From 21ddb71bedb62ee3a5f6845c69a2d376eeb6dae9 Mon Sep 17 00:00:00 2001
From: Roland Tannous <115670425+rolandtannous@users.noreply.github.com>
Date: Wed, 3 Jun 2026 10:18:57 +0400
Subject: [PATCH] Guard model-load success path against mid-refresh
 cancellation (#5944)

* Guard model-load success path against mid-refresh cancellation

* Skip refresh state writes when cancelled during model load
---
 .../features/chat/hooks/use-chat-model-runtime.ts   | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/studio/frontend/src/features/chat/hooks/use-chat-model-runtime.ts b/studio/frontend/src/features/chat/hooks/use-chat-model-runtime.ts
index 8771bc888a..e6892b34fd 100644
--- a/studio/frontend/src/features/chat/hooks/use-chat-model-runtime.ts
+++ b/studio/frontend/src/features/chat/hooks/use-chat-model-runtime.ts
@@ -255,7 +255,8 @@ export function useChatModelRuntime() {
     [],
   );
 
-  const refresh = useCallback(async () => {
+  const refresh = useCallback(async (options?: { signal?: AbortSignal }) => {
+    const signal = options?.signal;
     setModelsError(null);
     try {
       const [listRes, statusRes, lorasRes] = await Promise.all([
@@ -264,6 +265,11 @@ export function useChatModelRuntime() {
         listLoras(),
       ]);
 
+      // Cancellation can land while the requests above are in flight (e.g. the
+      // user cancels a load during this refresh). Bail before writing any
+      // backend state back into the store -- cancelLoading already cleared it.
+      if (signal?.aborted) return;
+
       setModels(listRes.models.map(toChatModelSummary));
       setLoras(lorasRes.loras.map(toLoraSummary));
 
@@ -405,6 +411,7 @@ export function useChatModelRuntime() {
         });
       }
     } catch (error) {
+      if (signal?.aborted) return;
       const message =
         error instanceof Error ? error.message : "Failed to load models";
       setModelsError(message);
@@ -761,7 +768,7 @@ export function useChatModelRuntime() {
                 store.setParams({ ...store.params, ...p });
               }
             }
-            await refresh();
+            await refresh({ signal: abortCtrl.signal });
           } catch (error) {
             // Skip rollback if user cancelled -- model is already being unloaded.
             if (abortCtrl.signal.aborted) throw error;
@@ -1056,6 +1063,8 @@ export function useChatModelRuntime() {
 
         try {
           await performLoad();
+          // User cancelled mid-refresh; cancelLoading handles teardown.
+          if (abortCtrl.signal.aborted) return;
           if (loadToastDismissedRef.current) {
             toast.success(`${toastDisplayName} loaded`, {
               classNames: MODEL_LOADED_TOAST_CLASSNAMES,