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Subject: Re: [PATCH v2 00/12] KVM/X86: Introduce a new guest mapping interface
To:     "Raslan, KarimAllah" <karahmed@amazon.de>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "rkrcmar@redhat.com" <rkrcmar@redhat.com>,
        "david@redhat.com" <david@redhat.com>
References: <1523829198-13236-1-git-send-email-karahmed@amazon.de>
 <b390f953-6fe3-1119-15eb-e3b31e609305@redhat.com>
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From:   Paolo Bonzini <pbonzini@redhat.com>
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Message-ID: <15b8718d-f209-1a3c-349e-497ae5f0d191@redhat.com>
Date:   Wed, 11 Jul 2018 12:26:23 +0200
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On 10/07/2018 14:06, Raslan, KarimAllah wrote:
> On Mon, 2018-04-16 at 13:10 +0200, Paolo Bonzini wrote:
>> On 15/04/2018 23:53, KarimAllah Ahmed wrote:
>>>
>>> Guest memory can either be directly managed by the kernel (i.e. have a "struct
>>> page") or they can simply live outside kernel control (i.e. do not have a
>>> "struct page"). KVM mostly support these two modes, except in a few places
>>> where the code seems to assume that guest memory must have a "struct page".
>>>
>>> This patchset introduces a new mapping interface to map guest memory into host
>>> kernel memory which also supports PFN-based memory (i.e. memory without 'struct
>>> page'). It also converts all offending code to this interface or simply
>>> read/write directly from guest memory.
>>>
>>> As far as I can see all offending code is now fixed except the APIC-access page
>>> which I will handle in a seperate patch.
>>
>> I assume the caching will also be a separate patch.
>>
>> It looks good except that I'd squash patches 4 and 9 together.  But I'd
>> like a second set of eyes to look at it.
> 
> BTW, Why did you want to squash these 2 patches specifically? They are 
> very unrelated to me. The only common thing is that they switch from 
> code that supports only "struct page" to code that supports PFN only
> but this is also common for all other patches.

Probably at the time I was thinking they both affect cmpxchg, but really
they are gpte and emulator respectively.  Looks like I have 12 more
patches on my review queue then! *ouch*

Paolo

>>
>> Thanks,
>>
>> Paolo
>>
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