loop8: detected capacity change from 0 to 512
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.8.776/8594 is trying to acquire lock:
ffff0000da3a4c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
ffff0000da3a4c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1811 [inline]
ffff0000da3a4c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x170/0x2dc fs/ext4/inode.c:3041

but task is already holding lock:
ffff0000dd2c8a18 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
ffff0000dd2c8a18 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6474 [inline]
ffff0000dd2c8a18 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x32c/0x828 fs/ext4/inode.c:6555

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ei->xattr_sem){++++}-{4:4}:
       down_write+0x50/0xc0 kernel/locking/rwsem.c:1625
       ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline]
       ext4_destroy_inline_data+0x30/0x114 fs/ext4/inline.c:1805
       ext4_do_writepages+0x3e4/0x3bc0 fs/ext4/inode.c:2827
       ext4_writepages+0x198/0x2dc fs/ext4/inode.c:3042
       do_writepages+0x284/0x47c mm/page-writeback.c:2571
       filemap_writeback+0x230/0x2bc mm/filemap.c:388
       filemap_fdatawrite_range mm/filemap.c:413 [inline]
       file_write_and_wait_range+0xb0/0x138 mm/filemap.c:787
       mmb_fsync_noflush+0x80/0x1bc fs/buffer.c:645
       ext4_fsync_nojournal fs/ext4/fsync.c:92 [inline]
       ext4_sync_file+0x37c/0xf20 fs/ext4/fsync.c:160
       vfs_fsync_range+0x120/0x140 fs/sync.c:186
       generic_write_sync include/linux/fs.h:2654 [inline]
       ext4_buffered_write_iter+0x24c/0x310 fs/ext4/file.c:322
       ext4_file_write_iter+0x1d8/0x1368 fs/ext4/file.c:-1
       do_iter_readv_writev+0x48c/0x6f8 fs/read_write.c:-1
       vfs_writev+0x2a8/0x630 fs/read_write.c:1059
       do_pwritev+0x11c/0x224 fs/read_write.c:1155
       __do_sys_pwritev2 fs/read_write.c:1213 [inline]
       __se_sys_pwritev2 fs/read_write.c:1204 [inline]
       __arm64_sys_pwritev2+0xdc/0x110 fs/read_write.c:1204
       __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
       invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
       el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
       do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
       el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736
       el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
       el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

-> #0 (&sbi->s_writepages_rwsem){++++}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain kernel/locking/lockdep.c:3908 [inline]
       __lock_acquire+0x17c0/0x2ebc kernel/locking/lockdep.c:5237
       lock_acquire+0x140/0x364 kernel/locking/lockdep.c:5868
       percpu_down_read_internal+0x5c/0x294 include/linux/percpu-rwsem.h:53
       percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
       ext4_writepages_down_read fs/ext4/ext4.h:1811 [inline]
       ext4_writepages+0x170/0x2dc fs/ext4/inode.c:3041
       do_writepages+0x284/0x47c mm/page-writeback.c:2571
       __writeback_single_inode+0x140/0x1880 fs/fs-writeback.c:1764
       writeback_single_inode+0x3b8/0xaa4 fs/fs-writeback.c:1883
       write_inode_now+0x170/0x208 fs/fs-writeback.c:2974
       iput_final fs/inode.c:1950 [inline]
       iput+0x6e8/0xbc0 fs/inode.c:2009
       ext4_xattr_block_set+0x1460/0x21e8 fs/ext4/xattr.c:2206
       ext4_xattr_move_to_block fs/ext4/xattr.c:2671 [inline]
       ext4_xattr_make_inode_space fs/ext4/xattr.c:2746 [inline]
       ext4_expand_extra_isize_ea+0xaf4/0x1384 fs/ext4/xattr.c:2834
       __ext4_expand_extra_isize+0x2a4/0x378 fs/ext4/inode.c:6434
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
       __ext4_mark_inode_dirty+0x394/0x828 fs/ext4/inode.c:6555
       ext4_evict_inode+0x798/0xfb8 fs/ext4/inode.c:267
       evict+0x4c0/0x74c fs/inode.c:841
       iput_final fs/inode.c:1960 [inline]
       iput+0x884/0xbc0 fs/inode.c:2009
       ext4_process_orphan+0x24c/0x2c0 fs/ext4/orphan.c:358
       ext4_orphan_cleanup+0x7d4/0xd20 fs/ext4/orphan.c:472
       __ext4_fill_super fs/ext4/super.c:5701 [inline]
       ext4_fill_super+0x4628/0x4e14 fs/ext4/super.c:5824
       get_tree_bdev_flags+0x388/0x43c fs/super.c:1694
       get_tree_bdev+0x2c/0x3c fs/super.c:1717
       ext4_get_tree+0x28/0x38 fs/ext4/super.c:5856
       vfs_get_tree+0x90/0x28c fs/super.c:1754
       fc_mount+0x24/0xac fs/namespace.c:1193
       do_new_mount_fc fs/namespace.c:3758 [inline]
       do_new_mount+0x2a4/0x538 fs/namespace.c:3834
       path_mount+0x5f0/0xa88 fs/namespace.c:4154
       do_mount+0xe8/0x148 fs/namespace.c:4167
       __do_sys_mount fs/namespace.c:4383 [inline]
       __se_sys_mount fs/namespace.c:4360 [inline]
       __arm64_sys_mount+0x334/0x380 fs/namespace.c:4360
       __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
       invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
       el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
       do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
       el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736
       el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
       el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

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.8.776/8594:
 #0: ffff0000f1bde0d8 (&type->s_umount_key#27/1){+.+.}-{4:4}, at: alloc_super+0x220/0x8f4 fs/super.c:345
 #1: ffff0000f1bde600 (sb_internal){++++}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
 #1: ffff0000f1bde600 (sb_internal){++++}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline]
 #1: ffff0000f1bde600 (sb_internal){++++}-{0:0}, at: sb_start_intwrite include/linux/fs/super.h:177 [inline]
 #1: ffff0000f1bde600 (sb_internal){++++}-{0:0}, at: ext4_evict_inode+0x360/0xfb8 fs/ext4/inode.c:228
 #2: ffff0000dd2c8a18 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
 #2: ffff0000dd2c8a18 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6474 [inline]
 #2: ffff0000dd2c8a18 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x32c/0x828 fs/ext4/inode.c:6555

stack backtrace:
CPU: 1 UID: 0 PID: 8594 Comm: syz.8.776 Tainted: G             L      syzkaller #0 PREEMPT 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/02/2026
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 dump_stack+0x1c/0x28 lib/dump_stack.c:129
 print_circular_bug+0x328/0x330 kernel/locking/lockdep.c:2043
 check_noncircular+0x158/0x174 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x17c0/0x2ebc kernel/locking/lockdep.c:5237
 lock_acquire+0x140/0x364 kernel/locking/lockdep.c:5868
 percpu_down_read_internal+0x5c/0x294 include/linux/percpu-rwsem.h:53
 percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
 ext4_writepages_down_read fs/ext4/ext4.h:1811 [inline]
 ext4_writepages+0x170/0x2dc fs/ext4/inode.c:3041
 do_writepages+0x284/0x47c mm/page-writeback.c:2571
 __writeback_single_inode+0x140/0x1880 fs/fs-writeback.c:1764
 writeback_single_inode+0x3b8/0xaa4 fs/fs-writeback.c:1883
 write_inode_now+0x170/0x208 fs/fs-writeback.c:2974
 iput_final fs/inode.c:1950 [inline]
 iput+0x6e8/0xbc0 fs/inode.c:2009
 ext4_xattr_block_set+0x1460/0x21e8 fs/ext4/xattr.c:2206
 ext4_xattr_move_to_block fs/ext4/xattr.c:2671 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2746 [inline]
 ext4_expand_extra_isize_ea+0xaf4/0x1384 fs/ext4/xattr.c:2834
 __ext4_expand_extra_isize+0x2a4/0x378 fs/ext4/inode.c:6434
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
 __ext4_mark_inode_dirty+0x394/0x828 fs/ext4/inode.c:6555
 ext4_evict_inode+0x798/0xfb8 fs/ext4/inode.c:267
 evict+0x4c0/0x74c fs/inode.c:841
 iput_final fs/inode.c:1960 [inline]
 iput+0x884/0xbc0 fs/inode.c:2009
 ext4_process_orphan+0x24c/0x2c0 fs/ext4/orphan.c:358
 ext4_orphan_cleanup+0x7d4/0xd20 fs/ext4/orphan.c:472
 __ext4_fill_super fs/ext4/super.c:5701 [inline]
 ext4_fill_super+0x4628/0x4e14 fs/ext4/super.c:5824
 get_tree_bdev_flags+0x388/0x43c fs/super.c:1694
 get_tree_bdev+0x2c/0x3c fs/super.c:1717
 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5856
 vfs_get_tree+0x90/0x28c fs/super.c:1754
 fc_mount+0x24/0xac fs/namespace.c:1193
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x2a4/0x538 fs/namespace.c:3834
 path_mount+0x5f0/0xa88 fs/namespace.c:4154
 do_mount+0xe8/0x148 fs/namespace.c:4167
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount fs/namespace.c:4360 [inline]
 __arm64_sys_mount+0x334/0x380 fs/namespace.c:4360
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594
EXT4-fs error (device loop8): ext4_xattr_inode_iget:441: inode #11: comm syz.8.776: iget: bad extra_isize 90 (inode size 256)
loop8: lost file I/O error report for ino 11 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop8): ext4_xattr_inode_iget:446: comm syz.8.776: error while reading EA inode 11 err=-117
loop8: lost filesystem error report for type 5 error -117
EXT4-fs error (device loop8): ext4_xattr_inode_iget:441: inode #11: comm syz.8.776: iget: bad extra_isize 90 (inode size 256)
loop8: lost file I/O error report for ino 11 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop8): ext4_xattr_inode_iget:446: comm syz.8.776: error while reading EA inode 11 err=-117
loop8: lost filesystem error report for type 5 error -117
EXT4-fs error (device loop8): ext4_xattr_inode_iget:441: inode #18: comm syz.8.776: iget: bad extra_isize 90 (inode size 256)
loop8: lost file I/O error report for ino 18 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop8): ext4_xattr_inode_iget:446: comm syz.8.776: error while reading EA inode 18 err=-117
loop8: lost filesystem error report for type 5 error -117
EXT4-fs error (device loop8): ext4_xattr_inode_iget:441: inode #18: comm syz.8.776: iget: bad extra_isize 90 (inode size 256)
loop8: lost file I/O error report for ino 18 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop8): ext4_xattr_inode_iget:446: comm syz.8.776: error while reading EA inode 18 err=-117
loop8: lost filesystem error report for type 5 error -117
EXT4-fs (loop8): 1 orphan inode deleted
EXT4-fs (loop8): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.