KVM: nVMX: Do not inherit quadrant and invalid for the root shadow EPT

Explicitly zero out quadrant and invalid instead of inheriting them from
the root_mmu.  Functionally, this patch is a nop as we (should) never
set quadrant for a direct mapped (EPT) root_mmu and nested EPT is only
allowed if EPT is used for L1, and the root_mmu will never be invalid at
this point.

Explicitly setting flags sets the stage for repurposing the legacy
paging bits in role, e.g. nxe, cr0_wp, and sm{a,e}p_andnot_wp, at which
point 'smm' would be the only flag to be inherited from root_mmu.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2019-03-07 15:27:43 -08:00 committed by Paolo Bonzini
parent 8c2ffd9174
commit 552c69b1dc

View File

@ -4918,11 +4918,15 @@ static union kvm_mmu_role
kvm_calc_shadow_ept_root_page_role(struct kvm_vcpu *vcpu, bool accessed_dirty,
bool execonly)
{
union kvm_mmu_role role;
union kvm_mmu_role role = {0};
union kvm_mmu_page_role root_base = vcpu->arch.root_mmu.mmu_role.base;
/* Base role is inherited from root_mmu */
role.base.word = vcpu->arch.root_mmu.mmu_role.base.word;
role.ext = kvm_calc_mmu_role_ext(vcpu);
/* Legacy paging and SMM flags are inherited from root_mmu */
role.base.smm = root_base.smm;
role.base.nxe = root_base.nxe;
role.base.cr0_wp = root_base.cr0_wp;
role.base.smep_andnot_wp = root_base.smep_andnot_wp;
role.base.smap_andnot_wp = root_base.smap_andnot_wp;
role.base.level = PT64_ROOT_4LEVEL;
role.base.direct = false;
@ -4930,6 +4934,7 @@ kvm_calc_shadow_ept_root_page_role(struct kvm_vcpu *vcpu, bool accessed_dirty,
role.base.guest_mode = true;
role.base.access = ACC_ALL;
role.ext = kvm_calc_mmu_role_ext(vcpu);
role.ext.execonly = execonly;
return role;