[PATCH 1/6] KVM: nVMX: delay loading of PDPTRs to KVM_REQ_GET_NESTED_STATE_PAGES

From: Maxim Levitsky
Date: Thu Apr 01 2021 - 14:44:51 EST


Similar to the rest of guest page accesses after migration,
this should be delayed to KVM_REQ_GET_NESTED_STATE_PAGES
request.

Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
---
arch/x86/kvm/vmx/nested.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index fd334e4aa6db..b44f1f6b68db 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2564,11 +2564,6 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
return -EINVAL;
}

- /* Shadow page tables on either EPT or shadow page tables. */
- if (nested_vmx_load_cr3(vcpu, vmcs12->guest_cr3, nested_cpu_has_ept(vmcs12),
- entry_failure_code))
- return -EINVAL;
-
/*
* Immediately write vmcs02.GUEST_CR3. It will be propagated to vmcs12
* on nested VM-Exit, which can occur without actually running L2 and
@@ -3109,11 +3104,16 @@ static bool nested_get_evmcs_page(struct kvm_vcpu *vcpu)
static bool nested_get_vmcs12_pages(struct kvm_vcpu *vcpu)
{
struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+ enum vm_entry_failure_code entry_failure_code;
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct kvm_host_map *map;
struct page *page;
u64 hpa;

+ if (nested_vmx_load_cr3(vcpu, vmcs12->guest_cr3, nested_cpu_has_ept(vmcs12),
+ &entry_failure_code))
+ return false;
+
if (nested_cpu_has2(vmcs12, SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)) {
/*
* Translate L1 physical address to host physical
@@ -3357,6 +3357,10 @@ enum nvmx_vmentry_status nested_vmx_enter_non_root_mode(struct kvm_vcpu *vcpu,
}

if (from_vmentry) {
+ if (nested_vmx_load_cr3(vcpu, vmcs12->guest_cr3,
+ nested_cpu_has_ept(vmcs12), &entry_failure_code))
+ goto vmentry_fail_vmexit_guest_mode;
+
failed_index = nested_vmx_load_msr(vcpu,
vmcs12->vm_entry_msr_load_addr,
vmcs12->vm_entry_msr_load_count);
--
2.26.2