[PATCH 39/54] KVM: x86/mmu: Get nested MMU's root level from the MMU's role

From: Sean Christopherson
Date: Tue Jun 22 2021 - 14:02:56 EST


Initialize the MMU's (guest) root_level using its mmu_role instead of
redoing the calculations. The role_regs used to calculate the mmu_role
are initialized from the vCPU, i.e. this should be a complete nop.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/mmu/mmu.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 6c4655c356b7..6418b50d33ca 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4874,6 +4874,7 @@ static void init_kvm_nested_mmu(struct kvm_vcpu *vcpu)
g_context->get_guest_pgd = get_cr3;
g_context->get_pdptr = kvm_pdptr_read;
g_context->inject_page_fault = kvm_inject_page_fault;
+ g_context->root_level = new_role.base.level;

/*
* L2 page tables are never shadowed, so there is no need to sync
@@ -4890,19 +4891,14 @@ static void init_kvm_nested_mmu(struct kvm_vcpu *vcpu)
* the gva_to_gpa functions between mmu and nested_mmu are swapped.
*/
if (!is_paging(vcpu)) {
- g_context->root_level = 0;
g_context->gva_to_gpa = nonpaging_gva_to_gpa_nested;
} else if (is_long_mode(vcpu)) {
- g_context->root_level = is_la57_mode(vcpu) ?
- PT64_ROOT_5LEVEL : PT64_ROOT_4LEVEL;
reset_rsvds_bits_mask(vcpu, g_context);
g_context->gva_to_gpa = paging64_gva_to_gpa_nested;
} else if (is_pae(vcpu)) {
- g_context->root_level = PT32E_ROOT_LEVEL;
reset_rsvds_bits_mask(vcpu, g_context);
g_context->gva_to_gpa = paging64_gva_to_gpa_nested;
} else {
- g_context->root_level = PT32_ROOT_LEVEL;
reset_rsvds_bits_mask(vcpu, g_context);
g_context->gva_to_gpa = paging32_gva_to_gpa_nested;
}
--
2.32.0.288.g62a8d224e6-goog