$OpenBSD: vio.4,v 1.16 2021/05/24 17:29:56 dv Exp $

Copyright (c) 2012 Stefan Fritsch <sf@sfritsch.de>

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.Dd $Mdocdate: September 24 2015 $ .Dt VIO 4 .Os .Sh NAME .Nm vio .Nd VirtIO network device .Sh SYNOPSIS .Cd "vio* at virtio? flags 0x00" .Sh DESCRIPTION The .Nm driver provides support for the .Xr virtio 4 network interface provided by bhyve, KVM, QEMU, VirtualBox, and .Xr vmd 8 .

p Setting the bit 0x2 in the flags disables the RingEventIndex feature. This can be tried as a workaround for possible bugs in host implementations of .Nm at the cost of slightly reduced performance.

p Setting the bit 0x100 in the flags forces the interface to be always in promiscuous mode. This can be used as a workaround for a bug in QEMU before version 1.7.2 that prevents packets with a VLAN tag from being sent to the guest. .Sh SEE ALSO .Xr intro 4 , .Xr virtio 4 .Sh HISTORY The .Nm driver first appeared in .Ox 5.3 . .Sh AUTHORS .An -nosplit The .Nm driver was ported to .Ox and improved by .An Stefan Fritsch Aq Mt sf@sfritsch.de . It is based on the .Nx .Nm vioif driver by .An Minoura Makoto .