loop6: detected capacity change from 0 to 512
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.6.2555/16304 is trying to acquire lock:
ffff8880378c0c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x278/0x600 mm/page-writeback.c:2571

but task is already holding lock:
ffff888076a18a18 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
ffff888076a18a18 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6474 [inline]
ffff888076a18a18 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x5f0/0x890 fs/ext4/inode.c:6555

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&ei->xattr_sem){++++}-{4:4}:
       down_write+0x8b/0x1f0 kernel/locking/rwsem.c:1625
       ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline]
       ext4_inline_data_truncate+0x1b5/0xc90 fs/ext4/inline.c:1864
       ext4_truncate+0x947/0x11a0 fs/ext4/inode.c:4619
       ext4_evict_inode+0x8a0/0x1a30 fs/ext4/inode.c:274
       evict+0x3c2/0xad0 fs/inode.c:841
       iput_final fs/inode.c:1960 [inline]
       iput.part.0+0x605/0xf50 fs/inode.c:2009
       iput+0x35/0x40 fs/inode.c:1975
       ext4_orphan_cleanup+0x71e/0x11e0 fs/ext4/orphan.c:472
       __ext4_fill_super fs/ext4/super.c:5701 [inline]
       ext4_fill_super+0x916c/0xb5d0 fs/ext4/super.c:5824
       get_tree_bdev_flags+0x38c/0x620 fs/super.c:1694
       vfs_get_tree+0x92/0x320 fs/super.c:1754
       fc_mount fs/namespace.c:1193 [inline]
       do_new_mount_fc fs/namespace.c:3758 [inline]
       do_new_mount fs/namespace.c:3834 [inline]
       path_mount+0x7d0/0x23d0 fs/namespace.c:4154
       do_mount fs/namespace.c:4167 [inline]
       __do_sys_mount fs/namespace.c:4383 [inline]
       __se_sys_mount fs/namespace.c:4360 [inline]
       __x64_sys_mount+0x293/0x310 fs/namespace.c:4360
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (sb_internal){.+.+}-{0:0}:
       percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
       percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
       __sb_start_write include/linux/fs/super.h:19 [inline]
       sb_start_intwrite include/linux/fs/super.h:177 [inline]
       ext4_evict_inode+0xf2c/0x1a30 fs/ext4/inode.c:228
       evict+0x3c2/0xad0 fs/inode.c:841
       iput_final fs/inode.c:1960 [inline]
       iput.part.0+0x605/0xf50 fs/inode.c:2009
       iput+0x35/0x40 fs/inode.c:1975
       ext4_ext_migrate+0xd5b/0x2000 fs/ext4/migrate.c:594
       __ext4_ioctl+0xd7e/0x42a0 fs/ext4/ioctl.c:1693
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:597 [inline]
       __se_sys_ioctl fs/ioctl.c:583 [inline]
       __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #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+0x14b8/0x2630 kernel/locking/lockdep.c:5237
       lock_acquire kernel/locking/lockdep.c:5868 [inline]
       lock_acquire+0x1b1/0x370 kernel/locking/lockdep.c:5825
       percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
       percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
       ext4_writepages_down_read fs/ext4/ext4.h:1811 [inline]
       ext4_writepages+0x21d/0x790 fs/ext4/inode.c:3041
       do_writepages+0x278/0x600 mm/page-writeback.c:2571
       __writeback_single_inode+0x164/0x1350 fs/fs-writeback.c:1764
       writeback_single_inode+0x4d3/0xf30 fs/fs-writeback.c:1883
       write_inode_now+0x174/0x1f0 fs/fs-writeback.c:2974
       iput_final fs/inode.c:1950 [inline]
       iput.part.0+0x7f3/0xf50 fs/inode.c:2009
       iput+0x35/0x40 fs/inode.c:1975
       ext4_xattr_block_set+0x6f7/0x3660 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+0x17c6/0x1d70 fs/ext4/xattr.c:2834
       __ext4_expand_extra_isize+0x346/0x480 fs/ext4/inode.c:6434
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
       __ext4_mark_inode_dirty+0x67d/0x890 fs/ext4/inode.c:6555
       ext4_evict_inode+0x846/0x1a30 fs/ext4/inode.c:267
       evict+0x3c2/0xad0 fs/inode.c:841
       iput_final fs/inode.c:1960 [inline]
       iput.part.0+0x605/0xf50 fs/inode.c:2009
       iput+0x35/0x40 fs/inode.c:1975
       ext4_orphan_cleanup+0x71e/0x11e0 fs/ext4/orphan.c:472
       __ext4_fill_super fs/ext4/super.c:5701 [inline]
       ext4_fill_super+0x916c/0xb5d0 fs/ext4/super.c:5824
       get_tree_bdev_flags+0x38c/0x620 fs/super.c:1694
       vfs_get_tree+0x92/0x320 fs/super.c:1754
       fc_mount fs/namespace.c:1193 [inline]
       do_new_mount_fc fs/namespace.c:3758 [inline]
       do_new_mount fs/namespace.c:3834 [inline]
       path_mount+0x7d0/0x23d0 fs/namespace.c:4154
       do_mount fs/namespace.c:4167 [inline]
       __do_sys_mount fs/namespace.c:4383 [inline]
       __se_sys_mount fs/namespace.c:4360 [inline]
       __x64_sys_mount+0x293/0x310 fs/namespace.c:4360
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &sbi->s_writepages_rwsem --> sb_internal --> &ei->xattr_sem

 Possible unsafe locking scenario:

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

 *** DEADLOCK ***

3 locks held by syz.6.2555/16304:
 #0: ffff88804e9160d8 (&type->s_umount_key#29/1){+.+.}-{4:4}, at: alloc_super+0x244/0xd20 fs/super.c:345
 #1: ffff88804e916600 (sb_internal){.+.+}-{0:0}, at: evict+0x3c2/0xad0 fs/inode.c:841
 #2: ffff888076a18a18 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
 #2: ffff888076a18a18 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6474 [inline]
 #2: ffff888076a18a18 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x5f0/0x890 fs/ext4/inode.c:6555

stack backtrace:
CPU: 0 UID: 0 PID: 16304 Comm: syz.6.2555 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043
 check_noncircular+0x146/0x160 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+0x14b8/0x2630 kernel/locking/lockdep.c:5237
 lock_acquire kernel/locking/lockdep.c:5868 [inline]
 lock_acquire+0x1b1/0x370 kernel/locking/lockdep.c:5825
 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
 ext4_writepages_down_read fs/ext4/ext4.h:1811 [inline]
 ext4_writepages+0x21d/0x790 fs/ext4/inode.c:3041
 do_writepages+0x278/0x600 mm/page-writeback.c:2571
 __writeback_single_inode+0x164/0x1350 fs/fs-writeback.c:1764
 writeback_single_inode+0x4d3/0xf30 fs/fs-writeback.c:1883
 write_inode_now+0x174/0x1f0 fs/fs-writeback.c:2974
 iput_final fs/inode.c:1950 [inline]
 iput.part.0+0x7f3/0xf50 fs/inode.c:2009
 iput+0x35/0x40 fs/inode.c:1975
 ext4_xattr_block_set+0x6f7/0x3660 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+0x17c6/0x1d70 fs/ext4/xattr.c:2834
 __ext4_expand_extra_isize+0x346/0x480 fs/ext4/inode.c:6434
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
 __ext4_mark_inode_dirty+0x67d/0x890 fs/ext4/inode.c:6555
 ext4_evict_inode+0x846/0x1a30 fs/ext4/inode.c:267
 evict+0x3c2/0xad0 fs/inode.c:841
 iput_final fs/inode.c:1960 [inline]
 iput.part.0+0x605/0xf50 fs/inode.c:2009
 iput+0x35/0x40 fs/inode.c:1975
 ext4_orphan_cleanup+0x71e/0x11e0 fs/ext4/orphan.c:472
 __ext4_fill_super fs/ext4/super.c:5701 [inline]
 ext4_fill_super+0x916c/0xb5d0 fs/ext4/super.c:5824
 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1694
 vfs_get_tree+0x92/0x320 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount fs/namespace.c:3834 [inline]
 path_mount+0x7d0/0x23d0 fs/namespace.c:4154
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount fs/namespace.c:4360 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:4360
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f469219e0ca
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:00007f469309fe58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f469309fee0 RCX: 00007f469219e0ca
RDX: 0000200000000180 RSI: 0000200000000000 RDI: 00007f469309fea0
RBP: 0000200000000180 R08: 00007f469309fee0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000000
R13: 00007f469309fea0 R14: 000000000000047a R15: 00002000000001c0
 </TASK>
EXT4-fs error (device loop6): ext4_xattr_inode_iget:441: inode #11: comm syz.6.2555: iget: bad extra_isize 90 (inode size 256)
loop6: lost file I/O error report for ino 11 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop6): ext4_xattr_inode_iget:444: comm syz.6.2555: error while reading EA inode 11 err=-117
loop6: lost filesystem error report for type 5 error -117
EXT4-fs warning (device loop6): ext4_expand_extra_isize_ea:2859: Unable to expand inode 15. Delete some EAs or run e2fsck.
EXT4-fs error (device loop6): ext4_xattr_inode_iget:441: inode #11: comm syz.6.2555: iget: bad extra_isize 90 (inode size 256)
loop6: lost file I/O error report for ino 11 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop6): ext4_xattr_inode_iget:444: comm syz.6.2555: error while reading EA inode 11 err=-117
loop6: lost filesystem error report for type 5 error -117
EXT4-fs error (device loop6): ext4_xattr_inode_iget:441: inode #18: comm syz.6.2555: iget: bad extra_isize 90 (inode size 256)
loop6: lost file I/O error report for ino 18 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop6): ext4_xattr_inode_iget:444: comm syz.6.2555: error while reading EA inode 18 err=-117
loop6: lost filesystem error report for type 5 error -117
EXT4-fs error (device loop6): ext4_xattr_inode_iget:441: inode #18: comm syz.6.2555: iget: bad extra_isize 90 (inode size 256)
loop6: lost file I/O error report for ino 18 type 5 pos 0x0 len 0x0 error -117
EXT4-fs error (device loop6): ext4_xattr_inode_iget:444: comm syz.6.2555: error while reading EA inode 18 err=-117
loop6: lost filesystem error report for type 5 error -117
EXT4-fs (loop6): 1 orphan inode deleted
EXT4-fs (loop6): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.