On Mon, Feb 06, 2023 at 06:39:29AM +0000, Tian, Kevin wrote: > > From: Jason Gunthorpe <jgg@xxxxxxxxxx> > > Sent: Friday, February 3, 2023 11:04 PM > > > > On Fri, Feb 03, 2023 at 08:09:30AM +0000, Tian, Kevin wrote: > > > > From: Nicolin Chen <nicolinc@xxxxxxxxxx> > > > > Sent: Thursday, February 2, 2023 3:05 PM > > > > > > > > QEMU with this feature should have the vIOMMU maintain a cache of the > > > > guest io page table addresses and assign a unique IOAS to each unique > > > > guest page table. > > > > > > I didn't get why we impose such requirement to userspace. > > > > I read this as implementation guidance for qemu. qemu can do what it > > wants of course > > > > sure but I still didn't get why this is a guidance specific to the > new replace cmd... I think the guidance is about the change to VFIO uAPI where it is now possible to change the domain attached, previously that was not possible Jason