diff mbox series

[RFC,v5,081/104] KVM: VMX: Modify NMI and INTR handlers to take intr_info as function argument

Message ID 961a6534904cc8fd2ddd187ab0a930fbf00cc1ca.1646422845.git.isaku.yamahata@intel.com (mailing list archive)
State New, archived
Headers show
Series KVM TDX basic feature support | expand

Commit Message

Isaku Yamahata March 4, 2022, 7:49 p.m. UTC 
From: Sean Christopherson <sean.j.christopherson@intel.com>

TDX uses different ABI to get information about VM exit.  Pass intr_info to
the NMI and INTR handlers instead of pulling it from vcpu_vmx in
preparation for sharing the bulk of the handlers with TDX.

When the guest TD exits to VMM, RAX holds status and exit reason, RCX holds
exit qualification etc rather than the VMCS fields because VMM doesn't have
access to the VMCS.  The eventual code will be

VMX:
  - get exit reason, intr_info, exit_qualification, and etc from VMCS
  - call NMI/INTR handlers (common code)

TDX:
  - get exit reason, intr_info, exit_qualification, and etc from guest
    registers
  - call NMI/INTR handlers (common code)

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 arch/x86/kvm/vmx/vmx.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

Comments

Paolo Bonzini April 6, 2022, 12:49 p.m. UTC | #1 
On 3/4/22 20:49, isaku.yamahata@intel.com wrote:
> From: Sean Christopherson <sean.j.christopherson@intel.com>
> 
> TDX uses different ABI to get information about VM exit.  Pass intr_info to
> the NMI and INTR handlers instead of pulling it from vcpu_vmx in
> preparation for sharing the bulk of the handlers with TDX.
> 
> When the guest TD exits to VMM, RAX holds status and exit reason, RCX holds
> exit qualification etc rather than the VMCS fields because VMM doesn't have
> access to the VMCS.  The eventual code will be
> 
> VMX:
>    - get exit reason, intr_info, exit_qualification, and etc from VMCS
>    - call NMI/INTR handlers (common code)
> 
> TDX:
>    - get exit reason, intr_info, exit_qualification, and etc from guest
>      registers
>    - call NMI/INTR handlers (common code)
> 
> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> ---
>   arch/x86/kvm/vmx/vmx.c | 17 ++++++++---------
>   1 file changed, 8 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index 4bd1e61b8d45..008400927144 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -6442,28 +6442,27 @@ static void handle_nm_fault_irqoff(struct kvm_vcpu *vcpu)
>   		rdmsrl(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err);
>   }
>   
> -static void handle_exception_nmi_irqoff(struct vcpu_vmx *vmx)
> +static void handle_exception_nmi_irqoff(struct kvm_vcpu *vcpu, u32 intr_info)
>   {
>   	const unsigned long nmi_entry = (unsigned long)asm_exc_nmi_noist;
> -	u32 intr_info = vmx_get_intr_info(&vmx->vcpu);
>   
>   	/* if exit due to PF check for async PF */
>   	if (is_page_fault(intr_info))
> -		vmx->vcpu.arch.apf.host_apf_flags = kvm_read_and_reset_apf_flags();
> +		vcpu->arch.apf.host_apf_flags = kvm_read_and_reset_apf_flags();
>   	/* if exit due to NM, handle before interrupts are enabled */
>   	else if (is_nm_fault(intr_info))
> -		handle_nm_fault_irqoff(&vmx->vcpu);
> +		handle_nm_fault_irqoff(vcpu);
>   	/* Handle machine checks before interrupts are enabled */
>   	else if (is_machine_check(intr_info))
>   		kvm_machine_check();
>   	/* We need to handle NMIs before interrupts are enabled */
>   	else if (is_nmi(intr_info))
> -		handle_interrupt_nmi_irqoff(&vmx->vcpu, nmi_entry);
> +		handle_interrupt_nmi_irqoff(vcpu, nmi_entry);
>   }
>   
> -static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu)
> +static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu,
> +					     u32 intr_info)
>   {
> -	u32 intr_info = vmx_get_intr_info(vcpu);
>   	unsigned int vector = intr_info & INTR_INFO_VECTOR_MASK;
>   	gate_desc *desc = (gate_desc *)host_idt_base + vector;
>   
> @@ -6482,9 +6481,9 @@ void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
>   		return;
>   
>   	if (vmx->exit_reason.basic == EXIT_REASON_EXTERNAL_INTERRUPT)
> -		handle_external_interrupt_irqoff(vcpu);
> +		handle_external_interrupt_irqoff(vcpu, vmx_get_intr_info(vcpu));
>   	else if (vmx->exit_reason.basic == EXIT_REASON_EXCEPTION_NMI)
> -		handle_exception_nmi_irqoff(vmx);
> +		handle_exception_nmi_irqoff(vcpu, vmx_get_intr_info(vcpu));
>   }
>   
>   /*

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
diff mbox series

Patch

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 4bd1e61b8d45..008400927144 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6442,28 +6442,27 @@  static void handle_nm_fault_irqoff(struct kvm_vcpu *vcpu)
 		rdmsrl(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err);
 }
 
-static void handle_exception_nmi_irqoff(struct vcpu_vmx *vmx)
+static void handle_exception_nmi_irqoff(struct kvm_vcpu *vcpu, u32 intr_info)
 {
 	const unsigned long nmi_entry = (unsigned long)asm_exc_nmi_noist;
-	u32 intr_info = vmx_get_intr_info(&vmx->vcpu);
 
 	/* if exit due to PF check for async PF */
 	if (is_page_fault(intr_info))
-		vmx->vcpu.arch.apf.host_apf_flags = kvm_read_and_reset_apf_flags();
+		vcpu->arch.apf.host_apf_flags = kvm_read_and_reset_apf_flags();
 	/* if exit due to NM, handle before interrupts are enabled */
 	else if (is_nm_fault(intr_info))
-		handle_nm_fault_irqoff(&vmx->vcpu);
+		handle_nm_fault_irqoff(vcpu);
 	/* Handle machine checks before interrupts are enabled */
 	else if (is_machine_check(intr_info))
 		kvm_machine_check();
 	/* We need to handle NMIs before interrupts are enabled */
 	else if (is_nmi(intr_info))
-		handle_interrupt_nmi_irqoff(&vmx->vcpu, nmi_entry);
+		handle_interrupt_nmi_irqoff(vcpu, nmi_entry);
 }
 
-static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu)
+static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu,
+					     u32 intr_info)
 {
-	u32 intr_info = vmx_get_intr_info(vcpu);
 	unsigned int vector = intr_info & INTR_INFO_VECTOR_MASK;
 	gate_desc *desc = (gate_desc *)host_idt_base + vector;
 
@@ -6482,9 +6481,9 @@  void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
 		return;
 
 	if (vmx->exit_reason.basic == EXIT_REASON_EXTERNAL_INTERRUPT)
-		handle_external_interrupt_irqoff(vcpu);
+		handle_external_interrupt_irqoff(vcpu, vmx_get_intr_info(vcpu));
 	else if (vmx->exit_reason.basic == EXIT_REASON_EXCEPTION_NMI)
-		handle_exception_nmi_irqoff(vmx);
+		handle_exception_nmi_irqoff(vcpu, vmx_get_intr_info(vcpu));
 }
 
 /*