======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
kworker/u4:6/14908 is trying to acquire lock:
ffff88814dcca990 (jbd2_handle){++++}-{0:0}, at: wait_transaction_locked+0x19f/0x270 fs/jbd2/transaction.c:178

but task is already holding lock:
ffff88814dcc8c58 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2d40 fs/ext4/inode.c:2691

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&sbi->s_writepages_rwsem){.+.+}-{0:0}:
       percpu_down_read+0x46/0x1b0 include/linux/percpu-rwsem.h:51
       ext4_writepages+0x213/0x2d40 fs/ext4/inode.c:2691
       do_writepages+0x493/0x700 mm/page-writeback.c:2386
       __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657
       writeback_single_inode+0x3d2/0x8e0 fs/fs-writeback.c:1770
       write_inode_now+0x23b/0x2c0 fs/fs-writeback.c:2817
       iput_final fs/inode.c:1756 [inline]
       iput+0x599/0x880 fs/inode.c:1795
       ext4_xattr_set_entry+0x1d76/0x3f70 fs/ext4/xattr.c:1827
       ext4_xattr_block_set+0x8a7/0x2ce0 fs/ext4/xattr.c:1995
       ext4_xattr_move_to_block fs/ext4/xattr.c:2620 [inline]
       ext4_xattr_make_inode_space fs/ext4/xattr.c:2695 [inline]
       ext4_expand_extra_isize_ea+0xebe/0x18e0 fs/ext4/xattr.c:2783
       __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:5924
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:5967 [inline]
       __ext4_mark_inode_dirty+0x444/0x6c0 fs/ext4/inode.c:6045
       ext4_evict_inode+0xa55/0x1050 fs/ext4/inode.c:284
       evict+0x4b6/0x8b0 fs/inode.c:647
       ext4_orphan_cleanup+0xad8/0x1320 fs/ext4/orphan.c:472
       ext4_fill_super+0x8c65/0x93f0 fs/ext4/super.c:5006
       mount_bdev+0x28a/0x3c0 fs/super.c:1400
       legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
       vfs_get_tree+0x88/0x270 fs/super.c:1530
       do_new_mount+0x247/0xa40 fs/namespace.c:3034
       do_mount fs/namespace.c:3377 [inline]
       __do_sys_mount fs/namespace.c:3585 [inline]
       __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #1 (&ei->xattr_sem){++++}-{3:3}:
       down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
       ext4_setattr+0x736/0x1b70 fs/ext4/inode.c:5476
       notify_change+0xbc6/0xee0 fs/attr.c:505
       chown_common+0x4cc/0x680 fs/open.c:680
       do_fchownat+0x147/0x240 fs/open.c:711
       __do_sys_chown fs/open.c:731 [inline]
       __se_sys_chown fs/open.c:729 [inline]
       __x64_sys_chown+0x7e/0x90 fs/open.c:729
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (jbd2_handle){++++}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x2c66/0x7b50 kernel/locking/lockdep.c:5012
       lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
       wait_transaction_locked+0x1bb/0x270 fs/jbd2/transaction.c:178
       add_transaction_credits+0x104/0xcb0 fs/jbd2/transaction.c:242
       start_this_handle+0x723/0x1560 fs/jbd2/transaction.c:423
       jbd2__journal_start+0x2b7/0x5a0 fs/jbd2/transaction.c:521
       __ext4_journal_start_sb+0x167/0x360 fs/ext4/ext4_jbd2.c:105
       __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
       ext4_writepages+0xd7e/0x2d40 fs/ext4/inode.c:2814
       do_writepages+0x493/0x700 mm/page-writeback.c:2386
       __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657
       writeback_sb_inodes+0xaaa/0x1750 fs/fs-writeback.c:1940
       __writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2011
       wb_writeback+0x45e/0xbc0 fs/fs-writeback.c:2116
       wb_check_old_data_flush fs/fs-writeback.c:2216 [inline]
       wb_do_writeback fs/fs-writeback.c:2269 [inline]
       wb_workfn+0xb15/0xf20 fs/fs-writeback.c:2298
       process_one_work+0x867/0xff0 kernel/workqueue.c:2310
       worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
       kthread+0x42e/0x520 kernel/kthread.c:334
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

other info that might help us debug this:

Chain exists of:
  jbd2_handle --> &ei->xattr_sem --> &sbi->s_writepages_rwsem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sbi->s_writepages_rwsem);
                               lock(&ei->xattr_sem);
                               lock(&sbi->s_writepages_rwsem
);
  lock(jbd2_handle);

 *** DEADLOCK ***

4 locks held by kworker/u4:6/14908:
 #0: ffff8881445d4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc9000325fd00
 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffff88814dcc60e0 (&type->s_umount_key#32){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418
 #3: ffff88814dcc8c58 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2d40 fs/ext4/inode.c:2691

stack backtrace:
CPU: 0 PID: 14908 Comm: kworker/u4:6 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x2c66/0x7b50 kernel/locking/lockdep.c:5012
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 wait_transaction_locked+0x1bb/0x270 fs/jbd2/transaction.c:178
 add_transaction_credits+0x104/0xcb0 fs/jbd2/transaction.c:242
 start_this_handle+0x723/0x1560 fs/jbd2/transaction.c:423
 jbd2__journal_start+0x2b7/0x5a0 fs/jbd2/transaction.c:521
 __ext4_journal_start_sb+0x167/0x360 fs/ext4/ext4_jbd2.c:105
 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
 ext4_writepages+0xd7e/0x2d40 fs/ext4/inode.c:2814
 do_writepages+0x493/0x700 mm/page-writeback.c:2386
 __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657
 writeback_sb_inodes+0xaaa/0x1750 fs/fs-writeback.c:1940
 __writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2011
 wb_writeback+0x45e/0xbc0 fs/fs-writeback.c:2116
 wb_check_old_data_flush fs/fs-writeback.c:2216 [inline]
 wb_do_writeback fs/fs-writeback.c:2269 [inline]
 wb_workfn+0xb15/0xf20 fs/fs-writeback.c:2298
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>