[https://nvbugs/5875522][docs] Add known issue for disaggregated serving hang with asymmetric PP/TP

[Tabrizian]

Summary by CodeRabbit

• Documentation
  • Added Known Issue in Release Notes 1.2: Disaggregated Serving may hang in PyExecutor when using context pipeline parallelism and generation tensor parallelism configurations.

Description

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[coderabbitai]

📝 Walkthrough

Walkthrough

Added a new Known Issue entry to Release Notes 1.2 documenting that Disaggregated Serving may hang in PyExecutor during disaggregated serving with specific pipeline parallelism and tensor parallelism configurations. Documentation-only change.

Changes

Cohort / File(s)	Summary
Release Notes Documentation docs/source/release-notes.md	Added Known Issue entry for Release Notes 1.2 regarding potential PyExecutor hangs in disaggregated serving with context pipeline parallelism and generation tensor parallelism.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The PR description is entirely blank with no content provided in any required sections (Description, Test Coverage, or PR Checklist details).	Fill in the Description section explaining what known issue is being added and why. Complete the Test Coverage section if applicable, and provide details supporting the PR Checklist items.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly specifies the change: adding a known issue about disaggregated serving hang with asymmetric PP/TP, which matches the changelog update in the PR.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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✨ Finishing Touches

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[Tabrizian]

/bot skip --comment "release note"

[tensorrt-cicd]

PR_Github #37100 [ skip ] triggered by Bot. Commit: 4f92ed0 Link to invocation

[tensorrt-cicd]

PR_Github #37100 [ skip ] completed with state SUCCESS. Commit: 4f92ed0
Skipping testing for commit 4f92ed0

Link to invocation