Revert "FROMLIST: misc: fastrpc: fix UAF and kernel panic during clenup on process abort"

[Jianping (Jianping-Li)]

This reverts commit c3c6a80.

CRs-Fixed: 4630976

[qlijarvis]

🔨 Build Failure Analysis — PR #1630

PR: #1630
Build run: https://github.com/qualcomm-linux/kernel-config/actions/runs/30799209970

#	Error	File:Line	PR-introduced?	Root Cause
1	Merge conflict during automerge	drivers/misc/fastrpc.c	Yes	PR reverts commit c3c6a80 which conflicts with changes in topic/tech/mm/fastrpc branch
2	Merge conflict during automerge	sound/soc/qcom/sc8280xp.c	No	Pre-existing conflict unrelated to PR changes (PR only touches fastrpc.c)

Verdict

This is not a compilation failure. The build failed during the automerge step due to merge conflicts. 1 conflict is directly caused by this PR's revert; 1 conflict is pre-existing and unrelated to the PR changes.

📎 Detailed analysis: Full report

[qlijarvis]

🔨 Build Failure Analysis — PR #1630

PR: #1630
Build run: https://github.com/qualcomm-linux/kernel-config/actions/runs/30799209970

#	Error	File:Line	PR-introduced?	Root Cause
1	Merge conflict during automerge	drivers/misc/fastrpc.c	Yes	PR reverts commit c3c6a80 which conflicts with overlapping changes in topic branch topic/tech/mm/fastrpc
2	Merge conflict during automerge	sound/soc/qcom/sc8280xp.c	Indirect	Secondary conflict during integration, unrelated to PR's direct changes

Verdict

This is a merge conflict, not a compilation error. The build failed during the automerge/integration phase before any compilation occurred. Both conflicts are caused by this PR's revert operation conflicting with the topic branch topic/tech/mm/fastrpc. Resolution requires manual merge and coordination with the topic branch maintainer.

📎 Detailed analysis: Full report

[qlijarvis]

PR #1630 — validate-patch

PR: #1630

Verdict	Issues	Detailed Report
❌	8	Full report

Final Summary

1. Lore link present: No — Revert commit with no lore link or reference to original patch posting
2. Lore link matches PR commits: N/A — no lore link to compare against
3. Upstream patch status: N/A — This is a revert of a FROMLIST commit; original patch status unknown without lore link
4. PR present in qcom-next/topics: Yes - all 1 commit(s) are present in qcom-next or topics

Verdict: ❌ — click to expand

🔍 Patch Validation

PR: #1630 - Revert "FROMLIST: misc: fastrpc: fix UAF and kernel panic during cleanup on process abort"
Upstream commit: N/A (Revert commit - no lore link)
Verdict: ❌ FAIL

Commit Message

Check	Status	Note
Subject matches upstream	N/A	Revert commit - no upstream to compare
Body preserves rationale	❌	Missing revert justification
Fixes tag present/correct	❌	No explanation for why revert is needed
Authorship preserved	✅	Author is the submitter (revert author)
Backport note (if applicable)	N/A	Not a backport

Diff

File	Status	Notes
drivers/misc/fastrpc.c	⚠️	Reverts mutex protection and UAF fixes - no justification provided

Issues

Critical: Missing Revert Justification

• The commit message contains only "This reverts commit c3c6a80" with no explanation
• Kernel revert commits MUST include:
  • Why the original commit is being reverted (bug introduced, incorrect fix, etc.)
  • What problem the revert solves
  • Whether an alternative fix is planned
  • Any relevant bug reports, crash logs, or test failures

Missing Context for Original Commit

• The reverted commit c3c6a80 has a FROMLIST: prefix
• No lore.kernel.org link is provided to the original patch being reverted
• For a revert of a FROMLIST: commit, the commit message should reference the original lore posting

Technical Concern

• The revert removes mutex protection (sess->mutex) and UAF (use-after-free) fixes
• The original commit title explicitly mentions "fix UAF and kernel panic during cleanup"
• Reverting safety fixes without explanation is a red flag - this needs strong justification

Verdict

Do not merge without adding a proper commit message that explains:

1. What specific problem this revert solves (crash, regression, test failure)
2. Why the original UAF/panic fix approach was incorrect
3. Whether an alternative fix is planned or if the original issue no longer applies
4. Link to the original lore.kernel.org posting being reverted

Final Summary

1. Lore link present: No — Revert commit with no lore link or reference to original patch posting
2. Lore link matches PR commits: N/A — no lore link to compare against
3. Upstream patch status: N/A — This is a revert of a FROMLIST commit; original patch status unknown without lore link
4. PR present in qcom-next/topics: Yes — commit is present in topics branch (per integration_presence_report.md)

Deterministic Integration Presence

Integration Presence Report

This report is generated by Jarvis before validate-patch runs.
It is the authoritative source for whether PR changes are already present
in qcom-next or in the kernel topic branches.

Kernel repo: /local/mnt/workspace/sgaud/Qgenie/image_pipeline/kernel
qcom-next ref: 8d5dbc1b17adf8fe86a41adcda686785e73f5414
topics remote: topics -> https://github.com/qualcomm-linux/kernel-topics
topics fetch: fetched

Commit	Subject	qcom-next	topics	Final
1/1	[PATCH] Revert "FROMLIST: misc: fastrpc: fix UAF and kernel panic	partial - subject or partial tree evidence found, but full change was not verified	present - all checked added lines are present	present

Final Status

overall_status: PASS
present_commits: 1/1
partial_commits: 0/1
missing_commits: 0/1
topics_checked_for_commits: 1/1
final_summary: PR present in qcom-next/topics: Yes - all 1 commit(s) are present in qcom-next or topics

[qlijarvis]

PR #1630 — checker-log-analyzer

PR: #1630
Checker run: https://github.com/qualcomm-linux/kernel-config/actions/runs/30799210183

Checker	Result	Summary
Checker	Result	Summary
checkpatch	⚠️	CI infrastructure failure - merge failed
dt-binding-check	⚠️	CI infrastructure failure - merge failed
dtb-check	⚠️	CI infrastructure failure - merge failed
sparse-check	⚠️	CI infrastructure failure - merge failed
check-uapi-headers	⚠️	CI infrastructure failure - merge failed
check-patch-compliance	⚠️	CI infrastructure failure - merge failed
tag-check	⚠️	Cannot verify - CI did not complete

Detailed report: Full report

Checker analysis — click to expand

🤖 CI Checker Analysis (checker-log-analyzer)

PR: #1630 - Revert "FROMLIST: misc: fastrpc: fix UAF and kernel panic during cleanup on process abort"
Source: https://github.com/qualcomm-linux/kernel-config/actions/runs/30799210183

Checker	Result	Summary
checkpatch	⚠️	CI infrastructure failure - merge failed
dt-binding-check	⚠️	CI infrastructure failure - merge failed
dtb-check	⚠️	CI infrastructure failure - merge failed
sparse-check	⚠️	CI infrastructure failure - merge failed
check-uapi-headers	⚠️	CI infrastructure failure - merge failed
check-patch-compliance	⚠️	CI infrastructure failure - merge failed
tag-check	⚠️	Cannot verify - CI did not complete

---

⚠️ CI Infrastructure Failure

Root cause: Git merge failure with "refusing to merge unrelated histories" error during CI setup phase.

Failure details:

2026-08-03T09:11:44.7765360Z fatal: refusing to merge unrelated histories
2026-08-03T09:12:04.2691904Z Merging pr-1630 (no-commit)...
2026-08-03T09:12:24.0532558Z fatal: refusing to merge unrelated histories
2026-08-03T09:12:24.1652105Z Merge failed or conflicts detected. Aborting merge.

Analysis:

All six checker jobs failed during the CI setup phase before any actual checker validation could run. The failure occurred when the CI workflow attempted to:

1. Merge the baseline topic branch topic/tech/mm/fastrpc into an integration branch
2. Merge PR Revert "FROMLIST: misc: fastrpc: fix UAF and kernel panic during clenup on process abort" #1630 on top of that integration branch

Both merge operations failed with Git's "refusing to merge unrelated histories" error, which occurs when branches don't share a common ancestor.

This is a CI infrastructure/configuration issue, NOT a patch quality issue.

Possible causes:

• The PR branch (pr-1630) was created from a different base than expected
• The topic branch topic/tech/mm/fastrpc has diverged or been rebased
• The CI workflow is attempting to merge incompatible branch histories
• The PR may have been created against the wrong base branch

What was NOT tested:

• ❌ Checkpatch formatting validation
• ❌ Device tree binding validation
• ❌ DTB compilation and validation
• ❌ Sparse static analysis
• ❌ UAPI header ABI checks
• ❌ Patch compliance (prefix, Link, author)

Patch content (from pr.patch):
The PR is a revert commit that removes UAF (use-after-free) and kernel panic fixes from drivers/misc/fastrpc.c. The revert:

• Removes mutex protection from session contexts
• Removes allocated flag tracking
• Removes NULL checks before DMA operations
• Removes mutex-protected device validity checks

Subject line analysis:

Subject: [PATCH] Revert "FROMLIST: misc: fastrpc: fix UAF and kernel panic
         during cleanup on process abort"

⚠️ Missing prefix: The subject line does not start with a required prefix tag (FROMLIST:, UPSTREAM:, BACKPORT:, etc.). Revert commits must carry a prefix before the word "Revert".

Correct format should be:

UPSTREAM: Revert "FROMLIST: misc: fastrpc: fix UAF and kernel panic during cleanup on process abort"

or

FROMLIST: Revert "FROMLIST: misc: fastrpc: fix UAF and kernel panic during cleanup on process abort"

---

Recommended Actions

Immediate:

1. Fix the subject line prefix - Add UPSTREAM: or FROMLIST: before Revert in the commit message
2. Verify the PR base branch - Confirm PR Revert "FROMLIST: misc: fastrpc: fix UAF and kernel panic during clenup on process abort" #1630 is targeting the correct base branch (tech/mm/fastrpc)
3. Check branch history - Ensure the PR branch shares a common ancestor with the target branch
4. Re-trigger CI - After fixing the prefix, re-run the CI workflow

To fix the prefix:

git rebase -i HEAD~1   # mark commit as 'edit'
git commit --amend -m "UPSTREAM: Revert \"FROMLIST: misc: fastrpc: fix UAF and kernel panic during cleanup on process abort\""
git rebase --continue
git push --force-with-lease

To investigate the merge issue:

# Check if branches share common history
git merge-base origin/tech/mm/fastrpc HEAD

# If no common base, the PR may need to be rebased
git fetch origin tech/mm/fastrpc
git rebase origin/tech/mm/fastrpc

---

Verdict

Cannot merge - CI infrastructure failure prevented all checker validation. The patch itself cannot be evaluated until:

1. The subject line prefix is fixed (blocker)
2. The Git history/merge issue is resolved (blocker)
3. CI is successfully re-run with all checkers passing

Note: The revert itself removes safety features (mutex protection, NULL checks) that were added to fix UAF and kernel panics. Ensure there is a valid technical justification for this revert and that it has been reviewed by the fastrpc maintainers.