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-rw-r--r--arch/x86/kvm/mmu.c16
1 files changed, 10 insertions, 6 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 1e9ba81accba..d3c3d5e5ffd4 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -5602,14 +5602,18 @@ static int alloc_mmu_pages(struct kvm_vcpu *vcpu)
struct page *page;
int i;
- if (tdp_enabled)
- return 0;
-
/*
- * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
- * Therefore we need to allocate shadow page tables in the first
- * 4GB of memory, which happens to fit the DMA32 zone.
+ * When using PAE paging, the four PDPTEs are treated as 'root' pages,
+ * while the PDP table is a per-vCPU construct that's allocated at MMU
+ * creation. When emulating 32-bit mode, cr3 is only 32 bits even on
+ * x86_64. Therefore we need to allocate the PDP table in the first
+ * 4GB of memory, which happens to fit the DMA32 zone. Except for
+ * SVM's 32-bit NPT support, TDP paging doesn't use PAE paging and can
+ * skip allocating the PDP table.
*/
+ if (tdp_enabled && kvm_x86_ops->get_tdp_level(vcpu) > PT32E_ROOT_LEVEL)
+ return 0;
+
page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_DMA32);
if (!page)
return -ENOMEM;