linux-kernel - [PATCH v2 7/9] KVM: SVM: split svm_handle_invalid

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Message-Id: <20210401135451.1004564-8-mlevitsk@redhat.com>
Date:   Thu,  1 Apr 2021 16:54:49 +0300
From:   Maxim Levitsky <mlevitsk@...hat.com>
To:     kvm@...r.kernel.org
Cc:     x86@...nel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)),
        Ingo Molnar <mingo@...hat.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Sean Christopherson <seanjc@...gle.com>,
        Marc Zyngier <maz@...nel.org>,
        Catalin Marinas <catalin.marinas@....com>,
        linux-kernel@...r.kernel.org (open list),
        Julien Thierry <julien.thierry.kdev@...il.com>,
        Stefano Garzarella <sgarzare@...hat.com>,
        Borislav Petkov <bp@...en8.de>,
        Suzuki K Poulose <suzuki.poulose@....com>,
        Jonathan Corbet <corbet@....net>, Jessica Yu <jeyu@...nel.org>,
        "H. Peter Anvin" <hpa@...or.com>,
        Jan Kiszka <jan.kiszka@...mens.com>,
        Will Deacon <will@...nel.org>,
        kvmarm@...ts.cs.columbia.edu (open list:KERNEL VIRTUAL MACHINE FOR
        ARM64 (KVM/arm64)), Paolo Bonzini <pbonzini@...hat.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Vasily Gorbik <gor@...ux.ibm.com>,
        Joerg Roedel <joro@...tes.org>,
        Claudio Imbrenda <imbrenda@...ux.ibm.com>,
        Jim Mattson <jmattson@...gle.com>,
        Cornelia Huck <cohuck@...hat.com>,
        David Hildenbrand <david@...hat.com>,
        Maxim Levitsky <mlevitsk@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Janosch Frank <frankja@...ux.ibm.com>,
        Christian Borntraeger <borntraeger@...ibm.com>,
        linux-s390@...r.kernel.org (open list:S390),
        Heiko Carstens <hca@...ux.ibm.com>,
        Kieran Bingham <kbingham@...nel.org>,
        linux-doc@...r.kernel.org (open list:DOCUMENTATION),
        linux-arm-kernel@...ts.infradead.org (moderated list:KERNEL VIRTUAL
        MACHINE FOR ARM64 (KVM/arm64)), James Morse <james.morse@....com>
Subject: [PATCH v2 7/9] KVM: SVM: split svm_handle_invalid_exit

Split the check for having a vmexit handler to
svm_check_exit_valid, and make svm_handle_invalid_exit
only handle a vmexit that is already not valid.

Signed-off-by: Maxim Levitsky <mlevitsk@...hat.com>
---
 arch/x86/kvm/svm/svm.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 271196400495..2aa951bc470c 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3220,12 +3220,14 @@ static void dump_vmcb(struct kvm_vcpu *vcpu)
 	       "excp_to:", save->last_excp_to);
 }
 
-static int svm_handle_invalid_exit(struct kvm_vcpu *vcpu, u64 exit_code)
+static bool svm_check_exit_valid(struct kvm_vcpu *vcpu, u64 exit_code)
 {
-	if (exit_code < ARRAY_SIZE(svm_exit_handlers) &&
-	    svm_exit_handlers[exit_code])
-		return 0;
+	return (exit_code < ARRAY_SIZE(svm_exit_handlers) &&
+		svm_exit_handlers[exit_code]);
+}
 
+static int svm_handle_invalid_exit(struct kvm_vcpu *vcpu, u64 exit_code)
+{
 	vcpu_unimpl(vcpu, "svm: unexpected exit reason 0x%llx\n", exit_code);
 	dump_vmcb(vcpu);
 	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
@@ -3233,14 +3235,13 @@ static int svm_handle_invalid_exit(struct kvm_vcpu *vcpu, u64 exit_code)
 	vcpu->run->internal.ndata = 2;
 	vcpu->run->internal.data[0] = exit_code;
 	vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu;
-
-	return -EINVAL;
+	return 0;
 }
 
 int svm_invoke_exit_handler(struct kvm_vcpu *vcpu, u64 exit_code)
 {
-	if (svm_handle_invalid_exit(vcpu, exit_code))
-		return 0;
+	if (!svm_check_exit_valid(vcpu, exit_code))
+		return svm_handle_invalid_exit(vcpu, exit_code);
 
 #ifdef CONFIG_RETPOLINE
 	if (exit_code == SVM_EXIT_MSR)
-- 
2.26.2