Re: [Xen-devel] [PATCH v6 09/14] mm / iommu: include need_iommu() test in iommu_use_hap_pt()

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 11.09.18 at 11:39, <Paul.Durrant@xxxxxxxxxx> wrote:
>>  -----Original Message-----
>> From: Jan Beulich [mailto:JBeulich@xxxxxxxx]
>> Sent: 07 September 2018 12:20
>> To: Paul Durrant <Paul.Durrant@xxxxxxxxxx>
>> Cc: Julien Grall <julien.grall@xxxxxxx>; Andrew Cooper
>> <Andrew.Cooper3@xxxxxxxxxx>; George Dunlap
>> <George.Dunlap@xxxxxxxxxx>; Jun Nakajima <jun.nakajima@xxxxxxxxx>;
>> Stefano Stabellini <sstabellini@xxxxxxxxxx>; xen-devel <xen-
>> devel@xxxxxxxxxxxxxxxxxxxx>
>> Subject: Re: [PATCH v6 09/14] mm / iommu: include need_iommu() test in
>> iommu_use_hap_pt()
>> 
>> >>> On 23.08.18 at 11:47, <paul.durrant@xxxxxxxxxx> wrote:
>> > The name 'iommu_use_hap_pt' suggests that that P2M table is in use as
>> the
>> > domain's IOMMU pagetable which, prior to this patch, is not strictly true
>> > since the macro did not test whether the domain actually has IOMMU
>> > mappings.
>> 
>> Hmm, I would never have implied "has IOMMU mappings" from this
>> variable name. To me it has always been "use HAP page tables for
>> IOMMU if an IOMMU is in use". The code change looks sane, but
>> I'm not sure it is a clear improvement. Hence I wonder whether you
>> have a need for this change in subsequent patches which goes
>> beyond what you say above.
>> 
> 
> I could take it out but it would mean a non-trivial rebase, and to me - if 
> true - the name sill implies the IOMMU is in use for the domain so I'd like 
> to 
> keep the change.

Let's broaden the Cc list a little - perhaps we can get further opinions this
way.

Jan



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel