Re: [PATCH] KVM: x86: add hint to skip hidden rdpkru under kvm_load_host_xsave_state

[Dave Hansen]

On 5/7/21 9:52 AM, Paolo Bonzini wrote:
> This can be optimized as well, can't it?  This means that the only case
> that needs the rdpkru is in switch_fpu_finish, and __write_pkru can be
> removed completely:
> 
> - do the rdpkru+wrpkru in switch_fpu_finish
> 
> - just use wrpkru in KVM

I was going to suggest exactly the same thing.  It doesn't require the
compiler to be smart, and wrpkru() is available in the same header as
__write_pkru().

I also detest the mysterious true/false arguments to functions where you
have no clue what they're doing at the call site without comments.