Messages in this thread | | | Date | Tue, 27 Jun 2023 13:01:24 -0300 | From | Jason Gunthorpe <> | Subject | Re: [PATCH v2 00/11] iommufd: Add nesting infrastructure |
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On Tue, Jun 27, 2023 at 06:02:13AM +0000, Tian, Kevin wrote: > > From: Nicolin Chen <nicolinc@nvidia.com> > > Sent: Tuesday, June 27, 2023 1:29 AM > > > > > I'm not sure whether the MSI region needs a special MSI type or > > > just a general RESV_DIRECT type for 1:1 mapping, though. > > > > I don't quite get this part. Isn't MSI having IOMMU_RESV_MSI > > and IOMMU_RESV_SW_MSI? Or does it juset mean we should report > > the iommu_resv_type along with reserved regions in new ioctl? > > > > Currently those are iommu internal types. When defining the new > ioctl we need think about what are necessary presenting to the user. > > Probably just a list of reserved regions plus a flag to mark which > one is SW_MSI? Except SW_MSI all other reserved region types > just need the user to reserve them w/o knowing more detail.
I think I prefer the idea we just import the reserved regions from a devid and do not expose any of this detail to userspace.
Kernel can make only the SW_MSI a mandatory cut out when the S2 is attached.
Jason
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