News: 0001285076

  ARM Give a man a fire and he's warm for a day, but set fire to him and he's warm for the rest of his life (Terry Pratchett, Jingo)

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

([Operating Systems] 6 Hours Ago Vortex86)


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 [1]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.

[2]

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 [3]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.



[1] https://www.vortex86.com/news/2

[2] https://www.phoronix.com/image-viewer.php?id=2021&image=dmp_vortex86_linux_lrg

[3] https://lore.kernel.org/lkml/20211017094408.1512158-1-marcos@orca.pet/T/#u



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MEMORIES OF MY FAMILY MEETINGS still are a source of strength to me. I
remember we'd all get into the car -- I forget what kind it was -- and
drive and drive.

I'm not sure where we'd go, but I think there were some bees there. The
smell of something was strong in the air as we played whatever sport we
played. I remember a bigger, older guy whom we called "Dad." We'd eat
some stuff or not and then I think we went home.

I guess some things never leave you.
-- Jack Handey, The New Mexican, 1988.