The workaround for bootupd detection issue (bootc#1778) works on all architectures except s390x. Investigate the root cause and determine if this requires a bootc fix or should be documented as a known issue.

Background:

• GitHub issue bootc#1778: Regression with bootupd detection
• Workaround: Add --bootloader grub flag (but only for non-s390x architectures)
• Colin Walters noted complications with hardcoding bootloader for s390x
• Issue is closed upstream, but s390x limitation remains
• Anaconda team raised concerns about multi-arch quality (Dec 12, 2025 meeting)

Investigation Steps:
1. Review bootc#1778 and the merged PR#1785
2. Test bootc installation on s390x with current workaround
3. Test alternative approaches (if any)
4. Consult with Colin Walters on s390x bootloader requirements
5. Coordinate with Anaconda team on their s390x testing results

Decision Required:

• Is this a RHEL 10.2 release blocker? (Current answer: No, but needs confirmation)
• Should we fix before GA or document as known issue?
• What's the timeline for a proper fix?

Note:
Per meeting discussion, this is not currently considered a release blocker since bootc supports all 4 architectures and installer-specific s390x limitation can be documented as a known issue.

Acceptance Criteria:

• Reproduce the s390x issue in test environment
• Document the specific failure mode
• Determine if this is a bootc bug that needs fixing, an Anaconda integration issue, or a known limitation to document
• If it's a bootc bug: File detailed bug report with reproduction steps
• If it's a known limitation: Document in release notes
• Coordinate with Colin Walters and Anaconda team on resolution path