From 1fb883bb827ee8efc1cc9ea0154f953f8a219d38 Mon Sep 17 00:00:00 2001 From: Ladi Prosek Date: Tue, 4 Apr 2017 14:18:53 +0200 Subject: [PATCH] KVM: nVMX: initialize PML fields in vmcs02 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit L2 was running with uninitialized PML fields which led to incomplete dirty bitmap logging. This manifested as all kinds of subtle erratic behavior of the nested guest. Fixes: 843e4330573c ("KVM: VMX: Add PML support in VMX") Signed-off-by: Ladi Prosek Signed-off-by: Radim Krčmář --- arch/x86/kvm/vmx.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 605183291069..259e9b28ccf8 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -10270,6 +10270,18 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, } + if (enable_pml) { + /* + * Conceptually we want to copy the PML address and index from + * vmcs01 here, and then back to vmcs01 on nested vmexit. But, + * since we always flush the log on each vmexit, this happens + * to be equivalent to simply resetting the fields in vmcs02. + */ + ASSERT(vmx->pml_pg); + vmcs_write64(PML_ADDRESS, page_to_phys(vmx->pml_pg)); + vmcs_write16(GUEST_PML_INDEX, PML_ENTITY_NUM - 1); + } + if (nested_cpu_has_ept(vmcs12)) { kvm_mmu_unload(vcpu); nested_ept_init_mmu_context(vcpu);