Re: [PATCH v1 2/8] iommu: Introduce a new iommu_group_replace_domain() API

[Nicolin Chen]

On Thu, Feb 02, 2023 at 06:21:20PM +0800, Baolu Lu wrote:
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> 
> 
> On 2023/2/2 15:05, Nicolin Chen wrote:
> > +/**
> > + * iommu_group_replace_domain - replace the domain that a group is attached to
> > + * @new_domain: new IOMMU domain to replace with
> > + * @group: IOMMU group that will be attached to the new domain
> > + *
> > + * This API allows the group to switch domains without being forced to go to
> > + * the blocking domain in-between.
> > + *
> > + * If the attached domain is a core domain (e.g. a default_domain), it will act
> > + * just like the iommu_attach_group().
> 
> I am not following above two lines. Why and how could iommufd set a
> core domain to an iommu_group?

Perhaps this isn't the best narrative. What it's supposed to say
is that this function acts as an iommu_attach_group() call if the
device is "detached", yet we have changed the semantics about the
word "detach". So, what should the correct way to write such a
note?

Thanks
Nic