loop2: detected capacity change from 0 to 512
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.2.1316/11540 is trying to acquire lock:
ffff0000fd726c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
ffff0000fd726c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1811 [inline]
ffff0000fd726c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x16c/0x2d8 fs/ext4/inode.c:3041

but task is already holding lock:
ffff0000ddf5d4d8 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
ffff0000ddf5d4d8 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6474 [inline]
ffff0000ddf5d4d8 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x33c/0x810 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+0x474/0x3ac8 fs/ext4/inode.c:2827
       ext4_writepages+0x194/0x2d8 fs/ext4/inode.c:3042
       do_writepages+0x270/0x468 mm/page-writeback.c:2571
       filemap_writeback+0x230/0x2bc mm/filemap.c:388
       filemap_flush_range mm/filemap.c:437 [inline]
       filemap_flush+0x30/0x40 mm/filemap.c:452
       ext4_alloc_da_blocks+0x104/0x414 fs/ext4/inode.c:3353
       ext4_release_file+0x68/0x2c4 fs/ext4/file.c:169
       __fput+0x340/0x744 fs/file_table.c:510
       ____fput+0x20/0x30 fs/file_table.c:538
       task_work_run+0x1c4/0x254 kernel/task_work.c:233
       resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
       __exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
       exit_to_user_mode_loop+0x10c/0x17c kernel/entry/common.c:98
       __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
       syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
       arm64_syscall_exit_to_user_mode arch/arm64/kernel/entry-common.c:88 [inline]
       el0_svc+0x18c/0x260 arch/arm64/kernel/entry-common.c:741
       el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:759
       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+0x1780/0x2f44 kernel/locking/lockdep.c:5237
       lock_acquire+0x140/0x368 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+0x16c/0x2d8 fs/ext4/inode.c:3041
       do_writepages+0x270/0x468 mm/page-writeback.c:2571
       __writeback_single_inode+0x144/0x1808 fs/fs-writeback.c:1764
       writeback_single_inode+0x3b8/0xaa0 fs/fs-writeback.c:1883
       write_inode_now+0x170/0x208 fs/fs-writeback.c:2974
       iput_final fs/inode.c:1950 [inline]
       iput+0x6bc/0xb90 fs/inode.c:2009
       ext4_xattr_block_set+0x12dc/0x2188 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+0xb18/0x13a0 fs/ext4/xattr.c:2834
       __ext4_expand_extra_isize+0x29c/0x370 fs/ext4/inode.c:6434
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
       __ext4_mark_inode_dirty+0x3a4/0x810 fs/ext4/inode.c:6555
       ext4_evict_inode+0x7a0/0xfc4 fs/ext4/inode.c:267
       evict+0x4b8/0x740 fs/inode.c:841
       iput_final fs/inode.c:1960 [inline]
       iput+0x858/0xb90 fs/inode.c:2009
       ext4_process_orphan+0x240/0x2b4 fs/ext4/orphan.c:358
       ext4_orphan_cleanup+0x7b8/0xd30 fs/ext4/orphan.c:472
       __ext4_fill_super fs/ext4/super.c:5701 [inline]
       ext4_fill_super+0x45a4/0x4d60 fs/ext4/super.c:5824
       get_tree_bdev_flags+0x380/0x434 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+0x2a4/0x540 fs/namespace.c:3834
       path_mount+0x5d0/0xa68 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+0xe8/0x23c arch/arm64/kernel/syscall.c:121
       do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:140
       el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:740
       el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:759
       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.2.1316/11540:
 #0: ffff0000c4e000d8 (&type->s_umount_key#27/1){+.+.}-{4:4}, at: alloc_super+0x220/0x8bc fs/super.c:345
 #1: ffff0000c4e00600 (sb_internal){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
 #1: ffff0000c4e00600 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline]
 #1: ffff0000c4e00600 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs/super.h:177 [inline]
 #1: ffff0000c4e00600 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x360/0xfc4 fs/ext4/inode.c:228
 #2: ffff0000ddf5d4d8 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
 #2: ffff0000ddf5d4d8 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6474 [inline]
 #2: ffff0000ddf5d4d8 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x33c/0x810 fs/ext4/inode.c:6555

stack backtrace:
CPU: 1 UID: 0 PID: 11540 Comm: syz.2.1316 Tainted: G             L      syzkaller #0 PREEMPT 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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+0x1780/0x2f44 kernel/locking/lockdep.c:5237
 lock_acquire+0x140/0x368 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+0x16c/0x2d8 fs/ext4/inode.c:3041
 do_writepages+0x270/0x468 mm/page-writeback.c:2571
 __writeback_single_inode+0x144/0x1808 fs/fs-writeback.c:1764
 writeback_single_inode+0x3b8/0xaa0 fs/fs-writeback.c:1883
 write_inode_now+0x170/0x208 fs/fs-writeback.c:2974
 iput_final fs/inode.c:1950 [inline]
 iput+0x6bc/0xb90 fs/inode.c:2009
 ext4_xattr_block_set+0x12dc/0x2188 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+0xb18/0x13a0 fs/ext4/xattr.c:2834
 __ext4_expand_extra_isize+0x29c/0x370 fs/ext4/inode.c:6434
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
 __ext4_mark_inode_dirty+0x3a4/0x810 fs/ext4/inode.c:6555
 ext4_evict_inode+0x7a0/0xfc4 fs/ext4/inode.c:267
 evict+0x4b8/0x740 fs/inode.c:841
 iput_final fs/inode.c:1960 [inline]
 iput+0x858/0xb90 fs/inode.c:2009
 ext4_process_orphan+0x240/0x2b4 fs/ext4/orphan.c:358
 ext4_orphan_cleanup+0x7b8/0xd30 fs/ext4/orphan.c:472
 __ext4_fill_super fs/ext4/super.c:5701 [inline]
 ext4_fill_super+0x45a4/0x4d60 fs/ext4/super.c:5824
 get_tree_bdev_flags+0x380/0x434 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+0x2a4/0x540 fs/namespace.c:3834
 path_mount+0x5d0/0xa68 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+0xe8/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:140
 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:740
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:759
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594
EXT4-fs error (device loop2): ext4_xattr_inode_iget:441: inode #11: comm syz.2.1316: iget: bad extra_isize 90 (inode size 256)
loop2: lost file I/O error report for ino 11 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop2): ext4_xattr_inode_iget:446: comm syz.2.1316: error while reading EA inode 11 err=-117
loop2: lost filesystem error report for type 5 error -117
EXT4-fs error (device loop2): ext4_xattr_inode_iget:441: inode #11: comm syz.2.1316: iget: bad extra_isize 90 (inode size 256)
loop2: lost file I/O error report for ino 11 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop2): ext4_xattr_inode_iget:446: comm syz.2.1316: error while reading EA inode 11 err=-117
loop2: lost filesystem error report for type 5 error -117
EXT4-fs error (device loop2): ext4_xattr_inode_iget:441: inode #18: comm syz.2.1316: iget: bad extra_isize 90 (inode size 256)
loop2: lost file I/O error report for ino 18 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop2): ext4_xattr_inode_iget:446: comm syz.2.1316: error while reading EA inode 18 err=-117
loop2: lost filesystem error report for type 5 error -117
EXT4-fs error (device loop2): ext4_xattr_inode_iget:441: inode #18: comm syz.2.1316: iget: bad extra_isize 90 (inode size 256)
loop2: lost file I/O error report for ino 18 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop2): ext4_xattr_inode_iget:446: comm syz.2.1316: error while reading EA inode 18 err=-117
loop2: lost filesystem error report for type 5 error -117
EXT4-fs (loop2): 1 orphan inode deleted
EXT4-fs (loop2): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.