Re: [PATCH v2 0/4] x86, fpu/kvm: fix crash with AMX

[Borislav Petkov]

On Thu, Jan 01, 2026 at 10:05:12AM +0100, Paolo Bonzini wrote:
> Fix a possible host panic, due to an unexpected #NM, when a KVM guest
> is using AMX features.
> 
> The guest's XFD value, which is stored in fpstate->xfd, is used for both
> guest execution and host XSAVE operations. 

This already sounds weird. Why?

Why don't we carry separate XFD copies - guest and host - which we use for the
guest and the host, respectively?

-- 
Regards/Gruss,
    Boris.

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