linux-kernel - [PATCH v2 02/14] KVM: x86: Clean up handle_emulation

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Message-Id: <20190827214040.18710-3-sean.j.christopherson@intel.com>
Date:   Tue, 27 Aug 2019 14:40:28 -0700
From:   Sean Christopherson <sean.j.christopherson@...el.com>
To:     Paolo Bonzini <pbonzini@...hat.com>,
        Radim Krčmář <rkrcmar@...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, Liran Alon <liran.alon@...cle.com>
Subject: [PATCH v2 02/14] KVM: x86: Clean up handle_emulation_failure()

When handling emulation failure, return the emulation result directly
instead of capturing it in a local variable.  Future patches will move
additional cases into handle_emulation_failure(), clean up the cruft
before so there isn't an ugly mix of setting a local variable and
returning directly.

Reviewed-by: Vitaly Kuznetsov <vkuznets@...hat.com>
Reviewed-by: Liran Alon <liran.alon@...cle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
---
 arch/x86/kvm/x86.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index cd425f54096a..c6de5bc4fa5e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6207,24 +6207,22 @@ EXPORT_SYMBOL_GPL(kvm_inject_realmode_interrupt);
 
 static int handle_emulation_failure(struct kvm_vcpu *vcpu, int emulation_type)
 {
-	int r = EMULATE_DONE;
-
 	++vcpu->stat.insn_emulation_fail;
 	trace_kvm_emulate_insn_failed(vcpu);
 
 	if (emulation_type & EMULTYPE_NO_UD_ON_FAIL)
 		return EMULATE_FAIL;
 
+	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;
-		r = EMULATE_USER_EXIT;
+		return EMULATE_USER_EXIT;
 	}
 
-	kvm_queue_exception(vcpu, UD_VECTOR);
-
-	return r;
+	return EMULATE_DONE;
 }
 
 static bool reexecute_instruction(struct kvm_vcpu *vcpu, gva_t cr2,
-- 
2.22.0