On Mon, Feb 27, 2023 at 09:05:24PM +0000, Takahiro Itazuri wrote:
> VMMs retrieve supported CPUID features via KVM_GET_SUPPORTED_CPUID to
> construct CPUID information to be passed to KVM_SET_CPUID2. Most CPUID
> feature bits related to speculative attacks are propagated from host
> CPUID. But AMD processors have AMD-specific IBRS related bits in CPUID
> Fn8000_0008_EBX (ref: AMD64 Architecture Programmer's Manual Volume 3:
> General-Purpose and System Instructions) and some bits are not
> propagated to guests.
>
> Enable propagation of these bits to guests, so that VMMs don't have to
> enable them explicitly based on host CPUID.
How hard is it for the VMMs to enable them?
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
