EXT4-fs (loop7): 2 truncates cleaned up
EXT4-fs (loop7): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.7.3489/22192 is trying to acquire lock:
ffff88810c6fa610 (sb_internal){++++}-{0:0}, at: ext4_evict_inode+0x274/0xeb0

but task is already holding lock:
ffff88810c6feb98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x308/0x1140

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+0x32e/0x550
       __writeback_single_inode+0x133/0x11a0
       writeback_single_inode+0x4ac/0xdc0
       write_inode_now+0x1c2/0x290
       iput+0x8c1/0xe80
       ext4_xattr_block_set+0x2359/0x2ad0
       ext4_expand_extra_isize_ea+0x12cf/0x1ea0
       __ext4_expand_extra_isize+0x30d/0x400
       __ext4_mark_inode_dirty+0x45c/0x730
       ext4_evict_inode+0x7a1/0xeb0
       evict+0x61e/0xb10
       ext4_orphan_cleanup+0xc38/0x1470
       ext4_fill_super+0x59ff/0x6320
       get_tree_bdev_flags+0x431/0x4f0
       vfs_get_tree+0x92/0x2a0
       do_new_mount+0x341/0xd30
       __se_sys_mount+0x31d/0x420
       do_syscall_64+0x14d/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (sb_internal){++++}-{0:0}:
       __lock_acquire+0x15a5/0x2cf0
       lock_acquire+0xf0/0x2e0
       percpu_down_read_internal+0x48/0x1c0
       ext4_evict_inode+0x274/0xeb0
       evict+0x61e/0xb10
       ext4_ext_migrate+0xe2a/0x1140
       ext4_fileattr_set+0xf33/0x16d0
       vfs_fileattr_set+0x9f6/0xc90
       ioctl_setflags+0x189/0x1f0
       do_vfs_ioctl+0x9f1/0x1530
       __se_sys_ioctl+0x82/0x170
       do_syscall_64+0x14d/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

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

 *** DEADLOCK ***

3 locks held by syz.7.3489/22192:
 #0: ffff88810c6fa420 (sb_writers#4){++++}-{0:0}, at: mnt_want_write_file+0x60/0x200
 #1: ffff88802085da38 (&type->i_mutex_dir_key#3){++++}-{4:4}, at: vfs_fileattr_set+0x161/0xc90
 #2: ffff88810c6feb98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x308/0x1140

stack backtrace:
CPU: 1 UID: 0 PID: 22192 Comm: syz.7.3489 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
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_circular_bug+0x2e1/0x300
 check_noncircular+0x12e/0x150
 __lock_acquire+0x15a5/0x2cf0
 lock_acquire+0xf0/0x2e0
 percpu_down_read_internal+0x48/0x1c0
 ext4_evict_inode+0x274/0xeb0
 evict+0x61e/0xb10
 ext4_ext_migrate+0xe2a/0x1140
 ext4_fileattr_set+0xf33/0x16d0
 vfs_fileattr_set+0x9f6/0xc90
 ioctl_setflags+0x189/0x1f0
 do_vfs_ioctl+0x9f1/0x1530
 __se_sys_ioctl+0x82/0x170
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7ee819c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7ee908f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7ee8415fa0 RCX: 00007f7ee819c819
RDX: 0000200000000080 RSI: 0000000040086602 RDI: 0000000000000004
RBP: 00007f7ee8232c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7ee8416038 R14: 00007f7ee8415fa0 R15: 00007ffd12d24c98
 </TASK>
