From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: nVMX MSR load/store feature
Date: Mon, 15 Dec 2014 13:10:44 +0100
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To: Eugene Korenevsky <ekorenevsky@gmail.com>,
	Jan Kiszka <jan.kiszka@web.de>, Bandan Das <bsd@redhat.com>,
	kvm@vger.kernel.org,
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	<rkrcmar@redhat.com>, Wanpeng Li <wanpeng.li@linux.intel.com>
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On 14/12/2014 02:17, Eugene Korenevsky wrote:
> Hi there,
> 
> Please DO NOT take v3 version of patchset in account. It contains bug
> (missing check for MSR load/store area size in
> `nested_vmx_check_msr_switch`). This bug has been fixed in v4 version
> of patchset.

The diff is just

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index d6fe958a0403..09ccf6c09435 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -8305,6 +8305,8 @@ static int nested_vmx_check_msr_switch(struct kvm_vcpu *vcpu,
 		WARN_ON(1);
 		return -EINVAL;
 	}
+	if (count == 0)
+		return 0;
 	if (!IS_ALIGNED(addr, 16) || addr >> maxphyaddr ||
 	    (addr + count * sizeof(struct vmx_msr_entry) - 1) >> maxphyaddr) {
 		pr_warn_ratelimited(

right?

Paolo