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Date:   Fri, 15 Nov 2019 10:01:22 -0800
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Jim Mattson <jmattson@google.com>, kvm list <kvm@vger.kernel.org>
Subject: Re: KVM_GET_SUPPORTED_CPUID
Message-ID: <20191115180122.GB6055@linux.intel.com>
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On Fri, Nov 15, 2019 at 12:42:17PM +0100, Paolo Bonzini wrote:
> On 14/11/19 21:09, Jim Mattson wrote:
> > If I see "AuthenticAMD" in EBX/EDX/ECX,
> > does that mean that "GenuineIntel" is *not* supported? I thought
> > people were having reasonable success with cross-vendor migration.
> 
> This is (2).  But in general passing the host value is the safe choice,
> everything else has reasonable success but it's not something I would
> recommend in production (and it's something I wouldn't mind removing,
> really).

Maybe keep it but add a pr_warn_once() to inform the user that exposions
are likely?  Or make it opt-in via a module param?  I've found this useful
for smoke testing patches that touch AMD/Hygon/Zhaoxin/Centaur code.