Re: [PATCH v11 42/45] virt: Add SEV-SNP guest driver

Brijesh Singh
2022-03-04T15:43:52Z

On 3/4/22 9:23 AM, Dave Hansen wrote:
> On 3/4/22 05:17, Brijesh Singh wrote:
>>> BTW, this look like a generic allocator thingy. But it's only ever used
>>> to allocate a 'struct snp_guest_msg'. Why all the trouble to allocate
>>> and free one fixed-size structure? The changelog and comments don't
>>> shed any light.
>> The GHCB specification says that a guest must use shared memory for
>> request, response, and certificate blob. In this patch, you are seeing
>> that {alloc,free}_shared_pages() used only to alloc/free the request and
>> response page. In the last patch, we used the same generic function to
>> allocate the certificate blob with a different size (~16K) than 'struct
>> snp_guest_msg.'
> It sounds like it's worth a sentence or two in the changelog to explain
> this new "allocator" and its future uses.

Will do.