From:   isaku.yamahata@intel.com
To:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     isaku.yamahata@intel.com, isaku.yamahata@gmail.com,
        Paolo Bonzini <pbonzini@redhat.com>, erdemaktas@google.com,
        Sean Christopherson <seanjc@google.com>,
        Sagi Shahar <sagis@google.com>,
        David Matlack <dmatlack@google.com>,
        Kai Huang <kai.huang@intel.com>,
        Zhi Wang <zhi.wang.linux@gmail.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>
Subject: [PATCH v13 080/113] KVM: VMX: Modify NMI and INTR handlers to take intr_info as function argument
Date:   Sun, 12 Mar 2023 10:56:44 -0700
Message-Id: <b4f836d8e3e347b35a1e0f52df9a750c522ae6c5.1678643052.git.isaku.yamahata@intel.com>
In-Reply-To: <cover.1678643051.git.isaku.yamahata@intel.com>
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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 | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index ebf262496f47..bbf286a5c338 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6868,24 +6868,22 @@ 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_irqoff(struct vcpu_vmx *vmx)
+static void handle_exception_irqoff(struct kvm_vcpu *vcpu, u32 intr_info)
 {
-	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();
 }
 
-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;
 
@@ -6908,9 +6906,9 @@ 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_irqoff(vmx);
+		handle_exception_irqoff(vcpu, vmx_get_intr_info(vcpu));
 }
 
 /*
-- 
2.25.1