From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Fri, 8 Jul 2016 08:42:11 +0000 (+0200)
Subject: dnsdist: Disable eBPF support when BPF_FUNC_tail_call is not found
X-Git-Tag: rec-4.0.2~49^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7e8692aa338332c8f7d7e4d65a1a27430f9b4c61;p=thirdparty%2Fpdns.git

dnsdist: Disable eBPF support when BPF_FUNC_tail_call is not found
---

diff --git a/m4/pdns_with_ebpf.m4 b/m4/pdns_with_ebpf.m4
index 54c04854a8..af7a9cf9cf 100644
--- a/m4/pdns_with_ebpf.m4
+++ b/m4/pdns_with_ebpf.m4
@@ -18,5 +18,14 @@ AC_DEFUN([PDNS_WITH_EBPF],[
     ])
   ])
   AM_CONDITIONAL([HAVE_EBPF], [test x"$bpf_headers" = "xyes" ])
-  AS_IF([test x"$bpf_headers" = "xyes" ], [AC_DEFINE([HAVE_EBPF], [1], [Define if using eBPF.])])
+  AS_IF([test x"$bpf_headers" = "xyes" ],
+    [AC_CHECK_DECL(BPF_FUNC_tail_call,
+      [ AC_DEFINE([HAVE_EBPF], [1], [Define if using eBPF.]) ],
+      [ AS_IF([test "x$with_ebpf" = "xyes"], [
+          AC_MSG_ERROR([EBPF support requested but BPF_FUNC_tail_call not found in the eBPF headers])
+        ])
+      ],
+      [#include <linux/bpf.h>]
+    )]
+  )
 ])