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From:   Alexander Graf <graf@amazon.com>
To:     kvm list <kvm@vger.kernel.org>
CC:     Aaron Lewis <aaronlewis@google.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        "Joerg Roedel" <joro@8bytes.org>,
        KarimAllah Raslan <karahmed@amazon.de>,
        "Dan Carpenter" <dan.carpenter@oracle.com>,
        Maxim Levitsky <mlevitsk@redhat.com>,
        <linux-doc@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH v8 1/8] KVM: x86: Return -ENOENT on unimplemented MSRs
Date:   Fri, 25 Sep 2020 16:34:15 +0200
Message-ID: <20200925143422.21718-2-graf@amazon.com>
In-Reply-To: <20200925143422.21718-1-graf@amazon.com>
References: <20200925143422.21718-1-graf@amazon.com>
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When we find an MSR that we can not handle, bubble up that error code as
MSR error return code. Follow up patches will use that to expose the fact
that an MSR is not handled by KVM to user space.

Suggested-by: Aaron Lewis <aaronlewis@google.com>
Signed-off-by: Alexander Graf <graf@amazon.com>
---
 arch/x86/kvm/x86.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 17f4995e80a7..58d513c5e264 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -267,7 +267,7 @@ static int kvm_msr_ignored_check(struct kvm_vcpu *vcpu, u32 msr,
 	} else {
 		vcpu_debug_ratelimited(vcpu, "unhandled %s: 0x%x data 0x%llx\n",
 				       op, msr, data);
-		return 1;
+		return -ENOENT;
 	}
 }
 
-- 
2.28.0.394.ge197136389


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