Re: [PATCH v5 05/10] x86emul: support MOVDIR64B insn

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

On 03/04/2020 08:57, Jan Beulich wrote:
> On 03.04.2020 01:12, Andrew Cooper wrote:
>> On 24/03/2020 12:34, Jan Beulich wrote:
>>> Introduce a new blk() hook, paralleling the rmw() on in certain way, but
>>> being intended for larger data sizes, and hence its HVM intermediate
>>> handling function doesn't fall back to splitting the operation if the
>>> requested virtual address can't be mapped.
>>>
>>> Note that SDM revision 071 doesn't specify exception behavior for
>>> ModRM.mod == 0b11; assuming #UD here.
>>>
>>> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
>> Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> Thanks much, but I'm puzzled by you providing this, and hence
> would like to double check: You specifically asked that I take
> care of the cachability issue for MOVDIRI before you would ack
> that change. How come you're not similarly concerned here?

This executes the MOVDIR64B instruction directly, so those properties
are taken care of.  (I think?)

The MOVDIRI support just does a memcpy().

~Andrew