======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.9.912/11742 is trying to acquire lock:
ffff8881b7384060 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}, at: ocfs2_try_remove_refcount_tree+0xb6/0x320

but task is already holding lock:
ffff8881b73840f8 (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_try_remove_refcount_tree+0xa4/0x320

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&oi->ip_xattr_sem){++++}-{4:4}:
       down_read+0x47/0x2e0
       ocfs2_init_acl+0x2f7/0x7a0
       ocfs2_mknod+0x12ff/0x2030
       ocfs2_create+0x195/0x420
       path_openat+0x18bb/0x3dd0
       do_filp_open+0x1fa/0x410
       do_sys_openat2+0x121/0x200
       __x64_sys_openat+0x138/0x170
       do_syscall_64+0xfa/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&journal->j_trans_barrier){.+.+}-{4:4}:
       down_read+0x47/0x2e0
       ocfs2_start_trans+0x36a/0x6d0
       ocfs2_shutdown_local_alloc+0x200/0xa10
       ocfs2_dismount_volume+0x1e9/0x8b0
       generic_shutdown_super+0x135/0x2c0
       kill_block_super+0x44/0x90
       deactivate_locked_super+0xbc/0x130
       cleanup_mnt+0x425/0x4c0
       task_work_run+0x1d4/0x260
       exit_to_user_mode_loop+0xff/0x4f0
       do_syscall_64+0x2e3/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (sb_internal#6){.+.+}-{0:0}:
       ocfs2_start_trans+0x26b/0x6d0
       ocfs2_zero_extend+0x8b3/0x2840
       ocfs2_extend_no_holes+0x267/0x4a0
       ocfs2_expand_nonsparse_inode+0x160/0x450
       ocfs2_write_begin_nolock+0x1a6b/0x4300
       ocfs2_write_begin+0x1bb/0x310
       generic_perform_write+0x2c5/0x900
       ocfs2_file_write_iter+0x1582/0x1cf0
       do_iter_readv_writev+0x623/0x8c0
       vfs_writev+0x31a/0x960
       __se_sys_pwritev2+0x179/0x290
       do_syscall_64+0xfa/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}:
       __lock_acquire+0x15a6/0x2cf0
       lock_acquire+0x117/0x340
       down_write+0x96/0x1f0
       ocfs2_try_remove_refcount_tree+0xb6/0x320
       ocfs2_truncate_file+0xd92/0x13e0
       ocfs2_setattr+0x1510/0x1b20
       notify_change+0xc1a/0xf40
       do_truncate+0x1a4/0x220
       do_ftruncate+0x4a5/0x560
       __x64_sys_ftruncate+0x92/0xf0
       do_syscall_64+0xfa/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &ocfs2_file_ip_alloc_sem_key --> &journal->j_trans_barrier --> &oi->ip_xattr_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_xattr_sem);
                               lock(&journal->j_trans_barrier);
                               lock(&oi->ip_xattr_sem);
  lock(&ocfs2_file_ip_alloc_sem_key);

 *** DEADLOCK ***

3 locks held by syz.9.912/11742:
 #0: ffff8881b84a0420 (sb_writers#29){.+.+}-{0:0}, at: do_ftruncate+0x446/0x560
 #1: ffff8881b73843c0 (&sb->s_type->i_mutex_key#42){+.+.}-{4:4}, at: do_truncate+0x171/0x220
 #2: ffff8881b73840f8 (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_try_remove_refcount_tree+0xa4/0x320

stack backtrace:
CPU: 0 UID: 0 PID: 11742 Comm: syz.9.912 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 print_circular_bug+0x2e2/0x300
 check_noncircular+0x12e/0x150
 __lock_acquire+0x15a6/0x2cf0
 lock_acquire+0x117/0x340
 down_write+0x96/0x1f0
 ocfs2_try_remove_refcount_tree+0xb6/0x320
 ocfs2_truncate_file+0xd92/0x13e0
 ocfs2_setattr+0x1510/0x1b20
 notify_change+0xc1a/0xf40
 do_truncate+0x1a4/0x220
 do_ftruncate+0x4a5/0x560
 __x64_sys_ftruncate+0x92/0xf0
 do_syscall_64+0xfa/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd9a798f7c9
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:00007fd9a87c8038 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00007fd9a7be5fa0 RCX: 00007fd9a798f7c9
RDX: 0000000000000000 RSI: 000000000000c17a RDI: 000000000000000d
RBP: 00007fd9a79f297f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd9a7be6038 R14: 00007fd9a7be5fa0 R15: 00007ffd79016bd8
 </TASK>
