diff --git a/fs/mbcache.c b/fs/mbcache.c
index d818fd2..b8b8b9c 100644
--- a/fs/mbcache.c
+++ b/fs/mbcache.c
@@ -269,6 +269,9 @@ static unsigned long mb_cache_count(struct shrinker *shrink,
 	struct mb_cache *cache = container_of(shrink, struct mb_cache,
 					      c_shrink);
 
+	/* Unlikely, but not impossible */
+	if (unlikely(cache->c_entry_count < 0))
+		return 0;
 	return cache->c_entry_count;
 }