From 96b100cd1464ce41d5d6b083b1fe5ceace8eef8a Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 17 Mar 2020 18:32:50 +0100 Subject: KVM: nVMX: remove side effects from nested_vmx_exit_reflected The name of nested_vmx_exit_reflected suggests that it's purely a test, but it actually marks VMCS12 pages as dirty. Move this to vmx_handle_exit, observing that the initial nested_run_pending check in nested_vmx_exit_reflected is pointless---nested_run_pending has just been cleared in vmx_vcpu_run and won't be set until handle_vmlaunch or handle_vmresume. Suggested-by: Vitaly Kuznetsov Reviewed-by: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/nested.c | 18 ++---------------- arch/x86/kvm/vmx/nested.h | 1 + arch/x86/kvm/vmx/vmx.c | 19 +++++++++++++++++-- 3 files changed, 20 insertions(+), 18 deletions(-) (limited to 'arch/x86/kvm') diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 8578513907d7..4ff859c99946 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -3527,7 +3527,7 @@ static void vmcs12_save_pending_event(struct kvm_vcpu *vcpu, } -static void nested_mark_vmcs12_pages_dirty(struct kvm_vcpu *vcpu) +void nested_mark_vmcs12_pages_dirty(struct kvm_vcpu *vcpu) { struct vmcs12 *vmcs12 = get_vmcs12(vcpu); gfn_t gfn; @@ -5543,8 +5543,7 @@ bool nested_vmx_exit_reflected(struct kvm_vcpu *vcpu, u32 exit_reason) struct vcpu_vmx *vmx = to_vmx(vcpu); struct vmcs12 *vmcs12 = get_vmcs12(vcpu); - if (vmx->nested.nested_run_pending) - return false; + WARN_ON_ONCE(vmx->nested.nested_run_pending); if (unlikely(vmx->fail)) { trace_kvm_nested_vmenter_failed( @@ -5553,19 +5552,6 @@ bool nested_vmx_exit_reflected(struct kvm_vcpu *vcpu, u32 exit_reason) return true; } - /* - * The host physical addresses of some pages of guest memory - * are loaded into the vmcs02 (e.g. vmcs12's Virtual APIC - * Page). The CPU may write to these pages via their host - * physical address while L2 is running, bypassing any - * address-translation-based dirty tracking (e.g. EPT write - * protection). - * - * Mark them dirty on every exit from L2 to prevent them from - * getting out of sync with dirty tracking. - */ - nested_mark_vmcs12_pages_dirty(vcpu); - trace_kvm_nested_vmexit(kvm_rip_read(vcpu), exit_reason, vmcs_readl(EXIT_QUALIFICATION), vmx->idt_vectoring_info, diff --git a/arch/x86/kvm/vmx/nested.h b/arch/x86/kvm/vmx/nested.h index 21d36652f213..f70968b76d33 100644 --- a/arch/x86/kvm/vmx/nested.h +++ b/arch/x86/kvm/vmx/nested.h @@ -33,6 +33,7 @@ int vmx_get_vmx_msr(struct nested_vmx_msrs *msrs, u32 msr_index, u64 *pdata); int get_vmx_mem_address(struct kvm_vcpu *vcpu, unsigned long exit_qualification, u32 vmx_instruction_info, bool wr, int len, gva_t *ret); void nested_vmx_pmu_entry_exit_ctls_update(struct kvm_vcpu *vcpu); +void nested_mark_vmcs12_pages_dirty(struct kvm_vcpu *vcpu); bool nested_vmx_check_io_bitmaps(struct kvm_vcpu *vcpu, unsigned int port, int size); diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index b447d66f44e6..07299a957d4a 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -5851,8 +5851,23 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, if (vmx->emulation_required) return handle_invalid_guest_state(vcpu); - if (is_guest_mode(vcpu) && nested_vmx_exit_reflected(vcpu, exit_reason)) - return nested_vmx_reflect_vmexit(vcpu, exit_reason); + if (is_guest_mode(vcpu)) { + /* + * The host physical addresses of some pages of guest memory + * are loaded into the vmcs02 (e.g. vmcs12's Virtual APIC + * Page). The CPU may write to these pages via their host + * physical address while L2 is running, bypassing any + * address-translation-based dirty tracking (e.g. EPT write + * protection). + * + * Mark them dirty on every exit from L2 to prevent them from + * getting out of sync with dirty tracking. + */ + nested_mark_vmcs12_pages_dirty(vcpu); + + if (nested_vmx_exit_reflected(vcpu, exit_reason)) + return nested_vmx_reflect_vmexit(vcpu, exit_reason); + } if (exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY) { dump_vmcs(); -- cgit v1.2.3