[PATCH v7 080/102] KVM: VMX: Modify NMI and INTR handlers to take intr_info as function argument

isaku.yamahata
2022-06-27T22:00:36Z

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>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.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 3aca3976ba1b..ccc245fbe0a1 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6677,28 +6677,27 @@ 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;

@@ -6718,9 +6717,9 @@ 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));
}

/*
--
2.25.1