From 0bf161f1bcd12804bb375607097e0edf0560fd81 Mon Sep 17 00:00:00 2001
From: Cursor Agent <cursoragent@cursor.com>
Date: Wed, 11 Nov 2026 10:35:05 +0000
Subject: [PATCH] fix(kuna): resolve the function deadline before taking a run
 slot

An invalid REA_KUNA_TIMEOUT_MS throws once its runtime override is reset. That check now happens before either shared-slot acquisition, so a failed independent decompile cannot leave the provider-wide pool blocked.
---
 src/config/kunaFunctionRunAdmission.test.ts | 61 +++++++++++++++++++++
 src/kuna/KunaSessionClient.ts               | 48 ++++++++++++++--
 2 files changed, 105 insertions(+), 4 deletions(-)
 create mode 100644 src/config/kunaFunctionRunAdmission.test.ts

diff --git a/src/config/kunaFunctionRunAdmission.test.ts b/src/config/kunaFunctionRunAdmission.test.ts
new file mode 100644
index 0000000000..4686ae3495
--- /dev/null
+++ b/src/config/kunaFunctionRunAdmission.test.ts
@@ -0,0 +1,61 @@
+import { setImmediate } from "node:timers/promises";
+
+import { expect, it } from "vitest";
+
+import { runWithAnalysisOperationSnapshot } from "../domain/analysisOperationSnapshot.js";
+import type { KunaConfiguration } from "../kuna/KunaConfiguration.js";
+import { KunaRunSlots } from "../kuna/KunaRunSlots.js";
+import { reserveKunaFunctionRun } from "../kuna/KunaSessionClient.js";
+
+const configuration = {
+  command: "/usr/bin/kuna",
+  cacheRoot: "/tmp/kuna-cache",
+  cacheMaxBytes: 4 * 1024 ** 3,
+  projectTimeoutMs: 30 * 60 * 1000,
+  projectTimeoutSource: "default",
+  projectTimeoutLaunchValid: true,
+  functionTimeoutMs: 120_000,
+  functionTimeoutSource: "default",
+  functionTimeoutLaunchValid: false,
+  jobs: 1,
+} satisfies KunaConfiguration;
+
+it("does not take a run slot when the function deadline is no longer valid", async () => {
+  const slots = new KunaRunSlots(1);
+  const signal = new AbortController().signal;
+  await expect(
+    reserveKunaFunctionRun(slots, signal, configuration),
+  ).rejects.toThrow(
+    /REA_KUNA_TIMEOUT_MS is not a valid launch seed and no runtime override is active/,
+  );
+  const released = await slots.acquire(AbortSignal.timeout(50));
+  expect(released).toEqual(expect.any(Function));
+  released?.();
+});
+
+it("releases the function-run slot after the accepted deadline is finished", async () => {
+  const slots = new KunaRunSlots(1);
+  const signal = new AbortController().signal;
+  const reserved = await runWithAnalysisOperationSnapshot(
+    {
+      revision: 1,
+      overrides: { "kuna.function_timeout_ms": 5000 },
+    },
+    () => reserveKunaFunctionRun(slots, signal, configuration),
+  );
+  expect(reserved?.deadline).toEqual({
+    setting: "REA_KUNA_TIMEOUT_MS",
+    ms: 5000,
+    source: "runtime",
+  });
+  const next = slots.acquire(AbortSignal.timeout(50));
+  let granted = false;
+  void next.then((release) => {
+    granted = release !== undefined;
+  });
+  await setImmediate();
+  expect(granted).toBe(false);
+  reserved?.release();
+  expect(await next).toEqual(expect.any(Function));
+  (await next)?.();
+});
diff --git a/src/kuna/KunaSessionClient.ts b/src/kuna/KunaSessionClient.ts
index 4030313cfb..2a84adb912 100644
--- a/src/kuna/KunaSessionClient.ts
+++ b/src/kuna/KunaSessionClient.ts
@@ -362,6 +362,24 @@ const procedureSelectorSchema = z.string().min(1);
  * the background; assembly waits for it. Kuna always runs on a private copy
  * whose digest matches the selected target.
  */
+/**
+ * Resolve the function deadline before taking a shared run slot. A throw from
+ * an invalid launch seed must not leave the slot acquired.
+ */
+export const reserveKunaFunctionRun = async (
+  slots: KunaRunSlots,
+  signal: AbortSignal,
+  configuration: KunaConfiguration,
+): Promise<
+  | { readonly deadline: KunaDeadline; readonly release: KunaRunRelease }
+  | undefined
+> => {
+  const deadline = kunaFunctionDeadline(configuration);
+  const release = await slots.acquire(signal);
+  if (release === undefined) return undefined;
+  return { deadline, release };
+};
+
 export class KunaSessionClient implements AnalysisClient {
   readonly #target: BinaryTarget;
   readonly #profile: AnalysisProfileCommitment | undefined;
@@ -1604,9 +1622,31 @@ export class KunaSessionClient implements AnalysisClient {
   ): Promise<SingleFunctionOutcome> {
     const prepared = await this.#commands.prepare();
     if (!prepared.ok) return prepared;
-    const admitted = independent
-      ? await this.#runSlots.acquire(signal)
-      : await this.#admitSingleFunction(signal);
+    if (independent) {
+      const reserved = await reserveKunaFunctionRun(
+        this.#runSlots,
+        signal,
+        installation.configuration,
+      );
+      if (reserved === undefined)
+        return err(
+          new AnalysisCancelledError(operation, { cause: signal.reason }),
+        );
+      const run = await this.#commands.run({
+        installation,
+        arguments: (input) => ["decompile", input, address, "--addr"],
+        operation,
+        deadline: reserved.deadline,
+        outputBytes: KUNA_FUNCTION_TEXT_BYTES,
+        signal,
+        releaseRun: reserved.release,
+      });
+      return run.ok ? ok(run.value.stdout.text.replace(/\n+$/u, "")) : run;
+    }
+    // The shared slot is taken only after the deadline is known. A throw from
+    // a reset override must not leave that slot acquired.
+    const deadline = kunaFunctionDeadline(installation.configuration);
+    const admitted = await this.#admitSingleFunction(signal);
     if (admitted === EXPORT_READY) return admitted;
     if (admitted === undefined)
       return err(
@@ -1616,7 +1656,7 @@ export class KunaSessionClient implements AnalysisClient {
       installation,
       arguments: (input) => ["decompile", input, address, "--addr"],
       operation,
-      deadline: kunaFunctionDeadline(installation.configuration),
+      deadline,
       outputBytes: KUNA_FUNCTION_TEXT_BYTES,
       signal,
       releaseRun: admitted,