On 2/8/21 8:16 AM, Jing Liu wrote: > -#define XSTATE_COMPACTION_ENABLED (1ULL << 63) > - > static void fill_xsave(u8 *dest, struct kvm_vcpu *vcpu) > { > struct xregs_state *xsave = &vcpu->arch.guest_fpu->state.xsave; > @@ -4494,7 +4492,8 @@ static void load_xsave(struct kvm_vcpu *vcpu, u8 *src) > /* Set XSTATE_BV and possibly XCOMP_BV. */ > xsave->header.xfeatures = xstate_bv; > if (boot_cpu_has(X86_FEATURE_XSAVES)) > - xsave->header.xcomp_bv = host_xcr0 | XSTATE_COMPACTION_ENABLED; > + xsave->header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT | > + xfeatures_mask_all; Are 'host_xcr0' and 'xfeatures_mask_all' really interchangeable? If so, shouldn't we just remove 'host_xcr0' everywhere?