Re: Hang when booting guest kernels compiled with clang after SRSO mitigations

From: Borislav Petkov
Date: Fri Aug 11 2023 - 12:12:45 EST


On Fri, Aug 11, 2023 at 09:03:18AM -0700, Sean Christopherson wrote:
> Might be the flags bug that borks KVM's fastop() emulation. If that fixes things,
> my guess is that bringing APs out of WFS somehow triggers emulation.

I was just about to connect you two guys, thanks Sean!

> https://lore.kernel.org/all/20230811155255.250835-1-seanjc@xxxxxxxxxx

Nathan, if you could test, that would be cool.

Also, Nick has another patch for -mno-shared, it probably isn't fixing
yours but it would be good to test it too, just in case:

https://github.com/ClangBuiltLinux/linux/issues/1911#issuecomment-1674993796

Thx!

--
Regards/Gruss,
Boris.

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