfs_imap+0x54d/0x1090 fs/xfs/libxfs/xfs_ialloc.c:2514
       xfs_iget_cache_miss fs/xfs/xfs_icache.c:644 [inline]
       xfs_iget+0xaf6/0x2ec0 fs/xfs/xfs_icache.c:806
       xfs_mountfs+0x14b0/0x24e0 fs/xfs/xfs_mount.c:933
       xfs_fs_fill_super+0x121d/0x1540 fs/xfs/xfs_super.c:1813
       get_tree_bdev_flags+0x48c/0x5c0 fs/super.c:1636
       vfs_get_tree+0x90/0x2b0 fs/super.c:1814
       do_new_mount+0x2be/0xb40 fs/namespace.c:3560
       do_mount fs/namespace.c:3900 [inline]
       __do_sys_mount fs/namespace.c:4111 [inline]
       __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4088
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&bp->b_lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3163 [inline]
       check_prevs_add kernel/locking/lockdep.c:3282 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
       __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
       spin_lock include/linux/spinlock.h:351 [inline]
       xfs_buf_try_hold fs/xfs/xfs_buf.c:578 [inline]
       xfs_buf_find_insert+0x1123/0x1610 fs/xfs/xfs_buf.c:663
       xfs_buf_get_map+0x149a/0x1ac0 fs/xfs/xfs_buf.c:754
       xfs_buf_read_map+0x110/0xa50 fs/xfs/xfs_buf.c:862
       xfs_trans_read_buf_map+0x260/0xab0 fs/xfs/xfs_trans_buf.c:304
       xfs_trans_read_buf fs/xfs/xfs_trans.h:212 [inline]
       xfs_imap_to_bp+0x18d/0x380 fs/xfs/libxfs/xfs_inode_buf.c:139
       xfs_iget_cache_miss fs/xfs/xfs_icache.c:664 [inline]
       xfs_iget+0xbe9/0x2ec0 fs/xfs/xfs_icache.c:806
       xfs_lookup+0x356/0x690 fs/xfs/xfs_inode.c:553
       xfs_vn_lookup+0x192/0x290 fs/xfs/xfs_iops.c:326
       __lookup_slow+0x296/0x400 fs/namei.c:1793
       lookup_slow+0x53/0x70 fs/namei.c:1810
       walk_component+0x2e1/0x410 fs/namei.c:2114
       lookup_last fs/namei.c:2612 [inline]
       path_lookupat+0x16f/0x450 fs/namei.c:2636
       filename_lookup+0x2a3/0x670 fs/namei.c:2665
       user_path_at+0x3a/0x60 fs/namei.c:3072
       __do_sys_chdir fs/open.c:557 [inline]
       __se_sys_chdir+0xbc/0x220 fs/open.c:551
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&bch->bc_lock);
                               lock(&bp->b_lock);
                               lock(&bch->bc_lock);
  lock(&bp->b_lock);

 *** DEADLOCK ***

2 locks held by syz.5.141/6927:
 #0: ffff88804e4cd870 (&inode->i_sb->s_type->i_mutex_dir_key){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:875 [inline]
 #0: ffff88804e4cd870 (&inode->i_sb->s_type->i_mutex_dir_key){++++}-{4:4}, at: lookup_slow+0x45/0x70 fs/namei.c:1809
 #1: ffff88807eceb980 (&bch->bc_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #1: ffff88807eceb980 (&bch->bc_lock){+.+.}-{3:3}, at: xfs_buf_find_insert+0x3da/0x1610 fs/xfs/xfs_buf.c:655

stack backtrace:
CPU: 0 UID: 0 PID: 6927 Comm: syz.5.141 Not tainted 6.13.0-syzkaller-09793-g69b8923f5003 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2076
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208
 check_prev_add kernel/locking/lockdep.c:3163 [inline]
 check_prevs_add kernel/locking/lockdep.c:3282 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 xfs_buf_try_hold fs/xfs/xfs_buf.c:578 [inline]
 xfs_buf_find_insert+0x1123/0x1610 fs/xfs/xfs_buf.c:663
 xfs_buf_get_map+0x149a/0x1ac0 fs/xfs/xfs_buf.c:754
 xfs_buf_read_map+0x110/0xa50 fs/xfs/xfs_buf.c:862
 xfs_trans_read_buf_map+0x260/0xab0 fs/xfs/xfs_trans_buf.c:304
 xfs_trans_read_buf fs/xfs/xfs_trans.h:212 [inline]
 xfs_imap_to_bp+0x18d/0x380 fs/xfs/libxfs/xfs_inode_buf.c:139
 xfs_iget_cache_miss fs/xfs/xfs_icache.c:664 [inline]
 xfs_iget+0xbe9/0x2ec0 fs/xfs/xfs_icache.c:806
 xfs_lookup+0x356/0x690 fs/xfs/xfs_inode.c:553
 xfs_vn_lookup+0x192/0x290 fs/xfs/xfs_iops.c:326
 __lookup_slow+0x296/0x400 fs/namei.c:1793
 lookup_slow+0x53/0x70 fs/namei.c:1810
 walk_component+0x2e1/0x410 fs/namei.c:2114
 lookup_last fs/namei.c:2612 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2636
 filename_lookup+0x2a3/0x670 fs/namei.c:2665
 user_path_at+0x3a/0x60 fs/namei.c:3072
 __do_sys_chdir fs/open.c:557 [inline]
 __se_sys_chdir+0xbc/0x220 fs/open.c:551
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fada2d8cda9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fada3c09038 EFLAGS: 00000246 ORIG_RAX: 0000000000000050
RAX: ffffffffffffffda RBX: 00007fada2fa5fa0 RCX: 00007fada2d8cda9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200001c0
RBP: 00007fada2e0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fada2fa5fa0 R15: 00007ffc9c740df8
 </TASK>