Upstream PR 3028 Precise TB Invalidation

Upstream PR #3028 — Avoid whole-page TB invalidation for same-page stores

Upstream work · Actionable research · Research and retired work

Current disposition — November 1, 2026

Reviewed: November 1, 2026. Fork source: b7140848 (full SHA b71408480a3a979a9c584663e1d1f400904c8bb7). Latest stable checked: v0.8.136-0-g458730bf5373, September 30, source 458730bf5373f1f0d027450fef7443e3af7a3ae1. GitHub state, branch recommendation, source presence and release availability are separate facts. See current status and release versus main.

Current field	November 1, 2026 observation
GitHub source	Upstream #3028
GitHub state / draft	Open / No
Current head	792e00bd42bd078a2f26e132d1da41cb4389a006
Originally reviewed head	Not recorded on original page
Last metadata update (UTC)	2026-10-18T20:59:11Z
Head versus original review	Original page did not record a head; code-change comparison is not established.
Current action	Recover original self-page/SmartXX reproducer before qualification.
Fork/release availability	Fork #317 is unmerged and absent from pinned main/stable; the opportunity still requires its original reproducer.

Upstream remains open. Fork #317 is open but SKIPPED/HOLD: recover the original own-current-TB/self-page guest source/XBE and #42/SmartXX loader recipe. Current PGR2 and Conker diagnostic scenes contain zero eligible current-page events. Maintained other-writer/stable-code tests are controls, not substitutes for the missing own-page reproducer; repeating unchanged zero-exposure games will not qualify it.

This refresh checked GitHub identity/state and the specific source boundaries named above. It did not rerun native games, XISO timings or integration qualification. Historical performance claims remain attached to their original heads.

Historical review — September 21, 2026

The review below is preserved as written, including its original state, head, fork baseline and proposed handoff. Its present-tense statements apply to that dated review; the current disposition above governs today’s action.

← Upstream Work In Need

Field	Value
Upstream PR	xemu-project/xemu#3028
Audit state	Focused CPU experiment; refresh before implementation
Fork baseline reviewed	82d04d84bdb3de956f20c3537e1da2cece0e8da2

Candidate

Use precise translation-block overlap checking for a store on the page occupied by the executing block, instead of invalidating every same-page write.

Required proof

• Unrelated same-page data stores avoid needless invalidation.
• Writes that modify executing instructions still invalidate correctly.
• Two-page blocks and writes without a current CPU preserve existing behavior.
• Count invalidations, retranslations, and guest progress on exact heads.

This is not a request to broaden TCG invalidation semantics. Its value depends on measured same-page stores that do not overlap translated instructions.

References

• Upstream PR #3028
• Upstream Work In Need
• CPU and vCPU Execution