(kafka) branch 4.1 updated: MINOR: Ensure proper visibility of attribute accesses across threads (#21020)

[chia7712]

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chia7712 pushed a commit to branch 4.1
in repository https://gitbox.apache.org/repos/asf/kafka.git


The following commit(s) were added to refs/heads/4.1 by this push:
     new 36aeed49a4d MINOR: Ensure proper visibility of attribute accesses 
across threads (#21020)
36aeed49a4d is described below

commit 36aeed49a4def9ce8784cfa6410991170a78ed81
Author: majialong <majialo...@gmail.com>
AuthorDate: Sat Nov 29 20:34:00 2025 +0800

    MINOR: Ensure proper visibility of attribute accesses across threads 
(#21020)
    
    backport https://github.com/apache/kafka/pull/21014
    
    Reviewers: Chia-Ping Tsai <chia7...@gmail.com>
---
 .../org/apache/kafka/coordinator/common/runtime/CoordinatorRuntime.java | 2 +-
 .../org/apache/kafka/coordinator/group/GroupCoordinatorService.java     | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git 
a/coordinator-common/src/main/java/org/apache/kafka/coordinator/common/runtime/CoordinatorRuntime.java
 
b/coordinator-common/src/main/java/org/apache/kafka/coordinator/common/runtime/CoordinatorRuntime.java
index 901acd3d7fd..fb94cb05942 100644
--- 
a/coordinator-common/src/main/java/org/apache/kafka/coordinator/common/runtime/CoordinatorRuntime.java
+++ 
b/coordinator-common/src/main/java/org/apache/kafka/coordinator/common/runtime/CoordinatorRuntime.java
@@ -571,7 +571,7 @@ public class CoordinatorRuntime<S extends 
CoordinatorShard<U>, U> implements Aut
         /**
          * The current state.
          */
-        CoordinatorState state;
+        volatile CoordinatorState state;
 
         /**
          * The current epoch of the coordinator. This represents
diff --git 
a/group-coordinator/src/main/java/org/apache/kafka/coordinator/group/GroupCoordinatorService.java
 
b/group-coordinator/src/main/java/org/apache/kafka/coordinator/group/GroupCoordinatorService.java
index 4e0e03265a6..79e5b8e2859 100644
--- 
a/group-coordinator/src/main/java/org/apache/kafka/coordinator/group/GroupCoordinatorService.java
+++ 
b/group-coordinator/src/main/java/org/apache/kafka/coordinator/group/GroupCoordinatorService.java
@@ -331,7 +331,7 @@ public class GroupCoordinatorService implements 
GroupCoordinator {
      * The metadata image to extract topic id to names map.
      * This is initialised when the {@link 
GroupCoordinator#onNewMetadataImage(MetadataImage, MetadataDelta)} is called
      */
-    private MetadataImage metadataImage = null;
+    private volatile MetadataImage metadataImage = null;
 
     /**
      *