Re: [PATCH v4 0/7] Use 1st-level for IOVA translation

[Lu Baolu]

Hi again,

On 2019/12/20 19:50, Liu, Yi L wrote:
> 3) Per VT-d spec, FLPT has canonical requirement to the input
> addresses. So I'd suggest to add some enhance regards to it.
> Please refer to chapter 3.6:-).
>
> 3.6 First-Level Translation
> First-level translation restricts the input-address to a canonical address (i.e., address bits 63:N have
> the same value as address bit [N-1], where N is 48-bits with 4-level paging and 57-bits with 5-level
> paging). Requests subject to first-level translation by remapping hardware are subject to canonical
> address checking as a pre-condition for first-level translation, and a violation is treated as a
> translation-fault.

It seems to be a conflict at bit 63. It should be the same as bit[N-1]
according to the canonical address requirement; but it is also used as
the XD control. Any thought?

Best regards,
baolu