[PATCH v8 14/14] KVM: TDX: Allow 2MB large page for TD GUEST

From: isaku . yamahata
Date: Mon Feb 26 2024 - 04:15:08 EST


From: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>

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 <xiaoyao.li@xxxxxxxxx>
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
arch/x86/kvm/mmu/tdp_mmu.c | 9 ++-------
arch/x86/kvm/vmx/tdx.c | 7 +++++--
2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index d6ce8496803f..8663e163427c 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -1544,14 +1544,9 @@ 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 5b4d94a6c6e2..1a94b1072068 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -3109,8 +3109,11 @@ int tdx_gmem_max_level(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn,
if (!is_private)
return 0;

- /* TODO: Enable 2mb and 1gb large page support. */
- *max_level = min(*max_level, PG_LEVEL_4K);
+ /*
+ * TDH.MEM.PAGE.AUG supports up to 2MB page.
+ * TODO: Enable 1gb large page support.
+ */
+ *max_level = min(*max_level, PG_LEVEL_2M);
return 0;
}

--
2.25.1