On Wed, Feb 23, 2022 at 06:20:36PM +0000, Robin Murphy wrote: > On 2022-02-23 18:02, Jason Gunthorpe via iommu wrote: > > On Wed, Feb 23, 2022 at 06:00:06PM +0000, Robin Murphy wrote: > > > > > ...and equivalently just set owner_cnt directly to 0 here. I don't see a > > > realistic use-case for any driver to claim the same group more than once, > > > and allowing it in the API just feels like opening up various potential > > > corners for things to get out of sync. > > > > I am Ok if we toss it out to get this merged, as there is no in-kernel > > user right now. > > > > Something will have to come back for iommufd, but we can look at what > > is best suited then. > > If iommufd plans to be too dumb to keep track of whether it already owns a > given group or not, I can't see it dealing with attaching that group to a > single domain no more than once, either ;) Indeed, this is why I'd like to use the device API :) Jason
