2023-01-12 17:22:38

by Isaku Yamahata

[permalink] [raw]
Subject: [RFC PATCH v3 16/16] KVM: TDX: Allow 2MB large page for TD GUEST

From: Xiaoyao Li <[email protected]>

Now that everything is there to support 2MB page for TD guest. Because TDX
module TDH.MEM.PAGE.AUG supports 4KB page and 2MB page, set struct
kvm_arch.tdp_max_page_level to 2MB page level.

Signed-off-by: Xiaoyao Li <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/mmu/tdp_mmu.c | 9 ++-------
arch/x86/kvm/vmx/tdx.c | 4 ++--
2 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index fc8f457292b9..7091c45697ef 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -1630,14 +1630,9 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)

sp->nx_huge_page_disallowed = fault->huge_page_disallowed;

- if (is_shadow_present_pte(iter.old_spte)) {
- /*
- * TODO: large page support.
- * Doesn't support large page for TDX now
- */
- KVM_BUG_ON(is_private_sptep(iter.sptep), vcpu->kvm);
+ if (is_shadow_present_pte(iter.old_spte))
r = tdp_mmu_split_huge_page(kvm, &iter, sp, true);
- } else
+ else
r = tdp_mmu_link_sp(kvm, &iter, sp, true);

/*
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 4ed76ef46b0d..3084fa846460 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -487,8 +487,8 @@ int tdx_vm_init(struct kvm *kvm)
*/
kvm_mmu_set_mmio_spte_value(kvm, 0);

- /* TODO: Enable 2mb and 1gb large page support. */
- kvm->arch.tdp_max_page_level = PG_LEVEL_4K;
+ /* TDH.MEM.PAGE.AUG supports up to 2MB page. */
+ kvm->arch.tdp_max_page_level = PG_LEVEL_2M;

/*
* This function initializes only KVM software construct. It doesn't
--
2.25.1