On 16.08.2024 13:08, Jiqian Chen wrote: > If run Xen with PVH dom0 and hvm domU, hvm will map a pirq for > a passthrough device by using gsi, see qemu code > xen_pt_realize->xc_physdev_map_pirq and libxl code > pci_add_dm_done->xc_physdev_map_pirq. Then xc_physdev_map_pirq > will call into Xen, but in hvm_physdev_op, PHYSDEVOP_map_pirq > is not allowed because currd is PVH dom0 and PVH has no > X86_EMU_USE_PIRQ flag, it will fail at has_pirq check. > > So, allow PHYSDEVOP_map_pirq when dom0 is PVH and also allow > iPHYSDEVOP_unmap_pirq for the removal device path to unmap pirq. > So that the interrupt of a passthrough device can be successfully > mapped to pirq for domU with a notion of PIRQ when dom0 is PVH. > > To exposing the functionality to wider than (presently) necessary > audience(like PVH domU), so it doesn't add any futher restrictions.
The code change is fine, but I'm struggling with this sentence. I can't really derive what you're trying to say. > And there already are some senarios for domains without > X86_EMU_USE_PIRQ to use these functions. Are there? If so, pointing out an example may help. Jan
