On Tue, Dec 30, 2025 at 06:33:20PM -0800, Paul B. Henson wrote: > I'm running an openbsd vm under libvirt and trying to understand the > current state of virtio-serial support, which is required for > integrating the qemu-agent with libvirt. > > One of the devices seen during boot is: > > virtio2 at pci4 dev 0 function 0 "Qumranet Virtio 1.x Console" rev 0x01 > virtio2: no matching child driver; not configured > > which I think is the virtio-serial port, which is also known as > "virtio-console" from what I can tell. > > There's a man page for viocon which is described as the "VirtIO console > device" that "provides serial ports that are attached as ttys". > > This sounds like it would be used for the virtio-serial port qemu > creates for the qemu-agent connection, but it doesn't seem to associate > with the virtio device. > > Is viocon a driver for something else? Am I missing something obvious? > Ah, it seems I am: > > sys/arch/amd64/conf/GENERIC:#viocon* at virtio? # Virtio console > device > > It appears the driver isn't enabled in the default kernel config. While > the devices used by it are created by default? > > crw-rw---- 1 root dialer 94, 0 Dec 28 22:02 /dev/ttyVI00 > crw-rw---- 1 root dialer 94, 10 Dec 28 22:02 /dev/ttyVI10 > crw-rw---- 1 root dialer 94, 20 Dec 28 22:02 /dev/ttyVI20 > crw-rw---- 1 root dialer 94, 30 Dec 28 22:02 /dev/ttyVI30 > crw-rw---- 1 root dialer 94, 40 Dec 28 22:02 /dev/ttyVI40 > > Is the driver not production ready? Or just not used enough to make it > worth enabling by default? > > Thanks much... >
sf@ - It looks like this has been part of the tree but disabled for 10+ years? What is the status of this device? It's been disabled since it was in sys/dev/pci, from r1.1 onward (see below) Should we remove this if it's dead code? Or finish it? Or enable it if it was finished but someone forgot to enable it? -ml ---------------------------- revision 1.1 date: 2015/12/21 22:15:53; author: sf; state: Exp; commitid: cGnF71DnMad8EDT2; add virtio-console driver This patch adds a new driver for use of virtio-console devices as ttys. It's still in an early state and not compiled by default, yet. Currently it is only wired into amd64. i386 is still missing. Discussed with uebayasi@, deraadt@

