Re: [PATCH 02/19] x86/fpu: Prepare KVM for dynamically enabled states

From: Paolo Bonzini
Date: Mon Dec 13 2021 - 04:12:31 EST


On 12/8/21 01:03, Yang Zhong wrote:
- user_xfeatures

Track which features are currently enabled for the vCPU

Please rename to alloc_xfeatures

- user_perm

Copied from guest_perm of the group leader thread. The first
vCPU which does the copy locks the guest_perm

Please rename to perm_xfeatures.

- realloc_request

KVM sets this field to request dynamically-enabled features
which require reallocation of @fpstate

This field should be in vcpu->arch, and there is no need for fpu_guest_realloc_fpstate. Rename __xfd_enable_feature to fpu_enable_xfd_feature and add it to the public API, then just do

if (unlikely(vcpu->arch.xfd_realloc_request)) {
u64 request = vcpu->arch.xfd_realloc_request;
ret = fpu_enable_xfd(request, enter_guest);
}

to kvm_put_guest_fpu.

Paolo