test_bpf: add bpf_skb_vlan_push/pop() tests

[linux-block.git] / kernel / bpf / core.c

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index c5bedc82bc1c540bf466c4d2e64f8663a974536d..fafa741614453c46ec9eb90d340221dcf9c3cc85 100644 (file)
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -177,6 +177,7 @@ noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
 {
        return 0;
 }
+EXPORT_SYMBOL_GPL(__bpf_call_base);
 
 /**
  *     __bpf_prog_run - run eBPF program on a given context
@@ -453,7 +454,11 @@ select_insn:
                if (unlikely(!prog))
                        goto out;
 
-               ARG1 = BPF_R1;
+               /* ARG1 at this point is guaranteed to point to CTX from
+                * the verifier side due to the fact that the tail call is
+                * handeled like a helper, that is, bpf_tail_call_proto,
+                * where arg1_type is ARG_PTR_TO_CTX.
+                */
                insn = prog->insnsi;
                goto select_insn;
 out: