XFS (loop1): Quotacheck: Done.
======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc7-syzkaller-g1950a0af2d55 #0 Not tainted
------------------------------------------------------
syz.1.727/9420 is trying to acquire lock:
ffff0000f0765790 (&lp->qli_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff0000f0765790 (&lp->qli_lock){+.+.}-{3:3}, at: xfs_dquot_detach_buf+0x38/0x178 fs/xfs/xfs_dquot.c:83

but task is already holding lock:
ffff0000d3dfb630 (&l->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff0000d3dfb630 (&l->lock){+.+.}-{3:3}, at: lock_list_lru_of_memcg+0x20c/0x450 mm/list_lru.c:77

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&l->lock){+.+.}-{3:3}:
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x48/0x60 kernel/locking/spinlock.c:154
       spin_lock include/linux/spinlock.h:351 [inline]
       lock_list_lru_of_memcg+0x20c/0x450 mm/list_lru.c:77
       list_lru_del+0x6c/0x1f4 mm/list_lru.c:202
       list_lru_del_obj+0x114/0x288 mm/list_lru.c:226
       xfs_buf_stale+0x1ac/0x300 fs/xfs/xfs_buf.c:178
       xfs_trans_binval+0x12c/0x54c fs/xfs/xfs_trans_buf.c:624
       xfs_da_shrink_inode+0x2fc/0x5bc fs/xfs/libxfs/xfs_da_btree.c:2684
       xfs_da3_join+0x404/0x8a8 fs/xfs/libxfs/xfs_da_btree.c:1193
       xfs_attr_node_remove_attr+0x1b0/0x338 fs/xfs/libxfs/xfs_attr.c:1489
       xfs_attr_set_iter+0xbcc/0x47b4 fs/xfs/libxfs/xfs_attr.c:939
       xfs_attr_finish_item+0xd4/0x198 fs/xfs/xfs_attr_item.c:505
       xfs_defer_finish_one+0x524/0xda4 fs/xfs/libxfs/xfs_defer.c:595
       xfs_defer_finish_noroll+0x99c/0x156c fs/xfs/libxfs/xfs_defer.c:707
       xfs_trans_commit+0x154/0x228 fs/xfs/xfs_trans.c:949
       xfs_attr_set+0xc80/0x1178 fs/xfs/libxfs/xfs_attr.c:1152
       xfs_attr_change+0x254/0x334 fs/xfs/xfs_xattr.c:128
       xfs_xattr_set+0x198/0x2cc fs/xfs/xfs_xattr.c:186
       __vfs_setxattr+0x3d8/0x400 fs/xattr.c:200
       __vfs_setxattr_noperm+0x110/0x578 fs/xattr.c:234
       __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:295
       vfs_setxattr+0x1a8/0x344 fs/xattr.c:321
       do_setxattr fs/xattr.c:636 [inline]
       filename_setxattr+0x260/0x404 fs/xattr.c:665
       path_setxattrat+0x370/0x41c fs/xattr.c:713
       __do_sys_setxattr fs/xattr.c:747 [inline]
       __se_sys_setxattr fs/xattr.c:743 [inline]
       __arm64_sys_setxattr+0xc0/0xdc fs/xattr.c:743
       __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
       el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
       do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
       el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
       el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
       el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

-> #1 (&bp->b_lock){+.+.}-{3:3}:
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x48/0x60 kernel/locking/spinlock.c:154
       spin_lock include/linux/spinlock.h:351 [inline]
       xfs_buf_rele_cached fs/xfs/xfs_buf.c:1084 [inline]
       xfs_buf_rele+0xe0/0x1248 fs/xfs/xfs_buf.c:1151
       xfs_trans_brelse+0xf0/0x460
       xfs_dquot_attach_buf+0x2a8/0x44c fs/xfs/xfs_dquot.c:1346
       xfs_qm_quotacheck_dqadjust+0x118/0x628 fs/xfs/xfs_qm.c:1341
       xfs_qm_dqusage_adjust+0x550/0x764 fs/xfs/xfs_qm.c:1457
       xfs_iwalk_ag_recs+0x43c/0x828 fs/xfs/xfs_iwalk.c:209
       xfs_iwalk_run_callbacks+0x1c0/0x3f4 fs/xfs/xfs_iwalk.c:370
       xfs_iwalk_ag+0x8cc/0x9c0 fs/xfs/xfs_iwalk.c:476
       xfs_iwalk_ag_work+0x10c/0x1a8 fs/xfs/xfs_iwalk.c:625
       xfs_pwork_work+0x80/0x1a4 fs/xfs/xfs_pwork.c:47
       process_one_work+0x7a8/0x15cc kernel/workqueue.c:3236
       process_scheduled_works kernel/workqueue.c:3317 [inline]
       worker_thread+0x97c/0xeec kernel/workqueue.c:3398
       kthread+0x288/0x310 kernel/kthread.c:389
       ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862

-> #0 (&lp->qli_lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain kernel/locking/lockdep.c:3904 [inline]
       __lock_acquire+0x34f0/0x7904 kernel/locking/lockdep.c:5226
       lock_acquire+0x23c/0x724 kernel/locking/lockdep.c:5849
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x48/0x60 kernel/locking/spinlock.c:154
       spin_lock include/linux/spinlock.h:351 [inline]
       xfs_dquot_detach_buf+0x38/0x178 fs/xfs/xfs_dquot.c:83
       xfs_qm_dquot_isolate+0x458/0x1620 fs/xfs/xfs_qm.c:528
       __list_lru_walk_one+0x144/0x450 mm/list_lru.c:300
       list_lru_walk_one+0x54/0x6c mm/list_lru.c:337
       list_lru_shrink_walk include/linux/list_lru.h:240 [inline]
       xfs_qm_shrink_scan+0x18c/0x378 fs/xfs/xfs_qm.c:574
       do_shrink_slab+0x62c/0x124c mm/shrinker.c:437
       shrink_slab+0xe9c/0x124c mm/shrinker.c:664
       drop_slab_node mm/vmscan.c:421 [inline]
       drop_slab+0x124/0x26c mm/vmscan.c:439
       drop_caches_sysctl_handler+0x17c/0x398 fs/drop_caches.c:68
       proc_sys_call_handler+0x64c/0x918 fs/proc/proc_sysctl.c:601
       proc_sys_write+0x2c/0x3c fs/proc/proc_sysctl.c:627
       do_iter_readv_writev+0x490/0x6d4
       vfs_writev+0x410/0xbc8 fs/read_write.c:1050
       do_writev+0x178/0x304 fs/read_write.c:1096
       __do_sys_writev fs/read_write.c:1164 [inline]
       __se_sys_writev fs/read_write.c:1161 [inline]
       __arm64_sys_writev+0x80/0x94 fs/read_write.c:1161
       __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
       el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
       do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
       el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
       el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
       el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

other info that might help us debug this:

Chain exists of:
  &lp->qli_lock --> &bp->b_lock --> &l->lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&l->lock);
                               lock(&bp->b_lock);
                               lock(&l->lock);
  lock(&lp->qli_lock);

 *** DEADLOCK ***

4 locks held by syz.1.727/9420:
 #0: ffff0000e2dc4478 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x220/0x2ac fs/file.c:1192
 #1: ffff0000cf156420 (sb_writers#4){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline]
 #1: ffff0000cf156420 (sb_writers#4){.+.+}-{0:0}, at: vfs_writev+0x3a8/0xbc8 fs/read_write.c:1048
 #2: ffff0000d3dfb630 (&l->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #2: ffff0000d3dfb630 (&l->lock){+.+.}-{3:3}, at: lock_list_lru_of_memcg+0x20c/0x450 mm/list_lru.c:77
 #3: ffff0000f0765878 (&dqp->q_qlock){+.+.}-{4:4}, at: xfs_dqlock_nowait fs/xfs/xfs_dquot.h:126 [inline]
 #3: ffff0000f0765878 (&dqp->q_qlock){+.+.}-{4:4}, at: xfs_qm_dquot_isolate+0x90/0x1620 fs/xfs/xfs_qm.c:467

stack backtrace:
CPU: 0 UID: 0 PID: 9420 Comm: syz.1.727 Not tainted 6.13.0-rc7-syzkaller-g1950a0af2d55 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C)
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120
 dump_stack+0x1c/0x28 lib/dump_stack.c:129
 print_circular_bug+0x154/0x1c0 kernel/locking/lockdep.c:2074
 check_noncircular+0x310/0x404 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain kernel/locking/lockdep.c:3904 [inline]
 __lock_acquire+0x34f0/0x7904 kernel/locking/lockdep.c:5226
 lock_acquire+0x23c/0x724 kernel/locking/lockdep.c:5849
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x48/0x60 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 xfs_dquot_detach_buf+0x38/0x178 fs/xfs/xfs_dquot.c:83
 xfs_qm_dquot_isolate+0x458/0x1620 fs/xfs/xfs_qm.c:528
 __list_lru_walk_one+0x144/0x450 mm/list_lru.c:300
 list_lru_walk_one+0x54/0x6c mm/list_lru.c:337
 list_lru_shrink_walk include/linux/list_lru.h:240 [inline]
 xfs_qm_shrink_scan+0x18c/0x378 fs/xfs/xfs_qm.c:574
 do_shrink_slab+0x62c/0x124c mm/shrinker.c:437
 shrink_slab+0xe9c/0x124c mm/shrinker.c:664
 drop_slab_node mm/vmscan.c:421 [inline]
 drop_slab+0x124/0x26c mm/vmscan.c:439
 drop_caches_sysctl_handler+0x17c/0x398 fs/drop_caches.c:68
 proc_sys_call_handler+0x64c/0x918 fs/proc/proc_sysctl.c:601
 proc_sys_write+0x2c/0x3c fs/proc/proc_sysctl.c:627
 do_iter_readv_writev+0x490/0x6d4
 vfs_writev+0x410/0xbc8 fs/read_write.c:1050
 do_writev+0x178/0x304 fs/read_write.c:1096
 __do_sys_writev fs/read_write.c:1164 [inline]
 __se_sys_writev fs/read_write.c:1161 [inline]
 __arm64_sys_writev+0x80/0x94 fs/read_write.c:1161
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
syz.1.727 (9420): drop_caches: 2