Re: [Xen-devel] [PATCH v14 3/3] iommu: add rmrr Xen command line option for extra rmrrs

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 24.01.17 at 16:58, <venu.busireddy@xxxxxxxxxx> wrote:
> On Tue, Jan 24, 2017 at 08:52:50AM -0700, Jan Beulich wrote:
>> >>> On 24.01.17 at 16:35, <venu.busireddy@xxxxxxxxxx> wrote:
>> > On Tue, Jan 24, 2017 at 01:46:44AM -0700, Jan Beulich wrote:
>> >> >>> On 23.01.17 at 19:20, <venu.busireddy@xxxxxxxxxx> wrote:
>> >> > +        overlap = false;
>> >> > +        list_for_each_entry(rmrru, &acpi_rmrr_units, list)
>> >> > +        {
>> >> > +            if ( pfn_to_paddr(base) <= rmrru->end_address &&
>> >> > +                 rmrru->base_address <= pfn_to_paddr(end) )
>> >> 
>> >> So this now looks correct as long as rmrru->base_address is
>> >> page aligned (as required by the spec), which should be good
>> >> enough for now (considering that we make this assumption
>> >> elsewhere). Nevertheless it would have been nice if you had,
>> >> following the subsequent discussion with Elena, accounted for
>> >> spec violations here.
>> >> 
>> >> > +        rmrr->segment = seg;
>> >> > +        rmrr->base_address = pfn_to_paddr(user_rmrrs[i].base_pfn);
>> >> > +        /* Align the end_address to the end of the page */
>> >> > +        rmrr->end_address = pfn_to_paddr(user_rmrrs[i].end_pfn) | 
>> > ~PAGE_MASK_4K;
>> >> 
>> >> Hmm, Ive just checked - in my reply to Elena I had intentionally used
>> >> PAGE_MASK here (and I recall correcting it from PAGE_MASK_4K).
>> >> What has led you to use PAGE_MASK_4K here, when pfn_to_paddr()
>> >> uses PAGE_SHIFT?
>> > 
>> > Elena suggested to use PAGE_MASK_4K because the functions in
>> > drivers/passthrough/vtd/iommu.c (including rmrr_identity_mapping())
>> > use the _4K. With the current assumptions, both will work.
>> 
>> Granted this is somewhat of a mess, but I'd prefer if at least within
>> a single statement things would be consistent in which page size is
>> being meant.
>> 
>> > If you would like me to change this to PAGE_MASK, I will do so before
>> > committing. Please let me know.
>> 
>> As said, I don't see a need for you to re-submit, unless there are
>> other issues in need of taking care of.
> 
> Sure. I will change it to PAGE_MASK, but I will not resubmit the
> patches. I will change it and commit it. Of course, assuming that there
> are no other changes suggested by others.

I don't follow this repeated mentioning of "commit" by you. I don't
think you can commit to our staging tree. And actually committing
the series depends on - as also stated before - Kevin confirming
his acks, which you had wrongly left in place.

> Do I understand that I have your Ack?

Well, I had given you my (conditional) R-b in the (my) morning.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel