Emulator

What steps will reproduce the problem?

Disable MMU Emulation, then attempt a memory search using the memory widget starting from no address (the address 0 works too). When the search reaches address 0x40000000, FakeVMEM is detected as a valid RAM address by MMU::IsRAMAddress. However, AddressSpace::EffectiveAddressSpaceAccessors::Matches does not handle FakeVMEM properly despite a comment saying it should. As a result, a cascade of inescapable warnings occur, and even when ignored they effectively deadlock the process.

Is the issue present in the latest development version? For future reference, please also write down the version number of the latest development version.

Yes (Dolphin 2412-19)

Which is the first broken version?

The following change is to blame for this behavior: https://github.com/dolphin-emu/dolphin/pull/12193. This condition only handles locked L1 dcache, not FakeVMEM. A more robust solution is needed, as a reversion would break MEM2 again.