From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: rdmsr_safe in Linux PV (under Xen) gets an #GP:Re: [Fedora-xen]
 Running fedora xen on top of KVM?
Date: Fri, 18 Sep 2015 17:27:55 +0200
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To: Borislav Petkov <bp@alien8.de>, Andy Lutomirski <luto@amacapital.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>, Cole Robinson <crobinso@redhat.com>, Xen Devel <xen-devel@lists.xensource.com>, kvm list <kvm@vger.kernel.org>, M A Young <m.a.young@durham.ac.uk>, xen <xen@lists.fedoraproject.org>
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On 18/09/2015 15:54, Borislav Petkov wrote:
> On Thu, Sep 17, 2015 at 01:23:31PM -0700, Andy Lutomirski wrote:
>> > Cc: Borislav.  Is TSEG guaranteed to exist?  Can we defer that until
> Why not? It is the tseg base address.
> 
> I think this is kvm injecting a #GP as it is not ignoring this MSR.
> Presumably modprobing kvm with "ignore_msrs=1" or so should hide the
> issue IIUC...

We should return 0 for the tseg MSRs.  KVM always handles them in the
northbridge emulation code, like Intel chipsets do.  Will send a patch.

Paolo