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NousResearch/hermes-agent

Fix segfault from unsynchronized SessionDB reads during close

Cluster 99349. Data as of

Nothing open on GitHub. Fix merged in #99502 on 31 Aug 2026. Check it covers your case.

The short answer

0open issues
0open PRs
4items grouped
Known?
Yes. 4 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #99502. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #99502. That is separate from the fix event.
Still open
Nothing open on GitHub.

These issues and PRs address a SIGSEGV/SystemError caused by lock-free SessionDB reads racing with Connection.close() inside pysqlite's statement cache. The proposed fixes involve serializing or routing reads to eliminate unsynchronized access on the shared writer connection.

Open issues0

No open issues.

Open PRs0

No open pull requests.

Fixes on record

Merged to main. A stamp counts the issues a fix is linked to.

  • #99502 fix(state): eliminate unsynchronized reads on the shared SessionDB writer connection (SIGSEGV / SystemError class)

    merged to main

    files: hermes_state.py, hermes_state_search.py, tests/state/test_writer_conn_thread_safety.py, tests/test_hermes_state_conn_lock_audit.py, tests/test_session_db_read_path_split.py

2 PRs closed without merging

From the close comments: done elsewhere 1 · merged via another change 1

  • #99366 fix(sessions): serialize SessionDB reads during close · done elsewhere → #99502
  • #99435 fix(state): route lock-free SessionDB reads through _read_ctx (segfault racing close()) · merged via another change → #99349, #82428
Closed issues · 1
  • Closed#99349SIGSEGV: lock-free SessionDB reads race Connection.close() inside pysqlite's statement cache
How this cluster was grouped
  • Link evidence (structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
  • Pairwise link density 0.50: the share of item pairs that carry a link, counting a structural link in full and a relevance-only link at 0.36. 1.00 means every pair is linked.

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At a glance

Merged PRs
#99502
Closed issues
1
Attempts
2 PRs closed without merging
Fix link checked
31 Aug 2026

For your agent

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