Hi Martin, On Tue, Jan 18, 2022 at 12:12:01AM +0200, Martin Radev wrote: > The virtio_net device is implicitly enabled if user doesn't > explicitly specify that virtio_net is disabled. This is > counter-intuitive to how the rest of the virtio commandline > works. > > For backwards-compatibility, the commandline parameters are > not changed. Instead, this patch prints out a warning if > virtio_net is implicitly enabled. > > Signed-off-by: Martin Radev <martin.b.radev@xxxxxxxxx> > --- > virtio/net.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/virtio/net.c b/virtio/net.c > index 9a25bfa..ab75d40 100644 > --- a/virtio/net.c > +++ b/virtio/net.c > @@ -1002,6 +1002,9 @@ int virtio_net__init(struct kvm *kvm) > > if (kvm->cfg.num_net_devices == 0 && kvm->cfg.no_net == 0) { > static struct virtio_net_params net_params; > + pr_warning( > + "No net devices configured, but no_net not specified. " > + "Enabling virtio_net with default network settings...\n"); I don't think this deserves a warning, as there's nothing inherently wrong with having a default network device. In fact, this is quite helpful for users who want to get a VM up and running without complicated setup. I do agree that at the moment there's nothing to let the user know that a virtio network device is being created, not in the usage synopsis for the lkvm run command, nor in the man page for kvmtool, but I don't think that printing a warning is the solution here. What I suggest is that instead you print the virtual network interface parameters that can be useful for a user to know (like IP address and netmask, or whatever you think might be useful) using pr_debug() after virtio_net__init_one() is called successfully below. Thanks, Alex > > net_params = (struct virtio_net_params) { > .guest_ip = kvm->cfg.guest_ip, > -- > 2.25.1 >