======================================================
WARNING: possible circular locking dependency detected
6.2.0-rc5-next-20230125 #1 Not tainted
------------------------------------------------------
syz-executor.7/16303 is trying to acquire lock:
ffff88800c160400 (&sb->s_type->i_mutex_key#6){++++}-{3:3}, at: ext4_bmap+0x52/0x470

but task is already holding lock:
ffff88801002a3f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x483/0xc90

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&journal->j_checkpoint_mutex){+.+.}-{3:3}:
       mutex_lock_io_nested+0x14c/0x1300
       jbd2_journal_flush+0x19e/0xc90
       ext4_change_inode_journal_flag+0x39d/0x550
       ext4_fileattr_set+0x14fa/0x19f0
       vfs_fileattr_set+0x7a2/0xbd0
       do_vfs_ioctl+0xfc1/0x1690
       __x64_sys_ioctl+0x110/0x210
       do_syscall_64+0x3f/0x90
       entry_SYSCALL_64_after_hwframe+0x72/0xdc

-> #2 (&journal->j_barrier){+.+.}-{3:3}:
       __mutex_lock+0x136/0x14c0
       jbd2_journal_lock_updates+0x162/0x310
       ext4_change_inode_journal_flag+0x187/0x550
       ext4_fileattr_set+0x14fa/0x19f0
       vfs_fileattr_set+0x7a2/0xbd0
       do_vfs_ioctl+0xfc1/0x1690
       __x64_sys_ioctl+0x110/0x210
       do_syscall_64+0x3f/0x90
       entry_SYSCALL_64_after_hwframe+0x72/0xdc

-> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}:
       percpu_down_write+0x51/0x350
       ext4_ind_migrate+0x23b/0x840
       ext4_fileattr_set+0x1521/0x19f0
       vfs_fileattr_set+0x7a2/0xbd0
       do_vfs_ioctl+0xfc1/0x1690
       __x64_sys_ioctl+0x110/0x210
       do_syscall_64+0x3f/0x90
       entry_SYSCALL_64_after_hwframe+0x72/0xdc

-> #0 (&sb->s_type->i_mutex_key#6){++++}-{3:3}:
       __lock_acquire+0x2dcd/0x6410
       lock_acquire.part.0+0x120/0x360
       down_read+0x9c/0x450
       ext4_bmap+0x52/0x470
       bmap+0xb0/0x130
       jbd2_journal_bmap+0xac/0x1d0
       jbd2_journal_flush+0x87f/0xc90
       __ext4_ioctl+0x9fd/0x4330
       __x64_sys_ioctl+0x19e/0x210
       do_syscall_64+0x3f/0x90
       entry_SYSCALL_64_after_hwframe+0x72/0xdc

other info that might help us debug this:

Chain exists of:
  &sb->s_type->i_mutex_key#6 --> &journal->j_barrier --> &journal->j_checkpoint_mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&journal->j_checkpoint_mutex);
                               lock(&journal->j_barrier);
                               lock(&journal->j_checkpoint_mutex);
  rlock(&sb->s_type->i_mutex_key#6);

 *** DEADLOCK ***

2 locks held by syz-executor.7/16303:
 #0: ffff88801002a170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x162/0x310
 #1: ffff88801002a3f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x483/0xc90

stack backtrace:
CPU: 1 PID: 16303 Comm: syz-executor.7 Not tainted 6.2.0-rc5-next-20230125 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x91/0xf0
 check_noncircular+0x263/0x2e0
 __lock_acquire+0x2dcd/0x6410
 lock_acquire.part.0+0x120/0x360
 down_read+0x9c/0x450
 ext4_bmap+0x52/0x470
 bmap+0xb0/0x130
 jbd2_journal_bmap+0xac/0x1d0
 jbd2_journal_flush+0x87f/0xc90
 __ext4_ioctl+0x9fd/0x4330
 __x64_sys_ioctl+0x19e/0x210
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f959bea0b19
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f95993d4188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f959bfb40e0 RCX: 00007f959bea0b19
RDX: 0000000020000000 RSI: 000000004004662b RDI: 0000000000000008
RBP: 00007f959befaf6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc2bc78a8f R14: 00007f95993d4300 R15: 0000000000022000
 </TASK>