fix(ci): run the autofix scan lane on the persistent pool

.github/scripts/ci-runner-routing.test.mjs

@@ -1,4 +1,5 @@
-// Runner-routing regression guards for ci.yml and serve-ab.yml.
+// Runner-routing regression guards for ci.yml, serve-ab.yml, and the
+// qwen-autofix.yml scan lane.
 //
 // classify_pr carries the routing logic TWICE — the `runs-on` expression
 // (which selects the classify job's own runner) and the `pick_runner` shell
@@ -68,6 +69,13 @@ function evalRunsOn(expression, { ecsDisabled, eventName, sameRepo, assoc }) {
       /github\.event_name == 'merge_group'/,
       String(eventName === 'merge_group'),
     ],
+    // Longest term first as a convention; both patterns are quote-anchored
+    // (the closing quote is part of each regex), so neither can match
+    // inside the other and the substitution order is behaviorally inert.
+    [
+      /github\.event_name != 'pull_request_review'/,
+      String(eventName !== 'pull_request_review'),
+    ],
     [
       /github\.event_name != 'pull_request'/,
       String(eventName !== 'pull_request'),
@@ -80,6 +88,7 @@ function evalRunsOn(expression, { ecsDisabled, eventName, sameRepo, assoc }) {
       /contains\(fromJSON\('\["OWNER","MEMBER","COLLABORATOR"\]'\), github\.event\.pull_request\.author_association\)/,
       String(TRUSTED.includes(assoc)),
     ],
+    [/github\.repository == 'QwenLM\/qwen-code'/, 'true'],
   ];
   let expr = expression.replace(/^\$\{\{\s*/, '').replace(/\s*\}\}$/, '');
   for (const [term, value] of substitutions) {
@@ -421,3 +430,90 @@ describe('serve-ab.yml runner routing', () => {
     );
   });
 });
+
+describe('qwen-autofix.yml scan-lane runner routing', () => {
+  // route and review-scan gate the WHOLE fan-out: while they sit queued no
+  // review-address leg starts. A hosted-runner backlog queued them past the
+  // cron period, and the cron supersede rule then starved every scan round
+  // (2026-08-25) — so pin the lane on the persistent pool, with the
+  // fork-trust clause and the kill-switch intact.
+  const autofixDoc = parse(
+    readFileSync(join(workflowsDir, 'qwen-autofix.yml'), 'utf8'),
+  );
+  // evalRunsOn unwraps the winning fromJSON label to the array it names, so
+  // compare against arrays, not the ECS/HOSTED string constants above.
+  const ECS_LABELS = ['self-hosted', 'linux', 'x64', 'ecs-qwen'];
+  const HOSTED_LABELS = ['ubuntu-latest'];
+
+  for (const jobName of ['route', 'review-scan']) {
+    const runsOn = String(autofixDoc.jobs[jobName]['runs-on']);
+
+    it(`${jobName} reaches the persistent pool on schedule, dispatch, and issue_comment`, () => {
+      // issue_comment is route's /takeover and /retry lane — pin it beside
+      // the cron and dispatch triggers so a later event-allowlist narrowing
+      // of the pool clause cannot silently demote it back to hosted.
+      for (const eventName of [
+        'schedule',
+        'workflow_dispatch',
+        'issue_comment',
+      ]) {
+        assert.deepEqual(
+          evalRunsOn(runsOn, {
+            ecsDisabled: false,
+            eventName,
+            sameRepo: false,
+            assoc: '',
+          }),
+          ECS_LABELS,
+          `${jobName} must scan from the pool on ${eventName}`,
+        );
+      }
+    });
+
+    it(`${jobName} keeps untrusted fork PR lanes hosted`, () => {
+      for (const eventName of ['pull_request', 'pull_request_review']) {
+        assert.deepEqual(
+          evalRunsOn(runsOn, {
+            ecsDisabled: false,
+            eventName,
+            sameRepo: false,
+            assoc: 'NONE',
+          }),
+          HOSTED_LABELS,
+          `${jobName} fork lane (${eventName}) must stay hosted`,
+        );
+        assert.deepEqual(
+          evalRunsOn(runsOn, {
+            ecsDisabled: false,
+            eventName,
+            sameRepo: true,
+            assoc: 'NONE',
+          }),
+          ECS_LABELS,
+          `${jobName} same-repo lane (${eventName}) must reach the pool`,
+        );
+      }
+    });
+
+    it(`${jobName} obeys the kill-switch on every event`, () => {
+      for (const eventName of [
+        'schedule',
+        'workflow_dispatch',
+        'issue_comment',
+        'pull_request',
+        'pull_request_review',
+      ]) {
+        assert.deepEqual(
+          evalRunsOn(runsOn, {
+            ecsDisabled: true,
+            eventName,
+            sameRepo: true,
+            assoc: 'OWNER',
+          }),
+          HOSTED_LABELS,
+          `kill-switch must win on ${eventName}`,
+        );
+      }
+    });
+  }
+});

.github/workflows/.size-baseline

@@ -34,7 +34,7 @@
 6495 pr-self-report-label.yml
 9646 qwen-autofix-fork-bridge.yml
 5942 qwen-autofix-fork-signal.yml
-397656 qwen-autofix.yml
+404284 qwen-autofix.yml
 7061 qwen-ci-flaky-rerun.yml
 158010 qwen-code-pr-review.yml
 79041 qwen-fleet-shepherd.yml

.github/workflows/qwen-autofix.md

@@ -249,6 +249,7 @@ task-oriented guides — what a maintainer types and what happens next — see:
 - [145. review-address · Report dry-run / failure — CUMULATIVE timeout breaker — the sibling of the consecutive one above, for the…](#af-145)
 - [146. review-address · Report dry-run / failure — The agent committed (verify recorded committed=true before any gate could fail),…](#af-146)
 - [147. review-address · Report dry-run / failure — Same byte-budget hygiene as the English excerpt above. 3000 bytes ≈ 1000 CJK…](#af-147)
+- [148. route — Persistent pool, not hosted: a hosted backlog queued route past the cron period, and af-005's…](#af-148)
 
 ---
 
@@ -3727,3 +3728,43 @@ forbids HTML in failure.zh.md), but must not be able to open
 or close a <details>/<summary> that swallows the closing tag
 the workflow emits below.
 ```
+
+<a id="af-148"></a>
+
+### 148. route — Persistent pool, not hosted: a hosted backlog queued route past the cron period, and af-005's supersede then starved every scan round.
+
+In `route` and `review-scan`.
+
+```text
+route and review-scan run on the persistent pool, not the
+hosted one. They are short trusted base-repo jobs, but they
+gate the WHOLE fan-out: while they sit queued, no
+review-address leg starts. On 2026-08-25 a hosted-runner
+backlog queued route for over 20 minutes — longer than the
+cron period — and af-005's newer-tick-supersedes-older rule
+then cancelled every still-queued round: nine consecutive
+schedule runs died without scanning while the ecs-qwen pool
+stood mostly idle. The supersede rule stays — it is right
+once route gets a runner in seconds; the fix is taking the
+hosted queue out of the critical path. review-scan moves
+with it because it shares the gate, and its own hosted waits
+delayed every fan-out by the same backlog. Both keep the
+fork-trust clause of the sibling lanes: pull_request and
+pull_request_review resolve this file from the PR's own
+merge commit, so only same-repo heads and write-access
+authors may reach the persistent pool; everything else stays
+hosted, and the kill-switch wins everywhere. Neither job
+checks code out — route only decides phases, and review-scan
+only calls the API — so the shared workspace needs no
+restore or wipe step here. The pool still leaves two marks
+on the lane, both closed in the same change. One: gh reads
+its config from the shared, attacker-writable $HOME, so both
+steps carry the heavy jobs' gh hardening preamble — a planted
+~/.config/gh/config.yml could reroute their gh calls into a
+local socket, taking CI_DEV_BOT_PAT with the scan and forged
+collaborator-permission answers with route. Two: review-scan
+fills a per-run WORKDIR with API dumps that no VM teardown
+removes on the pool, so it gets a fixed autofix* per-run path
+(the age sweep can reclaim it after a hard kill), an EXIT
+trap, and an always() cleanup step mirroring issue-autofix.
+```

.github/workflows/qwen-autofix.yml

@@ -200,7 +200,10 @@ jobs:
     # Full rationale → qwen-autofix.md#af-004
     if: |-
       ${{ github.repository == 'QwenLM/qwen-code' && (github.event_name != 'issue_comment' || (github.event.issue.pull_request && (startsWith(github.event.comment.body, '@qwen-code /takeover') || startsWith(github.event.comment.body, '@qwen-code /retry')))) && (github.event_name != 'pull_request' || github.event.label.name == 'autofix/takeover') && (github.event_name != 'pull_request_review' || github.event.pull_request.state == 'open') }}
-    runs-on: 'ubuntu-latest'
+    # Persistent pool, not hosted: a hosted backlog queued route past the cron
+    # period, and af-005's supersede then starved every scan round.
+    # Full rationale → qwen-autofix.md#af-148
+    runs-on: '${{ (github.repository == ''QwenLM/qwen-code'' && vars.MAINTAINER_ECS_RUNNER_DISABLED != ''true'' && (github.event_name != ''pull_request'' && github.event_name != ''pull_request_review'' || github.event.pull_request.head.repo.full_name == github.repository || contains(fromJSON(''["OWNER","MEMBER","COLLABORATOR"]''), github.event.pull_request.author_association))) && fromJSON(''["self-hosted", "linux", "x64", "ecs-qwen"]'') || fromJSON(''["ubuntu-latest"]'') }}'
     timeout-minutes: 5
     concurrency:
       # Concurrency is keyed by TARGET, not shared and not fully unique:
@@ -256,6 +259,15 @@ jobs:
           COMMENT_PR_AUTHOR: '${{ github.event.issue.user.login }}'
           HAS_PR_URL: '${{ github.event.issue.pull_request.url }}'
         run: |-
+          # gh has its own reroute channels: pin the host, drop planted tokens,
+          # and point gh at a fresh empty config dir — on the persistent pool
+          # the shared ~/.config/gh is attacker-writable (config.yml can carry
+          # http_unix_socket transport reroutes), and a forged collaborator-
+          # permission response here would open the /takeover and /retry gates.
+          # Mirrors the heavy jobs' preamble. Full rationale → qwen-autofix.md#af-148
+          export GH_HOST=github.com
+          unset GH_ENTERPRISE_TOKEN GH_TOKEN
+          export GH_CONFIG_DIR="$(mktemp -d "${RUNNER_TEMP}/autofix-gh-config.XXXXXX")"
           DO_ISSUE=false
           DO_REVIEW=false
           TAKEOVER_ACK=''
@@ -2054,7 +2066,8 @@ jobs:
     needs: 'route'
     if: |-
       ${{ needs.route.outputs.do_review == 'true' }}
-    runs-on: 'ubuntu-latest'
+    # Same pool decision as route. Full rationale → qwen-autofix.md#af-148
+    runs-on: '${{ (github.repository == ''QwenLM/qwen-code'' && vars.MAINTAINER_ECS_RUNNER_DISABLED != ''true'' && (github.event_name != ''pull_request'' && github.event_name != ''pull_request_review'' || github.event.pull_request.head.repo.full_name == github.repository || contains(fromJSON(''["OWNER","MEMBER","COLLABORATOR"]''), github.event.pull_request.author_association))) && fromJSON(''["self-hosted", "linux", "x64", "ecs-qwen"]'') || fromJSON(''["ubuntu-latest"]'') }}'
     timeout-minutes: 15
     # A forced scan can write the same status comment as review-address.
     # Share its per-PR lock so neither writer can erase the other's state.
@@ -2072,6 +2085,11 @@ jobs:
       enum_failed: '${{ steps.scan.outputs.enum_failed }}'
     env:
       REPO: '${{ github.repository }}'
+      # Per-run home for the scan's API dumps. A fixed autofix* name (not
+      # mktemp's tmp.*) so the age sweep in the heavy jobs can reclaim it
+      # after a hard runner kill; cleaned normally by the always() step.
+      # Full rationale → qwen-autofix.md#af-148
+      WORKDIR: '/tmp/autofix-scan-${{ github.run_id }}'
     steps:
       - name: 'Scan for PRs with new feedback'
         id: 'scan'
@@ -2083,6 +2101,16 @@ jobs:
           REVIEW_SENDER: '${{ needs.route.outputs.review_sender }}'
           DISPATCH_SOURCE: "${{ github.event_name == 'workflow_dispatch' && inputs.source || '' }}"
         run: |-
+          # gh reroute hardening, mirroring the heavy jobs: pin the host, drop
+          # planted tokens, and use a fresh empty config dir — the pool's
+          # shared ~/.config/gh is attacker-writable, and a config.yml with an
+          # http_unix_socket reroute would swallow this step's gh calls,
+          # CI_DEV_BOT_PAT in the Authorization header included.
+          # Full rationale → qwen-autofix.md#af-148
+          export GH_HOST=github.com
+          unset GH_ENTERPRISE_TOKEN GH_TOKEN
+          export GH_CONFIG_DIR="$(mktemp -d "${RUNNER_TEMP}/autofix-gh-config.XXXXXX")"
+
           # Every lane that reaches this scan is supposed to hold the PAT:
           # route now declines the one event GitHub is known to run without
           # secrets (a fork PR's own review) before it can set do_review.
@@ -2092,17 +2120,28 @@ jobs:
             exit 1
           fi
 
+          # Pre-clean before create, mirroring the heavy jobs: run_id is
+          # public and sequential, and mkdir -p alone would succeed over a
+          # dir or symlink pre-planted on the shared pool /tmp — the scan's
+          # redirects would then land in an attacker-chosen place, and a
+          # planted bot-prs.json would feed the forced-PR guard below.
+          rm -rf "${WORKDIR}"
+          (umask 077; mkdir -p "${WORKDIR}")
+
           # Fleet visibility: every per-PR decision below also records a row so
           # the run summary shows the WHOLE managed fleet in one table.
           # Reconstructing this by hand (list bot PRs, regex each one's eval
           # markers, cross-check checks and fork state) was the only way to see
           # a stall, so stalls stayed invisible until someone went looking.
-          FLEET_FILE="$(mktemp)"
-          trap 'rm -f "${FLEET_FILE}"' EXIT
+          # Inside WORKDIR, not mktemp's /tmp/tmp.*: on a cancelled run the
+          # EXIT trap never fires, and only the always() step and the heavy
+          # jobs' autofix* age sweep reclaim what this step leaves — neither
+          # can reach a tmp.* name.
+          FLEET_FILE="${WORKDIR}/fleet.tsv"
+          trap 'rm -f "${FLEET_FILE}"; rm -rf "${WORKDIR}"' EXIT
           fleet_row() {
             printf '%s\t%s\t%s\n' "$1" "$2" "$3" >> "${FLEET_FILE}"
           }
-          WORKDIR="$(mktemp -d)"
 
           read_forced_pr_meta() {
             local attempt meta
@@ -3264,6 +3303,16 @@ jobs:
           echo "targets=${TARGETS}" >> "${GITHUB_OUTPUT}"
           echo "has_targets=$([[ "${COUNT}" -gt 0 ]] && echo true || echo false)" >> "${GITHUB_OUTPUT}"
 
+      # Nothing else removes the per-run WORKDIR; on the persistent pool
+      # every scan would leave its API dumps behind forever. always() covers
+      # cancellation (the in-step EXIT trap does not fire on a killed run);
+      # only a hard runner kill abandons the dir, and the autofix* age sweep
+      # in the heavy jobs reclaims it. Mirrors issue-autofix's cleanup step.
+      # Full rationale → qwen-autofix.md#af-148
+      - name: 'Clean up scan workdir'
+        if: 'always()'
+        run: 'rm -rf "${WORKDIR}"'
+
   # ===========================================================================
   # REVIEW PHASE (build) — compile the trusted-base CLI bundle ONCE per scan
   # and fan it out to the address legs as an artifact. Each leg otherwise