diff --git a/net/core/filter.c b/net/core/filter.c
index 47eb1bd47aa6..a873c8fd51b6 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -79,6 +79,9 @@
 #include <net/tls.h>
 #include <net/xdp.h>
 
+/* Keep the struct bpf_fib_lookup small so that it fits into a cacheline */
+static_assert(sizeof(struct bpf_fib_lookup) == 64, "struct bpf_fib_lookup size check");
+
 static const struct bpf_func_proto *
 bpf_sk_base_func_proto(enum bpf_func_id func_id);