======================================================
WARNING: possible circular locking dependency detected
6.0.0-rc3-next-20220829 #1 Not tainted
------------------------------------------------------
syz-executor.1/5306 is trying to acquire lock:
ffff88800fe84170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x15e/0x310

but task is already holding lock:
ffff88800ff8abd0 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_change_inode_journal_flag+0x177/0x530

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&sbi->s_writepages_rwsem){++++}-{0:0}:
       percpu_down_write+0x4d/0x3d0
       ext4_ind_migrate+0x237/0x830
       ext4_fileattr_set+0x1434/0x18a0
       vfs_fileattr_set+0x77c/0xb80
       do_vfs_ioctl+0xfc2/0x1610
       __x64_sys_ioctl+0x10c/0x210
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #2 (&sb->s_type->i_mutex_key#6){++++}-{3:3}:
       down_read+0x98/0x450
       ext4_bmap+0x4e/0x470
       bmap+0xac/0x120
       jbd2_journal_bmap+0xa8/0x180
       jbd2_journal_flush+0x853/0xc00
       __ext4_ioctl+0x9e9/0x4090
       __x64_sys_ioctl+0x19a/0x210
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #1 (&journal->j_checkpoint_mutex){+.+.}-{3:3}:
       mutex_lock_io_nested+0x148/0x1310
       jbd2_journal_flush+0x19a/0xc00
       __ext4_ioctl+0x9e9/0x4090
       __x64_sys_ioctl+0x19a/0x210
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&journal->j_barrier){+.+.}-{3:3}:
       __lock_acquire+0x2a02/0x5e70
       lock_acquire+0x1a2/0x530
       __mutex_lock+0x136/0x14d0
       jbd2_journal_lock_updates+0x15e/0x310
       ext4_change_inode_journal_flag+0x17f/0x530
       ext4_fileattr_set+0x140d/0x18a0
       vfs_fileattr_set+0x77c/0xb80
       do_vfs_ioctl+0xfc2/0x1610
       __x64_sys_ioctl+0x10c/0x210
       do_syscall_64+0x3b/0x90
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

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

 Possible unsafe locking scenario:

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

 *** DEADLOCK ***

4 locks held by syz-executor.1/5306:
 #0: ffff88800ff88438 (sb_writers#3){.+.+}-{0:0}, at: do_vfs_ioctl+0xf87/0x1610
 #1: ffff88801e380400 (&sb->s_type->i_mutex_key#6){++++}-{3:3}, at: vfs_fileattr_set+0x148/0xb80
 #2: ffff88801e3805a0 (mapping.invalidate_lock){++++}-{3:3}, at: ext4_change_inode_journal_flag+0x11e/0x530
 #3: ffff88800ff8abd0 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_change_inode_journal_flag+0x177/0x530

stack backtrace:
CPU: 1 PID: 5306 Comm: syz-executor.1 Not tainted 6.0.0-rc3-next-20220829 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x8b/0xb3
 check_noncircular+0x263/0x2e0
 __lock_acquire+0x2a02/0x5e70
 lock_acquire+0x1a2/0x530
 __mutex_lock+0x136/0x14d0
 jbd2_journal_lock_updates+0x15e/0x310
 ext4_change_inode_journal_flag+0x17f/0x530
 ext4_fileattr_set+0x140d/0x18a0
 vfs_fileattr_set+0x77c/0xb80
 do_vfs_ioctl+0xfc2/0x1610
 __x64_sys_ioctl+0x10c/0x210
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fceb2c91b19
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:00007fceb0207188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fceb2da4f60 RCX: 00007fceb2c91b19
RDX: 0000000020000080 RSI: 0000000040086602 RDI: 0000000000000004
RBP: 00007fceb2cebf6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc8cec938f R14: 00007fceb0207300 R15: 0000000000022000
 </TASK>
FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 5319 Comm: syz-executor.2 Not tainted 6.0.0-rc3-next-20220829 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x8b/0xb3
 should_fail.cold+0x5/0xa
 _copy_from_user+0x2a/0x170
 kstrtouint_from_user+0xac/0x170
 proc_fail_nth_write+0x78/0x220
 vfs_write+0x2cb/0xd90
 ksys_write+0x127/0x250
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f91aaeb35ff
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 99 fd ff ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 cc fd ff ff 48
RSP: 002b:00007f91a8476170 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f91aaeb35ff
RDX: 0000000000000001 RSI: 00007f91a84761e0 RDI: 0000000000000004
RBP: 00007f91a84761d0 R08: 0000000000000000 R09: 00007f91a8475f70
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002
R13: 00007ffedd2a194f R14: 00007f91a8476300 R15: 0000000000022000
 </TASK>
random: crng reseeded on system resumption
Restarting kernel threads ... done.
random: crng reseeded on system resumption
Restarting kernel threads ... done.
random: crng reseeded on system resumption
Restarting kernel threads ... done.