Re: [Xen-devel] [PATCH v2] docs: add PVH specification

[David Vrabel <david.vrabel@xxxxxxxxxx>]

On 18/09/14 16:57, Jan Beulich wrote:
>>>> On 18.09.14 at 17:27, <roger.pau@xxxxxxxxxx> wrote:
>> +All the segments selectors are set with a flat base at zero.
>> +
>> +The `cs` segment selector attributes are set to 0x0a09b, which describes an
>> +executable and readable code segment only accessible by the most privileged
>> +level. The segment is also set as a 64-bit code segment (`L` flag set) with 
>> a
>> +default operation size of 16bits (`D` flag unset).
> 
> There's no such thing - the L bit set requires the D bit to be clear
> _without_ this meaning a default operation size of 16 bits.
> 
>> +The remaining segment selectors (`ds`, `ss`, `es`, `fs` and `gs`) are all 
>> set
>> +to the same values. The attributes are set to 0x0c093, which implies a read 
>> and
>> +write data segment only accessible by the most privileged level. It is 
>> important
>> +to notice that for the `ss` selector the stack is set to use a 32bit pointer
>> +(`B` flag set).
> 
> The B bit really has no meaning in 64-bit mode, and the stack pointer
> will always be a 64-bit one.

Perhaps this doc should avoid explaining what the bits mean?  The Intel
or AMD reference manuals can be used for this.

David

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