======================================================
WARNING: possible circular locking dependency detected
6.8.0-syzkaller-11409-gf6cef5f8c37f #0 Not tainted
------------------------------------------------------
kswapd0/109 is trying to acquire lock:
ffff88804aceed98 (&xfs_dir_ilock_class){++++}-{3:3}, at: xfs_ilock+0x2ef/0x3e0 fs/xfs/xfs_inode.c:206

but task is already holding lock:
ffffffff8d937a40 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x166/0x1a10 mm/vmscan.c:6782

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (fs_reclaim){+.+.}-{0:0}:
       __fs_reclaim_acquire mm/page_alloc.c:3698 [inline]
       fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3712
       might_alloc include/linux/sched/mm.h:312 [inline]
       slab_pre_alloc_hook mm/slub.c:3746 [inline]
       slab_alloc_node mm/slub.c:3827 [inline]
       kmem_cache_alloc+0x4f/0x320 mm/slub.c:3852
       radix_tree_node_alloc.constprop.0+0x7c/0x350 lib/radix-tree.c:276
       radix_tree_extend+0x1a2/0x4d0 lib/radix-tree.c:425
       __radix_tree_create lib/radix-tree.c:613 [inline]
       radix_tree_insert+0x499/0x630 lib/radix-tree.c:712
       xfs_qm_dqget_cache_insert.constprop.0+0x38/0x2c0 fs/xfs/xfs_dquot.c:826
       xfs_qm_dqget+0x182/0x4a0 fs/xfs/xfs_dquot.c:901
       xfs_qm_vop_dqalloc+0x627/0xe10 fs/xfs/xfs_qm.c:1773
       xfs_fileattr_set+0x7e8/0x2590 fs/xfs/xfs_ioctl.c:1347
       vfs_fileattr_set+0x7cc/0xc00 fs/ioctl.c:697
       ioctl_fssetxattr fs/ioctl.c:759 [inline]
       do_vfs_ioctl+0x24f/0x1a90 fs/ioctl.c:873
       __do_compat_sys_ioctl+0x149/0x330 fs/ioctl.c:998
       do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
       __do_fast_syscall_32+0x7a/0x120 arch/x86/entry/common.c:321
       do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346
       entry_SYSENTER_compat_after_hwframe+0x7a/0x84

-> #1 (&qinf->qi_tree_lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
       xfs_qm_dqget_cache_lookup+0x66/0x820 fs/xfs/xfs_dquot.c:784
       xfs_qm_dqget_inode+0x1e7/0x6d0 fs/xfs/xfs_dquot.c:986
       xfs_qm_dqattach_one+0x26f/0x530 fs/xfs/xfs_qm.c:278
       xfs_qm_dqattach_locked+0x1a8/0x2d0 fs/xfs/xfs_qm.c:345
       xfs_qm_vop_dqalloc+0x344/0xe10 fs/xfs/xfs_qm.c:1710
       xfs_create+0x422/0x1140 fs/xfs/xfs_inode.c:1041
       xfs_generic_create+0x631/0x7c0 fs/xfs/xfs_iops.c:199
       lookup_open.isra.0+0x10a1/0x13c0 fs/namei.c:3497
       open_last_lookups fs/namei.c:3566 [inline]
       path_openat+0x92f/0x2990 fs/namei.c:3796
       do_filp_open+0x1dc/0x430 fs/namei.c:3826
       do_sys_openat2+0x17a/0x1e0 fs/open.c:1406
       do_sys_open fs/open.c:1421 [inline]
       __do_sys_creat fs/open.c:1497 [inline]
       __se_sys_creat fs/open.c:1491 [inline]
       __ia32_sys_creat+0xcc/0x120 fs/open.c:1491
       do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
       __do_fast_syscall_32+0x7a/0x120 arch/x86/entry/common.c:321
       do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346
       entry_SYSENTER_compat_after_hwframe+0x7a/0x84

-> #0 (&xfs_dir_ilock_class){++++}-{3:3}:
       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+0x2478/0x3b30 kernel/locking/lockdep.c:5137
       lock_acquire kernel/locking/lockdep.c:5754 [inline]
       lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
       down_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1695
       xfs_ilock+0x2ef/0x3e0 fs/xfs/xfs_inode.c:206
       xfs_reclaim_inode fs/xfs/xfs_icache.c:945 [inline]
       xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1631 [inline]
       xfs_icwalk_ag+0xca6/0x1740 fs/xfs/xfs_icache.c:1713
       xfs_icwalk+0x57/0x100 fs/xfs/xfs_icache.c:1762
       xfs_reclaim_inodes_nr+0x182/0x250 fs/xfs/xfs_icache.c:1011
       super_cache_scan+0x409/0x550 fs/super.c:227
       do_shrink_slab+0x44f/0x1160 mm/shrinker.c:435
       shrink_slab+0x18a/0x1310 mm/shrinker.c:662
       shrink_one+0x493/0x7c0 mm/vmscan.c:4774
       shrink_many mm/vmscan.c:4835 [inline]
       lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4935
       shrink_node mm/vmscan.c:5894 [inline]
       kswapd_shrink_node mm/vmscan.c:6704 [inline]
       balance_pgdat+0x10d1/0x1a10 mm/vmscan.c:6895
       kswapd+0x5ea/0xb90 mm/vmscan.c:7164
       kthread+0x2c1/0x3a0 kernel/kthread.c:388
       ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

other info that might help us debug this:

Chain exists of:
  &xfs_dir_ilock_class --> &qinf->qi_tree_lock --> fs_reclaim

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(fs_reclaim);
                               lock(&qinf->qi_tree_lock);
                               lock(fs_reclaim);
  lock(&xfs_dir_ilock_class);

 *** DEADLOCK ***

2 locks held by kswapd0/109:
 #0: ffffffff8d937a40 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x166/0x1a10 mm/vmscan.c:6782
 #1: ffff8880727b20e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared fs/super.c:561 [inline]
 #1: ffff8880727b20e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_cache_scan+0x96/0x550 fs/super.c:196

stack backtrace:
CPU: 2 PID: 109 Comm: kswapd0 Not tainted 6.8.0-syzkaller-11409-gf6cef5f8c37f #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 check_noncircular+0x31a/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+0x2478/0x3b30 kernel/locking/lockdep.c:5137
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
 down_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1695
 xfs_ilock+0x2ef/0x3e0 fs/xfs/xfs_inode.c:206
 xfs_reclaim_inode fs/xfs/xfs_icache.c:945 [inline]
 xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1631 [inline]
 xfs_icwalk_ag+0xca6/0x1740 fs/xfs/xfs_icache.c:1713
 xfs_icwalk+0x57/0x100 fs/xfs/xfs_icache.c:1762
 xfs_reclaim_inodes_nr+0x182/0x250 fs/xfs/xfs_icache.c:1011
 super_cache_scan+0x409/0x550 fs/super.c:227
 do_shrink_slab+0x44f/0x1160 mm/shrinker.c:435
 shrink_slab+0x18a/0x1310 mm/shrinker.c:662
 shrink_one+0x493/0x7c0 mm/vmscan.c:4774
 shrink_many mm/vmscan.c:4835 [inline]
 lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4935
 shrink_node mm/vmscan.c:5894 [inline]
 kswapd_shrink_node mm/vmscan.c:6704 [inline]
 balance_pgdat+0x10d1/0x1a10 mm/vmscan.c:6895
 kswapd+0x5ea/0xb90 mm/vmscan.c:7164
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>
------------[ cut here ]------------
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 2 PID: 109 at lib/refcount.c:31 refcount_warn_saturate+0x1ed/0x210 lib/refcount.c:31
Modules linked in:
CPU: 2 PID: 109 Comm: kswapd0 Not tainted 6.8.0-syzkaller-11409-gf6cef5f8c37f #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:refcount_warn_saturate+0x1ed/0x210 lib/refcount.c:31
Code: 8b e8 a7 e4 d7 fc 90 0f 0b 90 90 e9 c3 fe ff ff e8 38 e3 14 fd c6 05 0e cf 0e 0b 01 90 48 c7 c7 00 3b 6e 8b e8 84 e4 d7 fc 90 <0f> 0b 90 90 e9 a0 fe ff ff 48 89 ef e8 72 2b 71 fd e9 44 fe ff ff
RSP: 0018:ffffc90001f9f210 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8150ca49
RDX: ffff888018d14880 RSI: ffffffff8150ca56 RDI: 0000000000000001
RBP: ffff88801dee7e3c R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 746e756f63666572 R12: ffff88801dee7e3c
R13: 0000000000000000 R14: 0000000007c401e0 R15: ffff8880164ae658
FS:  0000000000000000(0000) GS:ffff88802c400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f7f09ea0 CR3: 0000000070146000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __refcount_dec include/linux/refcount.h:336 [inline]
 refcount_dec include/linux/refcount.h:351 [inline]
 dec_stack_record_count mm/page_owner.c:215 [inline]
 __reset_page_owner+0x2ea/0x370 mm/page_owner.c:253
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_folios+0x256/0xab0 mm/page_alloc.c:2536
 shrink_folio_list+0x27c2/0x3f00 mm/vmscan.c:1495
 evict_folios+0x6e1/0x1b90 mm/vmscan.c:4537
 try_to_shrink_lruvec+0x618/0x9b0 mm/vmscan.c:4733
 shrink_one+0x3f8/0x7c0 mm/vmscan.c:4772
 shrink_many mm/vmscan.c:4835 [inline]
 lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4935
 shrink_node mm/vmscan.c:5894 [inline]
 kswapd_shrink_node mm/vmscan.c:6704 [inline]
 balance_pgdat+0x10d1/0x1a10 mm/vmscan.c:6895
 kswapd+0x5ea/0xb90 mm/vmscan.c:7164
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>