On Wed, Jan 29, 2025 at 06:49:22PM +0100, Eric Auger wrote: > > If it was overriden inside iommufd then the user told the kernel what > > range to use to override it. I don't need to go back and report back > > to userspace information that it already gave to the kernel.. > > Looks strange to me because info exposed in sysfs is wrong then. What if > someone else relies on this info, either at kernel level through the > get_resv_regions callback or from user space. Nothing else should call get_resv_regions() because VFIO is bound to the device and iommufd owns the domain. We expect some exclusivity here :) sysfs for sw_msi should be understood as reporting the driver recommendation, not anything to do with the current MSI operation of the device. Jason