From d51e1d3f6b4236e0352407d8a63f5c5f71ce193d Mon Sep 17 00:00:00 2001 From: Maxim Levitsky Date: Thu, 14 Jan 2021 22:54:47 +0200 Subject: [PATCH] KVM: nVMX: Sync unsync'd vmcs02 state to vmcs12 on migration Even when we are outside the nested guest, some vmcs02 fields may not be in sync vs vmcs12. This is intentional, even across nested VM-exit, because the sync can be delayed until the nested hypervisor performs a VMCLEAR or a VMREAD/VMWRITE that affects those rarely accessed fields. However, during KVM_GET_NESTED_STATE, the vmcs12 has to be up to date to be able to restore it. To fix that, call copy_vmcs02_to_vmcs12_rare() before the vmcs12 contents are copied to userspace. Fixes: 7952d769c29ca ("KVM: nVMX: Sync rarely accessed guest fields only when needed") Reviewed-by: Sean Christopherson Signed-off-by: Maxim Levitsky Message-Id: <20210114205449.8715-2-mlevitsk@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/nested.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 0fbb46990dfc..776688f9d101 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -6077,11 +6077,14 @@ static int vmx_get_nested_state(struct kvm_vcpu *vcpu, if (is_guest_mode(vcpu)) { sync_vmcs02_to_vmcs12(vcpu, vmcs12); sync_vmcs02_to_vmcs12_rare(vcpu, vmcs12); - } else if (!vmx->nested.need_vmcs12_to_shadow_sync) { - if (vmx->nested.hv_evmcs) - copy_enlightened_to_vmcs12(vmx); - else if (enable_shadow_vmcs) - copy_shadow_to_vmcs12(vmx); + } else { + copy_vmcs02_to_vmcs12_rare(vcpu, get_vmcs12(vcpu)); + if (!vmx->nested.need_vmcs12_to_shadow_sync) { + if (vmx->nested.hv_evmcs) + copy_enlightened_to_vmcs12(vmx); + else if (enable_shadow_vmcs) + copy_shadow_to_vmcs12(vmx); + } } BUILD_BUG_ON(sizeof(user_vmx_nested_state->vmcs12) < VMCS12_SIZE); -- 2.34.1