======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
kworker/u9:4/4135 is trying to acquire lock:
ffff8881182ccbc0 (&ei->xattr_sem){++++}-{4:4}, at: ext4_destroy_inline_data+0x28/0xe0

but task is already holding lock:
ffff888025600c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}:
       percpu_down_read_internal+0x48/0x1c0
       ext4_writepages+0x205/0x3b0
       do_writepages+0x338/0x560
       __writeback_single_inode+0x12e/0xf90
       writeback_single_inode+0x4ef/0xe70
       write_inode_now+0x1c2/0x290
       iput+0x98b/0xf00
       ext4_xattr_block_set+0x1b0c/0x2a80
       ext4_expand_extra_isize_ea+0x1342/0x1e70
       __ext4_expand_extra_isize+0x30d/0x400
       __ext4_mark_inode_dirty+0x455/0x700
       ext4_evict_inode+0x976/0x10c0
       evict+0x624/0xb50
       ext4_orphan_cleanup+0xc7a/0x14c0
       ext4_fill_super+0x5cb4/0x65c0
       get_tree_bdev_flags+0x430/0x4f0
       vfs_get_tree+0x92/0x2a0
       do_new_mount+0x319/0xdc0
       __se_sys_mount+0x31d/0x420
       do_syscall_64+0x174/0x580
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ei->xattr_sem){++++}-{4:4}:
       __lock_acquire+0x1520/0x2cf0
       lock_acquire+0x106/0x350
       down_write+0x96/0x200
       ext4_destroy_inline_data+0x28/0xe0
       ext4_do_writepages+0x573/0x47a0
       ext4_writepages+0x241/0x3b0
       do_writepages+0x338/0x560
       __writeback_single_inode+0x12e/0xf90
       writeback_sb_inodes+0x9de/0x1b00
       wb_writeback+0x41c/0xad0
       wb_workfn+0x431/0x10f0
       process_scheduled_works+0xa8e/0x14e0
       worker_thread+0xa47/0xfb0
       kthread+0x388/0x470
       ret_from_fork+0x514/0xb70
       ret_from_fork_asm+0x1a/0x30

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(&sbi->s_writepages_rwsem);
                               lock(&ei->xattr_sem);
                               lock(&sbi->s_writepages_rwsem);
  lock(&ei->xattr_sem);

 *** DEADLOCK ***

3 locks held by kworker/u9:4/4135:
 #0: ffff888162ad6940 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #1: ffffc90025b17c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #2: ffff888025600c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0

stack backtrace:
CPU: 0 UID: 0 PID: 4135 Comm: kworker/u9:4 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: writeback wb_workfn (flush-7:4)
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_circular_bug+0x2e1/0x300
 check_noncircular+0x12e/0x150
 __lock_acquire+0x1520/0x2cf0
 lock_acquire+0x106/0x350
 down_write+0x96/0x200
 ext4_destroy_inline_data+0x28/0xe0
 ext4_do_writepages+0x573/0x47a0
 ext4_writepages+0x241/0x3b0
 do_writepages+0x338/0x560
 __writeback_single_inode+0x12e/0xf90
 writeback_sb_inodes+0x9de/0x1b00
 wb_writeback+0x41c/0xad0
 wb_workfn+0x431/0x10f0
 process_scheduled_works+0xa8e/0x14e0
 worker_thread+0xa47/0xfb0
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
EXT4-fs error (device loop4): ext4_mb_generate_buddy:1317: group 0, block bitmap and bg descriptor inconsistent: 25 vs 150994969 free clusters
EXT4-fs (loop4): Remounting filesystem read-only
