Vortex86 Processors Finally Seeing Work In 2021 For Proper Handling Under Linux

The Vortex86 32-bit SoCs have worked under Linux for those distributions still maintaining 32-bit x86 support and where not hitting corner-cases of some i686 level features not being supported by some Vortex86 cores, but there is finally a pending kernel patch to provide proper CPU detection for Vortex86 hardware.

The DM&P Electronics Vortex86 SoCs work with various older Linux distributions just fine without catering the Linux kernel to these CPUs in not requiring any special handling compared to the generic x86 32-bit paths. This formal detection and support for DM&P Vortex processors being worked on now though in late 2021 is motivated by Spectre and Meltdown mitigations being incorrectly applied to them.

Vortex86 CPUs aren't vulnerable to Spectre and Meltdown since they are an in-order design and also lack the CLFLUSH instruction. But because the Linux kernel hasn't properly catered to Vortex86 and properly identified them, the performance-hitting mitigations were being incorrectly applied for those on these 32-bit SoCs that are slow enough as is without the unneeded mitigations.

Thus a patch is pending to provide support for properly recognizing DM&P Electronics Vortex86 processors so any quirks and tunings can be correctly applied. For now the only tuning / quirk handling just means Spectre and Meltdown mitigations will no longer be applied when booting on said hardware.