On (Wed) Jun 24 2009 [18:50:02], Jamie Lokier wrote: > Amit Shah wrote: > > On (Wed) Jun 24 2009 [17:40:49], Jamie Lokier wrote: > > > Amit Shah wrote: > > > > A few sample uses for a vmchannel are to share the host and guest > > > > clipboards (to allow copy/paste between a host and a guest), to > > > > lock the screen of the guest session when the vnc viewer is closed, > > > > to find out which applications are installed on a guest OS even when > > > > the guest is powered down (using virt-inspector) and so on. > > > > > > Those all look like useful features. > > > > > > Can you run an application to provide those features on a guest which > > > _doesn't_ have a vmchannel/virtio-serial support in the kernel? > > > > > > Or will it be restricted only to guests which have QEMU-specific > > > support in their kernel? > > > > libguestfs currently uses the -net user based vmchannel interface that > > exists in current qemu. That doesn't need a kernel that doesn't have > > support for virtio-serial. > > That's great! > > If that works fine, and guest apps/libraries are using that as a > fallback anyway, what benefit do they get from switching to > virtio-serial when they detect that instead, given they still have > code for the -net method? Speed is the biggest benefit. > Is the plan to remove -net user based support from libguestfs? I don't know what Richard's plan is, but if the kernel that libguestfs deploys in the appliance gains support for virtio-serial, there's no reason it shouldn't switch. > Is virtio-serial significantly simpler to use? I think the interface from the guest POV stays the same: reads / writes to char devices. With virtio-serial, though, we can add a few other interesting things like names to ports, ability to hot-add ports on demand, request notifications when either end goes down, etc. Amit -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
