[v5.15] possible deadlock in ocfs2_try_to_free_truncate_log (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: aabd761612db Linux 5.15.215
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=101f82c6580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f161cbc9aef65db0
dashboard link: https://syzkaller.appspot.com/bug?extid=7564934225c15412d0e3
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f636f56d3662/disk-aabd7616.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f1a46620f40c/vmlinux-aabd7616.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9b78bb48b022/bzImage-aabd7616.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+756493...@syzkaller.appspotmail.com

============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.3.220/5084 is trying to acquire lock:
ffff888061273488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
ffff888061273488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: ocfs2_try_to_free_truncate_log+0xb1/0x370 fs/ocfs2/alloc.c:6122

but task is already holding lock:
ffff888061273488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
ffff888061273488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: ocfs2_defrag_extent fs/ocfs2/move_extents.c:253 [inline]
ffff888061273488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: __ocfs2_move_extents_range+0x1221/0x3450 fs/ocfs2/move_extents.c:865

other info that might help us debug this:
Possible unsafe locking scenario:

CPU0
----
lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);
lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);

*** DEADLOCK ***

May be due to missing lock nesting notation

5 locks held by syz.3.220/5084:
#0: ffff88814c810460 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:430
#1: ffff888061275108 (&sb->s_type->i_mutex_key#34){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#1: ffff888061275108 (&sb->s_type->i_mutex_key#34){+.+.}-{3:3}, at: ocfs2_move_extents+0x19d/0xa40 fs/ocfs2/move_extents.c:918
#2: ffff888061274da0 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_move_extents+0x3fc/0xa40 fs/ocfs2/move_extents.c:938
#3: ffff888074a16d88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#3: ffff888074a16d88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: ocfs2_reserve_suballoc_bits+0x16d/0x44b0 fs/ocfs2/suballoc.c:804
#4: ffff888061273488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#4: ffff888061273488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: ocfs2_defrag_extent fs/ocfs2/move_extents.c:253 [inline]
#4: ffff888061273488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: __ocfs2_move_extents_range+0x1221/0x3450 fs/ocfs2/move_extents.c:865

stack backtrace:
CPU: 0 PID: 5084 Comm: syz.3.220 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<TASK>
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
__lock_acquire+0x1247/0x7b50 kernel/locking/lockdep.c:-1
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
down_write+0x38/0x60 kernel/locking/rwsem.c:1551
inode_lock include/linux/fs.h:787 [inline]
ocfs2_try_to_free_truncate_log+0xb1/0x370 fs/ocfs2/alloc.c:6122
ocfs2_reserve_clusters_with_limit+0x48a/0xc10 fs/ocfs2/suballoc.c:1202
ocfs2_defrag_extent fs/ocfs2/move_extents.c:272 [inline]
__ocfs2_move_extents_range+0x15d6/0x3450 fs/ocfs2/move_extents.c:865
ocfs2_move_extents+0x409/0xa40 fs/ocfs2/move_extents.c:940
ocfs2_ioctl_move_extents+0x4d7/0x6e0 fs/ocfs2/move_extents.c:1066
ocfs2_ioctl+0x31f/0x7a0 fs/ocfs2/ioctl.c:947
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f7b16a2b0d9
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
RSP: 002b:00007f7b14c62028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7b16cb3090 RCX: 00007f7b16a2b0d9
RDX: 00002000000000c0 RSI: 0000000040406f06 RDI: 0000000000000008
RBP: 00007f7b16ac2024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7b16cb3128 R14: 00007f7b16cb3090 R15: 00007ffe5c340fe8
</TASK>


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