Add the del-reason attribute and its enum to the route attribute set,
and to the getroute reply, which the route notifications reuse.

The attribute is absent from the newroute and delroute request lists.
RTA_DEL_REASON is above strict_start_type in rtm_ipv6_policy, so
encoding it in a request is rejected with -EINVAL.

Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
---
 Documentation/netlink/specs/rt-route.yaml | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/Documentation/netlink/specs/rt-route.yaml b/Documentation/netlink/specs/rt-route.yaml
index 9f4a1a253676..e37a1301ef1d 100644
--- a/Documentation/netlink/specs/rt-route.yaml
+++ b/Documentation/netlink/specs/rt-route.yaml
@@ -78,6 +78,15 @@ definitions:
       -
         name: rta-used
         type: u32
+  -
+    name: del-reason
+    type: enum
+    name-prefix: rta-del-reason-
+    enum-name: rta-del-reason
+    entries:
+      - unspec
+      - expired
+      - ra-withdrawn
 
 attribute-sets:
   -
@@ -185,6 +194,10 @@ attribute-sets:
         type: u32
         byte-order: big-endian
         display-hint: hex
+      -
+        name: del-reason
+        type: u32
+        enum: del-reason
   -
     name: metrics
     name-prefix: rtax-
@@ -299,6 +312,7 @@ operations:
             - dport
             - nh-id
             - flowlabel
+            - del-reason
       dump:
         request:
           value: 26
@@ -313,6 +327,9 @@ operations:
       do:
         request:
           value: 24
+          # del-reason is notification-only. It is above
+          # strict_start_type in rtm_ipv6_policy, so the kernel rejects
+          # it in requests.
           attributes: &route-req-attrs
             - dst
             - src
-- 
2.43.0