Multiprocess operations can lead to spinner deadlock

Metadata

Project: craft-cli
Number: #172
Type: issue
State: open
Author: cmatsuoka
Labels: —
Created: 2023-08-25 01:23 PM UTC
Updated: 2023-08-25 01:23 PM UTC
Closed: —

Current evaluation

Deadlock when a multiprocess overlay chroot subprocess writes an info message while the CLI spinner thread is active. Stub report, no labels or comments in 3 years. Referenced craft-parts PR #535 merged to mitigate by downgrading overlay logging to debug.

Suggested action: close stale

Reason: The issue is a 3-year-old stub (TODO reproduction steps, no labels, zero comments) and the referenced craft-parts PR #535 was merged specifically to prevent this terminal deadlock by downgrading overlay package logging from info to debug, so the reported trigger is no longer applicable. The broader spinner/multiprocess interaction may still be worth tracking, but this issue as filed has been addressed and never developed into a reproducible report.

Impact: 45 Quick Win: 13.5 Staleness: 88 Complexity: 70 Confidence: 60 Support Request: 5

Issue body

### Bug Description There is a bad interaction between the way we perform overlay operations (a chroot in a multiprocess-created subprocess) and the way craft applications indicate progress on the cli (a spinner in a thread). The consequence of the bad interaction is that trying to write an info message to the terminal ends up deadlocking the main thread in the subprocess because the thread that could unblock it does not exist. See https://github.com/canonical/craft-parts/pull/535. ### To Reproduce TODO ### part yaml _No response_ ### Relevant log output ```shell TODO ```

Evaluation history

Date	Model	Scores	Action	Summary
2026-09-01 04:51 AM UTC	qwen/qwen3.8-27b	Impact: 45 Quick Win: 13.5 Staleness: 88 Complexity: 70 Confidence: 60 Support Request: 5	close stale	Deadlock when a multiprocess overlay chroot subprocess writes an info message while the CLI spinner thread is active. Stub report, no labels or comments in 3 years. Referenced craft-parts PR #535 merged to mitigate by downgrading overlay logging to debug.
2026-07-22 12:16 PM UTC	qwen/qwen3.6-35b-a3b	Staleness: 95 Complexity: 65 Confidence: 85 Support Request: 5	close stale	Multiprocess overlay operations can deadlock the CLI progress spinner thread in a subprocess. Reported ~3 years ago with no reproduction steps, labels, or maintainer follow-up. Currently untriaged and inactive.
2026-07-09 03:07 AM UTC	qwen3.6-35b-a3b-mtp-q6	Staleness: 95 Complexity: 75 Confidence: 85 Support Request: 5	needs triage	Multiprocess overlay operations deadlock CLI spinner threads. Reported by a maintainer nearly three years ago with no reproduction steps, labels, or maintainer comments. Requires assessment to determine if referenced PRs resolved it or if it remains relevant.
2026-06-17 12:09 PM UTC	qwen3.6-35b-a3b-mtp-q6	Staleness: 95 Complexity: 45 Confidence: 85 Support Request: 10	close stale	Multiprocess overlay operations deadlock the main subprocess thread when interacting with the CLI spinner. Currently unassigned with no comments or reproduction steps, requiring triage to resolve the thread synchronization bug.

Update history

No update history recorded yet.

Related work

Likely Fixed By: craft-parts#535 (confidence 85%)
Merged PR 'packages: don't write info logs in overlays' downgrades overlay logging to debug to prevent terminal deadlocks during chroot subprocess operations — the exact failure mode described in this issue.

Related issues

No related issues found above the similarity threshold.