MMU: Use VSID in segment register as additional TLB lookup key

[Wack0]

The current TLB implementation does not use the VSID at all.

This is incorrect behaviour (I think the diagram on A Quick Introduction to the PPC Memory Management System explained the correct behaviour easily for me).

The incorrect behaviour leads to previously cached pages still being used until they are flushed out of the TLB, which could lead to an application or game reading or writing to the "wrong" pages.

[JosJuice]

Because you changed the layout of TLBEntry, which is included in savestates, you need to increment the savestate version number in State.cpp.

[Wack0]

That makes sense. Do I need to squash the commits, or is that done automatically when merging?

[AdmiralCurtiss]

You need to squash and force-push yourself.

[Wack0]

OK, done.

[abyssfan]

🕵️‍♀️ Excuse me. This is a violation of the contribution legal requirements. Zammis Clark, aka wack0 and riley, is a notorious Nintendo hacker. He hacked Nintendo in 2018 and is the original source of all of the Nintendo files that leaked out in 2020. That included many GameCube and Wii files if you want to try and handwave away that stuff as being unrelated.

You've now tainted the repository with two of his pull requests.

[Tilka]

@abyssfan Thanks for your concern. Vetting contributions with extra care increases the review burden, but all of @Wack0's pull requests so far have been well explained and clearly limited to the publicly documented PowerPC architecture (try searching for VSID, DSISR, or SRR0). So no, nothing is tainted.

@Wack0 Assuming the allegations are true, I do request that you continue to provide full provenance for your contributions.

[JosJuice]

@Wack0 Assuming the allegations are true, I do request that you continue to provide full provenance for your contributions.

That isn't what our policy is. The policy is that if you have looked at Nintendo documentation related to the GameCube and Wii (which I should add is not quite the same thing as @abyssfan's allegation – leaking is not the same as looking, and I think it's unlikely that any single person would have looked at everything there is in the gigaleak considering what I've heard about its size), we ask you to not contribute code.