On Thu, Dec 21, 2017 at 01:37:29PM +0200, Yan Vugenfirer wrote: > > > On 20 Dec 2017, at 17:00, Michael S. Tsirkin <[email protected]> wrote: > > > > On Thu, Dec 14, 2017 at 03:31:54PM -0500, Jason Baron wrote: > >> Hi, > >> > >> We have found it useful to have the virtio net device export a linkspeed > >> and duplex setting, such that a guest linkspeed and duplex settings can > >> be set automatically from the host side. We have some guest software > >> that relies on this setting, and fails without a valid value provided. > > > > That software really should be fixed btw. You can't always reliably > > figure out the speed, and it might change at any time. > > > Good point. Each time when there is a linked up indication from the host, we > should expect that the settings can be different (for example backend > changed).
Interesting. So far the motivation was just to trick some proprietary software, for that a static field might be enough. If not - what is the motivation exactly? > >> Thus, I would like to propose adding a new feature bit: > >> > >> VIRTIO_NET_F_SPEED_DUPLEX (4) Device provides a linkspeed and duplex > >> setting > > > > > > I think a high feature bit would be better. Low bits can be > > backported to legacy devices, so better used for things > > like mtu, where communication just breaks otherwise, > > and for net we are running out of these. > > > > > >> I have provided sample qemu hypervisor and linux kernel guest code to > >> implement this feature here: > >> > >> http://lkml.iu.edu/hypermail/linux/kernel/1712.1/05692.html > >> > >> Thanks, > >> > >> -Jason > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [email protected] > > For additional commands, e-mail: [email protected] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
