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Subject: Re: [PATCH 3/6] KVM: x86: Add dedicated emulator helper for grabbing
 CPUID.maxphyaddr
To:     Sean Christopherson <sean.j.christopherson@intel.com>
Cc:     Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Jan Kiszka <jan.kiszka@siemens.com>,
        Xiaoyao Li <xiaoyao.li@intel.com>
References: <20200302195736.24777-1-sean.j.christopherson@intel.com>
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 <de2ed4e9-409a-6cb1-e295-ea946be11e82@redhat.com>
 <20200303162808.GJ1439@linux.intel.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <a1b18b18-0bf5-7e7d-ffd9-be1a29609296@redhat.com>
Date:   Tue, 3 Mar 2020 18:21:10 +0100
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On 03/03/20 17:28, Sean Christopherson wrote:
>> I don't think this is a particularly useful change.  Yes, it's not
>> intuitive but is it more than a matter of documentation (and possibly
>> moving the check_cr_write snippet into a separate function)?
> 
> I really don't like duplicating the maxphyaddr logic.  I'm paranoid
> something will come along and change the "effective" maxphyaddr and we'll
> forget all about the emulator, e.g. SEV, TME and paravirt XO all dance
> around maxphyaddr.

Well, I'm paranoid about breaking everything else... :)

Adding a separate emulator_get_maxphyaddr function would at least
simplify grepping, since searching for 0x80000008 isn't exactly intuitive.

Paolo