From 668f0e975135d6281fdf288b7919161e0ee0347d Mon Sep 17 00:00:00 2001
From: Denis Rystsov <denis@vectorized.io>
Date: Thu, 14 Jul 2022 16:46:22 -0700
Subject: [PATCH] c/feature_table: align logical versions with v22.1.5

We use feature manager to postpone activating a feature until all nodes
in the cluster are updated to avoid a situation in which a node with a
newer version uses an updated version of a protocol to communicate with
an older version which doesn't understand it.

We tend to avoid backporting features but there are cases when we need
to do it anyway e.g. when a bug fix introduces a protocol change and we
need to use the feature manager to perform a non-interruptive upgrade.

When we do it we need to do it very carefully to preserve the feature
manager invariant:

   the series of versions and the definitions of the features must
   line up perfectly with the history of versions+features in subsequent
   releases

   https://vectorizedio.atlassian.net/wiki/spaces/CORE/pages/170491930

However if we the bugfix is added after we already introduced several
feature which we don't backport we need to update the dev branch (future
release) to be consistent with the minor "backport" release.

This change updates the dev to be consistent with v22.1.5 release which
contains a bug fix gated by rm_stm_kafka_cache feature flag.
---
 src/v/cluster/feature_table.cc |  4 ++--
 src/v/cluster/feature_table.h  | 20 ++++++++++----------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/src/v/cluster/feature_table.cc b/src/v/cluster/feature_table.cc
index 24bf521389c8..f52469a89bca 100644
--- a/src/v/cluster/feature_table.cc
+++ b/src/v/cluster/feature_table.cc
@@ -26,12 +26,12 @@ std::string_view to_string_view(feature f) {
         return "maintenance_mode";
     case feature::mtls_authentication:
         return "mtls_authentication";
+    case feature::rm_stm_kafka_cache:
+        return "rm_stm_kafka_cache";
     case feature::serde_raft_0:
         return "serde_raft_0";
     case feature::license:
         return "license";
-    case feature::rm_stm_kafka_cache:
-        return "rm_stm_kafka_cache";
     case feature::test_alpha:
         return "__test_alpha";
     }
diff --git a/src/v/cluster/feature_table.h b/src/v/cluster/feature_table.h
index 88eddf042092..557c9b08ce71 100644
--- a/src/v/cluster/feature_table.h
+++ b/src/v/cluster/feature_table.h
@@ -25,9 +25,9 @@ enum class feature : std::uint64_t {
     consumer_offsets = 0x2,
     maintenance_mode = 0x4,
     mtls_authentication = 0x8,
-    serde_raft_0 = 0x10,
-    license = 0x20,
-    rm_stm_kafka_cache = 0x40,
+    rm_stm_kafka_cache = 0x10,
+    serde_raft_0 = 0x20,
+    license = 0x40,
 
     // Dummy features for testing only
     test_alpha = uint64_t(1) << 63,
@@ -106,20 +106,20 @@ constexpr static std::array feature_schema{
     feature_spec::prepare_policy::always},
   feature_spec{
     cluster_version{4},
-    "serde_raft_0",
-    feature::serde_raft_0,
+    "rm_stm_kafka_cache",
+    feature::rm_stm_kafka_cache,
     feature_spec::available_policy::always,
     feature_spec::prepare_policy::always},
   feature_spec{
-    cluster_version{4},
-    "license",
-    feature::license,
+    cluster_version{5},
+    "serde_raft_0",
+    feature::serde_raft_0,
     feature_spec::available_policy::always,
     feature_spec::prepare_policy::always},
   feature_spec{
     cluster_version{5},
-    "rm_stm_kafka_cache",
-    feature::rm_stm_kafka_cache,
+    "license",
+    feature::license,
     feature_spec::available_policy::always,
     feature_spec::prepare_policy::always},
   feature_spec{