diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
index cad813c..9053f4f 100644
--- a/Source/WebCore/ChangeLog
+++ b/Source/WebCore/ChangeLog
@@ -1,3 +1,28 @@
+2019-11-08  Youenn Fablet  <youenn@apple.com>
+
+        SWServerWorker in redundant state do not need to process messages from the context process
+        https://bugs.webkit.org/show_bug.cgi?id=204019
+
+        Reviewed by Chris Dumez.
+
+        When a service worker is marked as redundant in network process, it might still receive some messages like didFinishActivation or didFinishInstall.
+        In that state, we do not need to process these messages.
+        Did some refactoring to directly pass the service worker to the job queue.
+        This makes it clear the registration and service worker are the correct ones.
+
+        * workers/service/server/SWServer.cpp:
+        (WebCore::SWServer::didFinishInstall):
+        Pass the worker instead of its identifier.
+        * workers/service/server/SWServerJobQueue.cpp:
+        (WebCore::SWServerJobQueue::didFinishInstall):
+        Now that we are given the service worker, get its registration directly.
+        * workers/service/server/SWServerJobQueue.h:
+        * workers/service/server/SWServerWorker.cpp:
+        (WebCore::SWServerWorker::didFinishInstall):
+        Exit early in redundant state.
+        (WebCore::SWServerWorker::didFinishActivation):
+        Exit early in redundant state.
+
 2019-11-08  youenn fablet  <youenn@apple.com>
 
         XMLHttpRequestUpload should be exposed in dedicated workers
diff --git a/Source/WebCore/workers/service/server/SWServer.cpp b/Source/WebCore/workers/service/server/SWServer.cpp
index dbe9a30..c764baa 100644
--- a/Source/WebCore/workers/service/server/SWServer.cpp
+++ b/Source/WebCore/workers/service/server/SWServer.cpp
@@ -445,7 +445,7 @@
         RELEASE_LOG_ERROR(ServiceWorker, "%p - SWServer::didFinishInstall: Failed SW install for job %s", this, jobDataIdentifier->loggingString().utf8().data());
 
     if (auto* jobQueue = m_jobQueues.get(worker.registrationKey()))
-        jobQueue->didFinishInstall(*jobDataIdentifier, worker.identifier(), wasSuccessful);
+        jobQueue->didFinishInstall(*jobDataIdentifier, worker, wasSuccessful);
 }
 
 void SWServer::didFinishActivation(SWServerWorker& worker)
diff --git a/Source/WebCore/workers/service/server/SWServerJobQueue.cpp b/Source/WebCore/workers/service/server/SWServerJobQueue.cpp
index 6d7cda0..487cc75 100644
--- a/Source/WebCore/workers/service/server/SWServerJobQueue.cpp
+++ b/Source/WebCore/workers/service/server/SWServerJobQueue.cpp
@@ -177,25 +177,21 @@
 }
 
 // https://w3c.github.io/ServiceWorker/#install
-void SWServerJobQueue::didFinishInstall(const ServiceWorkerJobDataIdentifier& jobDataIdentifier, ServiceWorkerIdentifier identifier, bool wasSuccessful)
+void SWServerJobQueue::didFinishInstall(const ServiceWorkerJobDataIdentifier& jobDataIdentifier, SWServerWorker& worker, bool wasSuccessful)
 {
     if (!isCurrentlyProcessingJob(jobDataIdentifier))
         return;
 
-    auto* registration = m_server.getRegistration(m_registrationKey);
+    auto* registration = worker.registration();
     ASSERT(registration);
-    ASSERT(registration->installingWorker());
-    ASSERT(registration->installingWorker()->identifier() == identifier);
+    ASSERT(registration->installingWorker() == &worker);
 
     if (!wasSuccessful) {
-        RefPtr<SWServerWorker> worker = m_server.workerByID(identifier);
-        RELEASE_ASSERT(worker);
-
-        worker->terminate();
+        worker.terminate();
         // Run the Update Registration State algorithm passing registration, "installing" and null as the arguments.
         registration->updateRegistrationState(ServiceWorkerRegistrationState::Installing, nullptr);
         // Run the Update Worker State algorithm passing registration's installing worker and redundant as the arguments.
-        registration->updateWorkerState(*worker, ServiceWorkerState::Redundant);
+        registration->updateWorkerState(worker, ServiceWorkerState::Redundant);
 
         // If newestWorker is null, invoke Clear Registration algorithm passing registration as its argument.
         if (!registration->getNewestWorker())
@@ -211,12 +207,9 @@
         registration->updateWorkerState(*waitingWorker, ServiceWorkerState::Redundant);
     }
 
-    auto* installing = registration->installingWorker();
-    ASSERT(installing);
-
-    registration->updateRegistrationState(ServiceWorkerRegistrationState::Waiting, installing);
+    registration->updateRegistrationState(ServiceWorkerRegistrationState::Waiting, &worker);
     registration->updateRegistrationState(ServiceWorkerRegistrationState::Installing, nullptr);
-    registration->updateWorkerState(*installing, ServiceWorkerState::Installed);
+    registration->updateWorkerState(worker, ServiceWorkerState::Installed);
 
     finishCurrentJob();
 
diff --git a/Source/WebCore/workers/service/server/SWServerJobQueue.h b/Source/WebCore/workers/service/server/SWServerJobQueue.h
index 75a0cbd..0a9777e 100644
--- a/Source/WebCore/workers/service/server/SWServerJobQueue.h
+++ b/Source/WebCore/workers/service/server/SWServerJobQueue.h
@@ -34,6 +34,8 @@
 
 namespace WebCore {
 
+class SWServerWorker;
+
 class SWServerJobQueue {
     WTF_MAKE_FAST_ALLOCATED;
 public:
@@ -51,7 +53,7 @@
     void scriptFetchFinished(SWServer::Connection&, const ServiceWorkerFetchResult&);
     void scriptContextFailedToStart(const ServiceWorkerJobDataIdentifier&, ServiceWorkerIdentifier, const String& message);
     void scriptContextStarted(const ServiceWorkerJobDataIdentifier&, ServiceWorkerIdentifier);
-    void didFinishInstall(const ServiceWorkerJobDataIdentifier&, ServiceWorkerIdentifier, bool wasSuccessful);
+    void didFinishInstall(const ServiceWorkerJobDataIdentifier&, SWServerWorker&, bool wasSuccessful);
     void didResolveRegistrationPromise();
     void cancelJobsFromConnection(SWServerConnectionIdentifier);
     void cancelJobsFromServiceWorker(ServiceWorkerIdentifier);
diff --git a/Source/WebCore/workers/service/server/SWServerWorker.cpp b/Source/WebCore/workers/service/server/SWServerWorker.cpp
index 37e5700..655d70d 100644
--- a/Source/WebCore/workers/service/server/SWServerWorker.cpp
+++ b/Source/WebCore/workers/service/server/SWServerWorker.cpp
@@ -118,14 +118,24 @@
 
 void SWServerWorker::didFinishInstall(const Optional<ServiceWorkerJobDataIdentifier>& jobDataIdentifier, bool wasSuccessful)
 {
+    auto state = this->state();
+    if (state == ServiceWorkerState::Redundant)
+        return;
+
     ASSERT(m_server);
+    RELEASE_ASSERT(state == ServiceWorkerState::Installing);
     if (m_server)
         m_server->didFinishInstall(jobDataIdentifier, *this, wasSuccessful);
 }
 
 void SWServerWorker::didFinishActivation()
 {
+    auto state = this->state();
+    if (state == ServiceWorkerState::Redundant)
+        return;
+
     ASSERT(m_server);
+    RELEASE_ASSERT(state == ServiceWorkerState::Activating);
     if (m_server)
         m_server->didFinishActivation(*this);
 }