diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index e2e9044..1886294 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -400,8 +400,9 @@
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	bool r;
 
-	smp_mb();
+	spin_lock(&inode->i_lock);
 	r = (ci->i_ceph_flags & mask) == mask;
+	spin_unlock(&inode->i_lock);
 	return r;
 }