On Mon, 10 Aug 2015 14:22:07 +0800 Jason Wang <jasow...@redhat.com> wrote:
> > > On 08/07/2015 06:49 PM, Cornelia Huck wrote: > > On Fri, 07 Aug 2015 13:07:35 +0800 > > Jason Wang <jasow...@redhat.com> wrote: > > > >>> 2. ring resizing is broken - it actually has a comment: > >>> /* TODO: need a way to put num back on reset. */ > >>> guest that runs out of memory might down-size the ring. > >>> Afterwards, ring size won't come back up after reset - not nice. > >>> > >> Then we need a new field to keep track the original queue size and > >> migrate this. > > virtio-ccw neatly sidesteps it by not implementing ring size changes at > > all :) > > > > But it isn't really all good, see > > > > /* TODO: Add interface to handle vring.num changing */ > > > > We either need to implement this or fence off changing the ring size, I > > guess. > > Yes. > > >>> Given that the modern layout is disabled by default, > >>> I don't think these are release blockers. > >>> > >> Yes and looks like we need a new subsection and transport specific > >> callbacks to fix above? > > Agreed, it's not urgent as virtio-1 is not yet the default (and not > > even enabled for ccw). > > > > I'm not sure we need transport-specific callbacks. Shouldn't the core > > be able to track initial and actual size (and migrate in an optional > > subsection), as long as the transports use defined interfaces to > > interact with it? > > > > For size, I agree it should be tracked by core. But we need also track > transport specific data like dfselect/gfselect for pci. Yup. I'll leave pci data to the pci folks :) I have a patch for handling the size; I'll post it after I've tested it a bit.
