On Tue, Dec 10, 2024 at 05:28:17PM -0800, Nicolin Chen wrote: > > I would ideally turn it around and provide that range information to > > the kernel and totally ignore the SW_MSI reserved region once > > userspace provides it. > > Hmm.. that sounds like a uAPI for vITS range..but yes..
It controls the window that the kernel uses to dynamically map the ITS pages. > So, VMM can GET_OPTION(SW_MSI) for msi_base to extract the > info from kernel. Likely need a second call for its length? > Since IOMMU_OPTION only supports one val64 input or output. No, just forget about the kernel's SW_MSI region. The VMM uses this API and overrides it and iommufd completely ignores SW_MSI. There is nothing special about the range hard coded into the smmu driver. Jason
