On Tue, Aug 29, 2017 at 03:53:08PM -0400, Willem de Bruijn wrote: > On Tue, Aug 29, 2017 at 3:42 PM, Michael S. Tsirkin <m...@redhat.com> wrote: > > On Tue, Aug 29, 2017 at 03:35:38PM -0400, Willem de Bruijn wrote: > >> By the way, I have had an unrelated patch outstanding for a while > >> to have virtio-net support the VIRTIO_CONFIG_S_NEEDS_RESET > >> command. Will send that as RFC. > > > > Oh nice. > > Great :) > > > One needs to be careful about locking there which is why > > no devices support that yet. > > I originally wrote it based on the virtnet_reset function introduced > for xdp. Calling this from virtnet_config_changed_work is non trivial, > as virtnet_freeze_down waits until no config worker is running. > > Otherwise, I could not find any constraints on when freeze may be > called, and it largely follows the same path. I hope I didn't miss anything.
The issue is that on freeze processes are not running so we generally know no new packets will arrive (might be wrong for bridging, then it's a bug). On device error you must prevent new skbs from coming in, etc. -- MST
