1 files changed, 71 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf3.c b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf3.c
new file mode 100644
index 000000000000..99c8d1d8a187
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf3.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_legacy.h"
+#include "bpf_misc.h"
+
+struct {
+	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+	__uint(max_entries, 2);
+	__uint(key_size, sizeof(__u32));
+	__uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+__noinline
+int subprog_tail2(struct __sk_buff *skb)
+{
+	volatile char arr[64] = {};
+
+	if (load_word(skb, 0) || load_half(skb, 0))
+		bpf_tail_call_static(skb, &jmp_table, 10);
+	else
+		bpf_tail_call_static(skb, &jmp_table, 1);
+
+	__sink(arr[sizeof(arr) - 1]);
+
+	return skb->len;
+}
+
+static __noinline
+int subprog_tail(struct __sk_buff *skb)
+{
+	volatile char arr[64] = {};
+
+	bpf_tail_call_static(skb, &jmp_table, 0);
+
+	__sink(arr[sizeof(arr) - 1]);
+
+	return skb->len * 2;
+}
+
+SEC("tc")
+int classifier_0(struct __sk_buff *skb)
+{
+	volatile char arr[128] = {};
+
+	__sink(arr[sizeof(arr) - 1]);
+
+	return subprog_tail2(skb);
+}
+
+SEC("tc")
+int classifier_1(struct __sk_buff *skb)
+{
+	volatile char arr[128] = {};
+
+	__sink(arr[sizeof(arr) - 1]);
+
+	return skb->len * 3;
+}
+
+SEC("tc")
+int entry(struct __sk_buff *skb)
+{
+	volatile char arr[128] = {};
+
+	__sink(arr[sizeof(arr) - 1]);
+
+	return subprog_tail(skb);
+}
+
+char __license[] SEC("license") = "GPL";