[syzbot] [ocfs2?] possible deadlock in __ocfs2_flush_truncate_log

[syzbot <syzbot+6bf948e47f9bac7aacfa@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    4003c9e78778 Merge tag 'net-6.14-rc7' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=114d0fa8580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=eb44f62cb82f8a0a
dashboard link: https://syzkaller.appspot.com/bug?extid=6bf948e47f9bac7aacfa
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=119f2c78580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1469304c580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-4003c9e7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d5eb122d2f89/vmlinux-4003c9e7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/51856a1503a2/bzImage-4003c9e7.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/2e8806b27a27/mount_0.gz
  fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=100d7654580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6bf948e47f9bac7aacfa@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
6.14.0-rc6-syzkaller-00103-g4003c9e78778 #0 Not tainted
------------------------------------------------------
kworker/u4:1/14 is trying to acquire lock:
ffff8880447bd100 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
ffff8880447bd100 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{4:4}, at: __ocfs2_flush_truncate_log+0x388/0x1240 fs/ocfs2/alloc.c:6046

but task is already holding lock:
ffff8880447c3480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
ffff8880447c3480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: ocfs2_flush_truncate_log fs/ocfs2/alloc.c:6075 [inline]
ffff8880447c3480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: ocfs2_truncate_log_worker+0x9a/0x1b0 fs/ocfs2/alloc.c:6089

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       down_write+0x99/0x220 kernel/locking/rwsem.c:1577
       inode_lock include/linux/fs.h:877 [inline]
       ocfs2_move_extent fs/ocfs2/move_extents.c:640 [inline]
       __ocfs2_move_extents_range+0x1f0b/0x4440 fs/ocfs2/move_extents.c:860
       ocfs2_move_extents+0x3ee/0xac0 fs/ocfs2/move_extents.c:927
       ocfs2_ioctl_move_extents+0x61a/0x830 fs/ocfs2/move_extents.c:1053
       ocfs2_ioctl+0x196/0x7d0 fs/ocfs2/ioctl.c:946
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:906 [inline]
       __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
       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 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{4:4}:
       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
       down_write+0x99/0x220 kernel/locking/rwsem.c:1577
       inode_lock include/linux/fs.h:877 [inline]
       __ocfs2_flush_truncate_log+0x388/0x1240 fs/ocfs2/alloc.c:6046
       ocfs2_flush_truncate_log fs/ocfs2/alloc.c:6076 [inline]
       ocfs2_truncate_log_worker+0xa2/0x1b0 fs/ocfs2/alloc.c:6089
       process_one_work kernel/workqueue.c:3238 [inline]
       process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
       worker_thread+0x870/0xd30 kernel/workqueue.c:3400
       kthread+0x7a9/0x920 kernel/kthread.c:464
       ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5);

 *** DEADLOCK ***

3 locks held by kworker/u4:1/14:
 #0: ffff88803f7b2948 ((wq_completion)ocfs2_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88803f7b2948 ((wq_completion)ocfs2_wq){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
 #1: ffffc9000040fc60 ((work_completion)(&(&osb->osb_truncate_log_wq)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000040fc60 ((work_completion)(&(&osb->osb_truncate_log_wq)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
 #2: ffff8880447c3480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
 #2: ffff8880447c3480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: ocfs2_flush_truncate_log fs/ocfs2/alloc.c:6075 [inline]
 #2: ffff8880447c3480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: ocfs2_truncate_log_worker+0x9a/0x1b0 fs/ocfs2/alloc.c:6089

stack backtrace:
CPU: 0 UID: 0 PID: 14 Comm: kworker/u4:1 Not tainted 6.14.0-rc6-syzkaller-00103-g4003c9e78778 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: ocfs2_wq ocfs2_truncate_log_worker
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
 down_write+0x99/0x220 kernel/locking/rwsem.c:1577
 inode_lock include/linux/fs.h:877 [inline]
 __ocfs2_flush_truncate_log+0x388/0x1240 fs/ocfs2/alloc.c:6046
 ocfs2_flush_truncate_log fs/ocfs2/alloc.c:6076 [inline]
 ocfs2_truncate_log_worker+0xa2/0x1b0 fs/ocfs2/alloc.c:6089
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>


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