1.\" $NetBSD: xpci.4,v 1.3 2014/03/18 18:20:39 riastradh Exp $ 2.\" 3.\" Copyright (c) 2011 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Jean-Yves Migeon <jym@NetBSD.org>. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd January 8, 2011 31.Dt XPCI 4 xen 32.Os 33.Sh NAME 34.Nm xpci 35.Nd Xen frontend paravirtualized PCI pass-through driver 36.Sh SYNOPSIS 37.Cd "xpci* at xenbus?" 38.Cd "pci* at xpci?" 39.Sh DESCRIPTION 40The 41.Nm 42driver is the frontend part of the PCI pass-through functionality 43that can be used by 44.Tn Xen 45guest domains to communicate with PCI devices. 46.Pp 47From a guest point of view, 48.Nm 49is similar to a 50.Xr pci 4 51bus, except that the guest talks with the PCI backend driver 52instead of the real physical device directly. 53.Pp 54When the host domain is 55.Nx , 56the 57.Nm 58driver is backed by a 59.Xr pciback 4 60driver within the dom0. 61.Sh SEE ALSO 62.Xr pci 4 , 63.Xr pciback 4 , 64.Xr xenbus 4 65.Sh HISTORY 66The 67.Nm 68driver first appeared in 69.Nx 5.1 . 70.Sh AUTHORS 71.An -nosplit 72The 73.Nm 74driver was written by 75.An Manuel Bouyer Aq Mt bouyer@NetBSD.org . 76.Sh SECURITY CONSIDERATIONS 77As PCI passthrough offers the possibility for guest domains 78to send arbitrary PCI commands to a physical device, this has 79direct impact on the overall stability and security of the system. 80For example, in case of erroneous or malicious commands, the device 81could overwrite physical memory portions, via DMA. 82