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Subject: Re: [PATCH v1 1/8] virtio: Force only split mode with protected guest
To:     Andi Kleen <ak@linux.intel.com>, mst@redhat.com
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From:   Jason Wang <jasowang@redhat.com>
Message-ID: <93f58cfd-be59-1ea6-e0d0-6840c14d6980@redhat.com>
Date:   Fri, 4 Jun 2021 10:29:47 +0800
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在 2021/6/3 下午9:55, Andi Kleen 写道:
>
>> Ok, but what I meant is this, if we don't read from the descriptor 
>> ring, and validate all the other metadata supplied by the device 
>> (used id and len). Then there should be no way for the device to 
>> suppress the dma flags to write to the indirect descriptor table.
>>
>> Or do you have an example how it can do that?
>
> I don't. If you can validate everything it's probably ok
>
> The only drawback is even more code to audit and test.
>
> -Andi
>
>

Ok, then I'm going to post a formal series, please have a look and we 
can start from there.

Thanks