EXT4-fs: Warning: mounting with an experimental mount option 'dioread_nolock' for blocksize < PAGE_SIZE
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.2432/18595 is trying to acquire lock:
ffff888043942bd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1767 [inline]
ffff888043942bd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1a4/0x350 fs/ext4/inode.c:2806

but task is already holding lock:
ffff8880448d00c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:165 [inline]
ffff8880448d00c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6011 [inline]
ffff8880448d00c8 (&ei->xattr_sem){++++}-{3:3}, at: __ext4_mark_inode_dirty+0x3dc/0x6e0 fs/ext4/inode.c:6092

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ei->xattr_sem){++++}-{3:3}:
       down_write+0x97/0x200 kernel/locking/rwsem.c:1573
       ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
       ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1894
       ext4_do_writepages+0x4f0/0x3990 fs/ext4/inode.c:2604
       ext4_writepages+0x1dd/0x350 fs/ext4/inode.c:2807
       do_writepages+0x3b3/0x630 mm/page-writeback.c:2575
       filemap_fdatawrite_wbc+0x122/0x180 mm/filemap.c:390
       __filemap_fdatawrite_range mm/filemap.c:423 [inline]
       file_write_and_wait_range+0x197/0x280 mm/filemap.c:781
       generic_buffers_fsync_noflush+0x6f/0x160 fs/buffer.c:609
       ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
       ext4_sync_file+0x454/0xc00 fs/ext4/fsync.c:151
       generic_write_sync include/linux/fs.h:2651 [inline]
       ext4_buffered_write_iter+0x2c0/0x350 fs/ext4/file.c:305
       ext4_file_write_iter+0x1d9/0x1880 fs/ext4/file.c:-1
       call_write_iter include/linux/fs.h:2018 [inline]
       new_sync_write fs/read_write.c:491 [inline]
       vfs_write+0x46c/0x990 fs/read_write.c:584
       ksys_pwrite64 fs/read_write.c:699 [inline]
       __do_sys_pwrite64 fs/read_write.c:709 [inline]
       __se_sys_pwrite64 fs/read_write.c:706 [inline]
       __x64_sys_pwrite64+0x19b/0x230 fs/read_write.c:706
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&sbi->s_writepages_rwsem){++++}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
       lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
       percpu_down_read+0x44/0x1a0 include/linux/percpu-rwsem.h:51
       ext4_writepages_down_read fs/ext4/ext4.h:1767 [inline]
       ext4_writepages+0x1a4/0x350 fs/ext4/inode.c:2806
       do_writepages+0x3b3/0x630 mm/page-writeback.c:2575
       __writeback_single_inode+0x153/0xec0 fs/fs-writeback.c:1635
       writeback_single_inode+0x21f/0x760 fs/fs-writeback.c:1756
       write_inode_now+0x183/0x210 fs/fs-writeback.c:2808
       iput_final fs/inode.c:1807 [inline]
       iput+0x5ae/0x920 fs/inode.c:1846
       ext4_xattr_block_set+0x273f/0x32b0 fs/ext4/xattr.c:2199
       ext4_xattr_move_to_block fs/ext4/xattr.c:2664 [inline]
       ext4_xattr_make_inode_space fs/ext4/xattr.c:2739 [inline]
       ext4_expand_extra_isize_ea+0x12c5/0x1e80 fs/ext4/xattr.c:2827
       __ext4_expand_extra_isize+0x306/0x400 fs/ext4/inode.c:5971
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:6014 [inline]
       __ext4_mark_inode_dirty+0x45d/0x6e0 fs/ext4/inode.c:6092
       ext4_evict_inode+0x7f3/0xea0 fs/ext4/inode.c:252
       evict+0x4ca/0x8d0 fs/inode.c:705
       ext4_orphan_cleanup+0xbec/0x1420 fs/ext4/orphan.c:472
       __ext4_fill_super fs/ext4/super.c:5617 [inline]
       ext4_fill_super+0x5ed3/0x6790 fs/ext4/super.c:5740
       get_tree_bdev+0x3f3/0x520 fs/super.c:1591
       vfs_get_tree+0x8c/0x280 fs/super.c:1764
       do_new_mount+0x24b/0xa40 fs/namespace.c:3386
       do_mount fs/namespace.c:3726 [inline]
       __do_sys_mount fs/namespace.c:3935 [inline]
       __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

 Possible unsafe locking scenario:

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

 *** DEADLOCK ***

3 locks held by syz.0.2432/18595:
 #0: ffff8880439400e0 (&type->s_umount_key#31){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff8880439400e0 (&type->s_umount_key#31){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff8880439400e0 (&type->s_umount_key#31){++++}-{3:3}, at: get_tree_bdev+0x353/0x520 fs/super.c:1589
 #1: ffff888043940608 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline]
 #1: ffff888043940608 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs.h:1755 [inline]
 #1: ffff888043940608 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x2bf/0xea0 fs/ext4/inode.c:213
 #2: ffff8880448d00c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:165 [inline]
 #2: ffff8880448d00c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6011 [inline]
 #2: ffff8880448d00c8 (&ei->xattr_sem){++++}-{3:3}, at: __ext4_mark_inode_dirty+0x3dc/0x6e0 fs/ext4/inode.c:6092

stack backtrace:
CPU: 1 PID: 18595 Comm: syz.0.2432 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
 percpu_down_read+0x44/0x1a0 include/linux/percpu-rwsem.h:51
 ext4_writepages_down_read fs/ext4/ext4.h:1767 [inline]
 ext4_writepages+0x1a4/0x350 fs/ext4/inode.c:2806
 do_writepages+0x3b3/0x630 mm/page-writeback.c:2575
 __writeback_single_inode+0x153/0xec0 fs/fs-writeback.c:1635
 writeback_single_inode+0x21f/0x760 fs/fs-writeback.c:1756
 write_inode_now+0x183/0x210 fs/fs-writeback.c:2808
 iput_final fs/inode.c:1807 [inline]
 iput+0x5ae/0x920 fs/inode.c:1846
 ext4_xattr_block_set+0x273f/0x32b0 fs/ext4/xattr.c:2199
 ext4_xattr_move_to_block fs/ext4/xattr.c:2664 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2739 [inline]
 ext4_expand_extra_isize_ea+0x12c5/0x1e80 fs/ext4/xattr.c:2827
 __ext4_expand_extra_isize+0x306/0x400 fs/ext4/inode.c:5971
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6014 [inline]
 __ext4_mark_inode_dirty+0x45d/0x6e0 fs/ext4/inode.c:6092
 ext4_evict_inode+0x7f3/0xea0 fs/ext4/inode.c:252
 evict+0x4ca/0x8d0 fs/inode.c:705
 ext4_orphan_cleanup+0xbec/0x1420 fs/ext4/orphan.c:472
 __ext4_fill_super fs/ext4/super.c:5617 [inline]
 ext4_fill_super+0x5ed3/0x6790 fs/ext4/super.c:5740
 get_tree_bdev+0x3f3/0x520 fs/super.c:1591
 vfs_get_tree+0x8c/0x280 fs/super.c:1764
 do_new_mount+0x24b/0xa40 fs/namespace.c:3386
 do_mount fs/namespace.c:3726 [inline]
 __do_sys_mount fs/namespace.c:3935 [inline]
 __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb08b19d8ca
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007fb08c0cde58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb08c0cdee0 RCX: 00007fb08b19d8ca
RDX: 0000200000000180 RSI: 0000200000000080 RDI: 00007fb08c0cdea0
RBP: 0000200000000180 R08: 00007fb08c0cdee0 R09: 0000000000800700
R10: 0000000000800700 R11: 0000000000000246 R12: 0000200000000080
R13: 00007fb08c0cdea0 R14: 000000000000046f R15: 00002000000001c0
 </TASK>
EXT4-fs error (device loop0): ext4_xattr_inode_iget:441: inode #11: comm syz.0.2432: iget: bad extra_isize 90 (inode size 256)
EXT4-fs error (device loop0): ext4_xattr_inode_iget:446: comm syz.0.2432: error while reading EA inode 11 err=-117
EXT4-fs error (device loop0): ext4_xattr_inode_iget:441: inode #11: comm syz.0.2432: iget: bad extra_isize 90 (inode size 256)
EXT4-fs error (device loop0): ext4_xattr_inode_iget:446: comm syz.0.2432: error while reading EA inode 11 err=-117
EXT4-fs error (device loop0): ext4_xattr_inode_iget:441: inode #18: comm syz.0.2432: iget: bad extra_isize 90 (inode size 256)
EXT4-fs error (device loop0): ext4_xattr_inode_iget:446: comm syz.0.2432: error while reading EA inode 18 err=-117
EXT4-fs error (device loop0): ext4_xattr_inode_iget:441: inode #18: comm syz.0.2432: iget: bad extra_isize 90 (inode size 256)
EXT4-fs error (device loop0): ext4_xattr_inode_iget:446: comm syz.0.2432: error while reading EA inode 18 err=-117
EXT4-fs (loop0): 1 orphan inode deleted
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
EXT4-fs (loop0): unmounting filesystem 00000000-0000-0000-0000-000000000000.