From a7d5c7ce41ac1e2537d78ddb57ef0ac4f737aa19 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 22 Sep 2020 07:43:14 -0400 Subject: [PATCH] KVM: nSVM: delay MSR permission processing to first nested VM run Allow userspace to set up the memory map after KVM_SET_NESTED_STATE; to do so, move the call to nested_svm_vmrun_msrpm inside the KVM_REQ_GET_NESTED_STATE_PAGES handler (which is currently not used by nSVM). This is similar to what VMX does already. Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm/nested.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index da5e87d..ba50ff6 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -196,6 +196,20 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) return true; } +static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu) +{ + struct vcpu_svm *svm = to_svm(vcpu); + if (!nested_svm_vmrun_msrpm(svm)) { + vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + vcpu->run->internal.suberror = + KVM_INTERNAL_ERROR_EMULATION; + vcpu->run->internal.ndata = 0; + return false; + } + + return true; +} + static bool nested_vmcb_check_controls(struct vmcb_control_area *control) { if ((vmcb_is_intercept(control, INTERCEPT_VMRUN)) == 0) @@ -698,6 +712,8 @@ void svm_leave_nested(struct vcpu_svm *svm) copy_vmcb_control_area(&vmcb->control, &hsave->control); nested_svm_uninit_mmu_context(&svm->vcpu); } + + kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, &svm->vcpu); } static int nested_svm_exit_handled_msr(struct vcpu_svm *svm) @@ -1142,9 +1158,7 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu, load_nested_vmcb_control(svm, ctl); nested_prepare_vmcb_control(svm); - if (!nested_svm_vmrun_msrpm(svm)) - goto out_free; - + kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu); ret = 0; out_free: kfree(save); @@ -1155,6 +1169,7 @@ out_free: struct kvm_x86_nested_ops svm_nested_ops = { .check_events = svm_check_nested_events, + .get_nested_state_pages = svm_get_nested_state_pages, .get_state = svm_get_nested_state, .set_state = svm_set_nested_state, }; -- 2.7.4