On Tue, Dec 17, 2024, Ashish Kalra wrote: > > > On 12/17/2024 10:00 AM, Dionna Amalie Glaze wrote: > > On Mon, Dec 16, 2024 at 3:57 PM Ashish Kalra <Ashish.Kalra@xxxxxxx> wrote: > >> > >> From: Ashish Kalra <ashish.kalra@xxxxxxx> > > > >> The on-demand SEV initialization support requires a fix in QEMU to > >> remove check for SEV initialization to be done prior to launching > >> SEV/SEV-ES VMs. > >> NOTE: With the above fix for QEMU, older QEMU versions will be broken > >> with respect to launching SEV/SEV-ES VMs with the newer kernel/KVM as > >> older QEMU versions require SEV initialization to be done before > >> launching SEV/SEV-ES VMs. > >> > > > > I don't think this is okay. I think you need to introduce a KVM > > capability to switch over to the new way of initializing SEV VMs and > > deprecate the old way so it doesn't need to be supported for any new > > additions to the interface. > > > > But that means KVM will need to support both mechanisms of doing SEV > initialization - during KVM module load time and the deferred/lazy > (on-demand) SEV INIT during VM launch. What's the QEMU change? Dionna is right, we can't break userspace, but maybe there's an alternative to supporting both models.
