1 files changed, 14 insertions, 21 deletions

diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 17e0d7265dfd..bd0ee312dac9 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -896,38 +896,31 @@ int svc_register(const struct svc_serv *serv, const int family,
         return error;
 }
 
-#ifdef CONFIG_SUNRPC_REGISTER_V4
-
+/*
+ * If user space is running rpcbind, it should take the v4 UNSET
+ * and clear everything for this [program, version].  If user space
+ * is running portmap, it will reject the v4 UNSET, but won't have
+ * any "inet6" entries anyway.  So a PMAP_UNSET should be sufficient
+ * in this case to clear all existing entries for [program, version].
+ */
 static void __svc_unregister(const u32 program, const u32 version,
                              const char *progname)
 {
-        struct sockaddr_in6 sin6 = {
-                .sin6_family            = AF_INET6,
-                .sin6_addr              = IN6ADDR_ANY_INIT,
-                .sin6_port              = 0,
-        };
         int error;
 
-        error = rpcb_v4_register(program, version,
-                                (struct sockaddr *)&sin6, "");
-        dprintk("svc: %s(%sv%u), error %d\n",
-                        __func__, progname, version, error);
-}
-
-#else   /* CONFIG_SUNRPC_REGISTER_V4 */
+        error = rpcb_v4_register(program, version, NULL, "");
 
-static void __svc_unregister(const u32 program, const u32 version,
-                             const char *progname)
-{
-        int error;
+        /*
+         * User space didn't support rpcbind v4, so retry this
+         * request with the legacy rpcbind v2 protocol.
+         */
+        if (error == -EPROTONOSUPPORT)
+                error = rpcb_register(program, version, 0, 0);
 
-        error = rpcb_register(program, version, 0, 0);
         dprintk("svc: %s(%sv%u), error %d\n",
                         __func__, progname, version, error);
 }
 
-#endif  /* CONFIG_SUNRPC_REGISTER_V4 */
-
 /*
  * All netids, bind addresses and ports registered for [program, version]
  * are removed from the local rpcbind database (if the service is not