linux-kernel - [PATCH v2 11/13] KVM: x86: Add helper to "handle" internal emulation error

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Date:   Tue, 18 Feb 2020 15:29:51 -0800
From:   Sean Christopherson <sean.j.christopherson@...el.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <sean.j.christopherson@...el.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH v2 11/13] KVM: x86: Add helper to "handle" internal emulation error

Add a helper to set the appropriate error codes in vcpu->run when
emulation fails (future patches will add additional failure scenarios).

Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
---
 arch/x86/kvm/x86.c | 32 ++++++++++++++------------------
 1 file changed, 14 insertions(+), 18 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e1eaca65756b..7bffdc6f9e1b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6491,6 +6491,14 @@ void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip)
 }
 EXPORT_SYMBOL_GPL(kvm_inject_realmode_interrupt);
 
+static int internal_emulation_error(struct kvm_vcpu *vcpu)
+{
+	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+	vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
+	vcpu->run->internal.ndata = 0;
+	return 0;
+}
+
 static int handle_emulation_failure(struct x86_emulate_ctxt *ctxt,
 				    int emulation_type)
 {
@@ -6504,21 +6512,13 @@ static int handle_emulation_failure(struct x86_emulate_ctxt *ctxt,
 		return 1;
 	}
 
-	if (emulation_type & EMULTYPE_SKIP) {
-		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
-		vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
-		vcpu->run->internal.ndata = 0;
-		return 0;
-	}
+	if (emulation_type & EMULTYPE_SKIP)
+		return internal_emulation_error(vcpu);
 
 	kvm_queue_exception(vcpu, UD_VECTOR);
 
-	if (!is_guest_mode(vcpu) && kvm_x86_ops->get_cpl(vcpu) == 0) {
-		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
-		vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
-		vcpu->run->internal.ndata = 0;
-		return 0;
-	}
+	if (!is_guest_mode(vcpu) && kvm_x86_ops->get_cpl(vcpu) == 0)
+		return internal_emulation_error(vcpu);
 
 	return 1;
 }
@@ -8986,12 +8986,8 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int idt_index,
 
 	ret = emulator_task_switch(ctxt, tss_selector, idt_index, reason,
 				   has_error_code, error_code);
-	if (ret) {
-		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
-		vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
-		vcpu->run->internal.ndata = 0;
-		return 0;
-	}
+	if (ret)
+		return internal_emulation_error(vcpu);
 
 	kvm_rip_write(vcpu, ctxt->eip);
 	kvm_set_rflags(vcpu, ctxt->eflags);
-- 
2.24.1