Re: [PATCH 04/12] swiotlb-xen: ensure to issue well-formed XENMEM_exchange requests

From: Jan Beulich
Date: Mon Sep 13 2021 - 03:18:55 EST


On 11.09.2021 01:14, Stefano Stabellini wrote:
> On Tue, 7 Sep 2021, Jan Beulich wrote:
>> While the hypervisor hasn't been enforcing this, we would still better
>> avoid issuing requests with GFNs not aligned to the requested order.
>>
>> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
>> ---
>> I wonder how useful it is to include the alignment in the panic()
>> message.
>
> Not very useful given that it is static. I don't mind either way but you
> can go ahead and remove it if you prefer (and it would make the line
> shorter.)
>
>
>> I further wonder how useful it is to wrap "bytes" in
>> PAGE_ALIGN(), when it is a multiple of a segment's size anyway (or at
>> least was supposed to be, prior to "swiotlb-xen: maintain slab count
>> properly").
>
> This one I would keep, to make sure to print out the same amount passed
> to memblock_alloc.

Oh - if I was to drop it from the printk(), I would have been meaning to
also drop it there. If it's useless, then it's useless everywhere.

Jan