Fix kselftest and PR creation errors

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

Author: shreeya-patel98

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

@@ -199,6 +199,11 @@ jobs:
     if: success() || failure()
 
     steps:
+    - name: Checkout kernel source
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+
     - name: Download current kselftest logs
       uses: actions/download-artifact@v4
       with:
@@ -208,33 +213,62 @@ jobs:
     - name: Determine base branch for comparison
       id: base_branch
       run: |
-        # Determine base branch from the upstream tracking branch
-        BASE_BRANCH=$(git rev-parse --abbrev-ref --symbolic-full-name @{u} 2>/dev/null | sed 's|^origin/||' || echo "")
+        BASE_BRANCH=""
 
-        if [ -z "$BASE_BRANCH" ]; then
-          # Fallback: use merge-base to find the common ancestor branch
-          echo "No upstream tracking branch found, using merge-base to find parent branch"
-          for branch in lts-9.2 lts-9 main master; do
-            if git rev-parse origin/$branch >/dev/null 2>&1; then
-              MERGE_BASE=$(git merge-base HEAD origin/$branch 2>/dev/null || echo "")
-              if [ -n "$MERGE_BASE" ]; then
-                BASE_BRANCH=$branch
-                echo "Found common ancestor with origin/$branch"
-                break
+        # For PRs, use the base branch directly
+        if [ -n "${{ github.base_ref }}" ]; then
+          BASE_BRANCH="${{ github.base_ref }}"
+          echo "Using PR base branch: $BASE_BRANCH"
+        else
+          # For direct pushes, find the common ancestor branch
+          echo "Not a PR, finding base branch via merge-base"
+
+          # Get all remote branches and find the one with closest common ancestor
+          CURRENT_COMMIT=$(git rev-parse HEAD)
+          BEST_BRANCH=""
+          CLOSEST_DISTANCE=999999
+
+          for remote_branch in $(git for-each-ref --format='%(refname:short)' refs/remotes/origin/ | grep -v 'HEAD\|PR-CHECKER'); do
+            branch_name=$(echo "$remote_branch" | sed 's|^origin/||')
+
+            # Skip if it's the current branch
+            if [ "$branch_name" = "${{ github.ref_name }}" ]; then
+              continue
+            fi
+
+            MERGE_BASE=$(git merge-base HEAD "$remote_branch" 2>/dev/null || echo "")
+
+            # Check if this branch shares history and isn't the current commit
+            if [ -n "$MERGE_BASE" ] && [ "$MERGE_BASE" != "$CURRENT_COMMIT" ]; then
+              # Calculate distance (number of commits) from merge-base to current HEAD
+              DISTANCE=$(git rev-list --count ${MERGE_BASE}..HEAD 2>/dev/null || echo "999999")
+
+              # Find the branch with the shortest distance (most recent common ancestor)
+              if [ "$DISTANCE" -lt "$CLOSEST_DISTANCE" ]; then
+                CLOSEST_DISTANCE=$DISTANCE
+                BEST_BRANCH=$branch_name
               fi
             fi
           done
+
+          if [ -n "$BEST_BRANCH" ]; then
+            BASE_BRANCH=$BEST_BRANCH
+            echo "Found common ancestor with $BASE_BRANCH (distance: $CLOSEST_DISTANCE commits)"
+          fi
         fi
 
         if [ -z "$BASE_BRANCH" ]; then
-          echo "WARNING: Could not determine base branch, defaulting to main"
-          BASE_BRANCH="main"
+          echo "::warning::Could not determine base branch for comparison - no common ancestor found"
+          echo "::warning::Kselftest comparison will be skipped"
+          echo "base_branch=" >> $GITHUB_OUTPUT
+          exit 0
         fi
 
         echo "base_branch=$BASE_BRANCH" >> $GITHUB_OUTPUT
         echo "Base branch for comparison: $BASE_BRANCH"
 
     - name: Download baseline kselftest logs from base branch
+      if: steps.base_branch.outputs.base_branch != ''
       uses: dawidd6/action-download-artifact@v3
       with:
         workflow: kernel-build-and-test-x86_64.yml
@@ -250,6 +284,15 @@ jobs:
     - name: Compare test results
       id: comparison
       run: |
+        # Check if we have a base branch to compare against
+        if [ -z "${{ steps.base_branch.outputs.base_branch }}" ]; then
+          echo "::warning::No base branch found for comparison"
+          echo "::warning::Kselftest comparison will be skipped"
+          echo "comparison_status=skipped" >> $GITHUB_OUTPUT
+          echo "comparison_message=No base branch found - unable to determine merge target" >> $GITHUB_OUTPUT
+          exit 0
+        fi
+
         # Check if baseline logs exist
         if ls output-previous/kselftests-*.log 1> /dev/null 2>&1; then
           # Compare passing tests (ok)
@@ -396,22 +439,48 @@ jobs:
       env:
         GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       run: |
-        # Determine base branch from the upstream tracking branch
-        BASE_BRANCH=$(git rev-parse --abbrev-ref --symbolic-full-name @{u} 2>/dev/null | sed 's|^origin/||' || echo "")
+        BASE_BRANCH=""
 
-        if [ -z "$BASE_BRANCH" ]; then
-          # Fallback: use merge-base to find the common ancestor branch
-          echo "No upstream tracking branch found, using merge-base to find parent branch"
-          for branch in lts-9.2 lts-9 main master; do
-            if git rev-parse origin/$branch >/dev/null 2>&1; then
-              MERGE_BASE=$(git merge-base HEAD origin/$branch 2>/dev/null || echo "")
-              if [ -n "$MERGE_BASE" ]; then
-                BASE_BRANCH=$branch
-                echo "Found common ancestor with origin/$branch"
-                break
+        # For PRs, use the base branch directly
+        if [ -n "${{ github.base_ref }}" ]; then
+          BASE_BRANCH="${{ github.base_ref }}"
+          echo "Using PR base branch: $BASE_BRANCH"
+        else
+          # For direct pushes, find the common ancestor branch
+          echo "Not a PR, finding base branch via merge-base"
+
+          # Get all remote branches and find the one with closest common ancestor
+          CURRENT_COMMIT=$(git rev-parse HEAD)
+          BEST_BRANCH=""
+          CLOSEST_DISTANCE=999999
+
+          for remote_branch in $(git for-each-ref --format='%(refname:short)' refs/remotes/origin/ | grep -v 'HEAD\|PR-CHECKER'); do
+            branch_name=$(echo "$remote_branch" | sed 's|^origin/||')
+
+            # Skip if it's the current branch
+            if [ "$branch_name" = "${{ github.ref_name }}" ]; then
+              continue
+            fi
+
+            MERGE_BASE=$(git merge-base HEAD "$remote_branch" 2>/dev/null || echo "")
+
+            # Check if this branch shares history and isn't the current commit
+            if [ -n "$MERGE_BASE" ] && [ "$MERGE_BASE" != "$CURRENT_COMMIT" ]; then
+              # Calculate distance (number of commits) from merge-base to current HEAD
+              DISTANCE=$(git rev-list --count ${MERGE_BASE}..HEAD 2>/dev/null || echo "999999")
+
+              # Find the branch with the shortest distance (most recent common ancestor)
+              if [ "$DISTANCE" -lt "$CLOSEST_DISTANCE" ]; then
+                CLOSEST_DISTANCE=$DISTANCE
+                BEST_BRANCH=$branch_name
               fi
             fi
           done
+
+          if [ -n "$BEST_BRANCH" ]; then
+            BASE_BRANCH=$BEST_BRANCH
+            echo "Found common ancestor with $BASE_BRANCH (distance: $CLOSEST_DISTANCE commits)"
+          fi
         fi
 
         if [ -z "$BASE_BRANCH" ]; then