Fix PR creation stage

Signed-off-by: Shreeya Patel <spatel@ciq.com>

Author: shreeya-patel98

.github/workflows/kernel-build-and-test-x86_64.yml

@@ -199,12 +199,13 @@ jobs:
     if: success() || failure()
     outputs:
       base_branch: ${{ steps.base_branch.outputs.base_branch }}
+      comparison_status: ${{ steps.comparison.outputs.comparison_status }}
 
     steps:
     - name: Checkout kernel source
       uses: actions/checkout@v4
       with:
-        fetch-depth: 0
+        fetch-depth: 100  # Enough depth for finding merge-base with parent branch
 
     - name: Download current kselftest logs
       uses: actions/download-artifact@v4
@@ -359,15 +360,23 @@ jobs:
     if: success() || failure()
 
     steps:
-    - name: Check if all stages passed
+    - name: Check if tests passed and no regressions
       run: |
+        # Skip PR if any test stage failed
         if [ "${{ needs.build.result }}" != "success" ] || \
            [ "${{ needs.boot.result }}" != "success" ] || \
            [ "${{ needs.test-kselftest.result }}" != "success" ]; then
           echo "One or more test stages failed, skipping PR creation"
           exit 1
         fi
-        echo "All test stages passed, proceeding with PR creation"
+
+        # Skip PR if regression was detected (but allow if comparison was skipped/unavailable)
+        if [ "${{ needs.compare-results.outputs.comparison_status }}" = "failed" ]; then
+          echo "Test regression detected, skipping PR creation"
+          exit 1
+        fi
+
+        echo "All test stages passed and no regressions detected, proceeding with PR creation"
 
     - name: Checkout kernel source
       uses: actions/checkout@v4