diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 206587820fec..3a74759b59ee 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -346,6 +346,42 @@ int btrfs_verify_qgroup_counts(const struct btrfs_fs_info *fs_info, u64 qgroupid
 }
 #endif
 
+static bool squota_check_parent_usage(struct btrfs_fs_info *fs_info, struct btrfs_qgroup *parent)
+{
+	u64 excl_sum = 0;
+	u64 rfer_sum = 0;
+	u64 excl_cmpr_sum = 0;
+	u64 rfer_cmpr_sum = 0;
+	struct btrfs_qgroup_list *glist;
+	int nr_members = 0;
+	bool mismatch;
+
+	if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
+		return false;
+	if (btrfs_qgroup_level(parent->qgroupid) == 0)
+		return false;
+
+	/* Eligible parent qgroup. Squota; level > 0; empty members list. */
+	list_for_each_entry(glist, &parent->members, next_member) {
+		excl_sum += glist->member->excl;
+		rfer_sum += glist->member->rfer;
+		excl_cmpr_sum += glist->member->excl_cmpr;
+		rfer_cmpr_sum += glist->member->rfer_cmpr;
+		nr_members++;
+	}
+	mismatch = (parent->excl != excl_sum || parent->rfer != rfer_sum ||
+		    parent->excl_cmpr != excl_cmpr_sum || parent->rfer_cmpr != excl_cmpr_sum);
+
+	WARN(mismatch,
+	     "parent squota qgroup %hu/%llu has mismatched usage from its %d members. "
+	     "%llu %llu %llu %llu vs %llu %llu %llu %llu\n",
+	     btrfs_qgroup_level(parent->qgroupid),
+	     btrfs_qgroup_subvolid(parent->qgroupid), nr_members, parent->excl,
+	     parent->rfer, parent->excl_cmpr, parent->rfer_cmpr, excl_sum,
+	     rfer_sum, excl_cmpr_sum, rfer_cmpr_sum);
+	return mismatch;
+}
+
 __printf(2, 3)
 static void qgroup_mark_inconsistent(struct btrfs_fs_info *fs_info, const char *fmt, ...)
 {
@@ -1562,6 +1598,7 @@ int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst
 		goto out;
 	}
 	ret = quick_update_accounting(fs_info, src, dst, 1);
+	squota_check_parent_usage(fs_info, parent);
 	spin_unlock(&fs_info->qgroup_lock);
 out:
 	kfree(prealloc);
@@ -1618,6 +1655,8 @@ static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
 		spin_lock(&fs_info->qgroup_lock);
 		del_relation_rb(fs_info, src, dst);
 		ret = quick_update_accounting(fs_info, src, dst, -1);
+		ASSERT(parent);
+		squota_check_parent_usage(fs_info, parent);
 		spin_unlock(&fs_info->qgroup_lock);
 	}
 out: