Libvirt provides a portable, long term stable C API for managing the virtualization technologies provided by many operating systems. It includes support for QEMU, KVM, Xen, LXC, bhyve, Virtuozzo, VMware vCenter and ESX, VMware Desktop, Hyper-V, VirtualBox and the POWER Hypervisor.
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Laine Stump cb3fe38c74 util: set MAC address for VF via netlink message to PF+VF# when possible
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1113474

When we set the MAC address of a network device as a part of setting
up macvtap "passthrough" mode (where the domain has an emulated netdev
connected to a host macvtap device that has exclusive use of the
physical device, and sets the device MAC address to match its own,
i.e. "<interface type='direct'> <source mode='passthrough' .../>"), we
use ioctl(SIOCSIFHWADDR) giving it the name of that device. This is
true even if it is an SRIOV Virtual Function (VF).

But, when we are setting the MAC address / vlan ID of a VF in
preparation for "hostdev network" passthrough (this is where we set
the MAC address and vlan id of the VF after detaching the host net
driver and before assigning the device to the domain with PCI
passthrough, i.e. "<interface type='hostdev'>", we do the setting via
a netlink RTM_SETLINK message for that VF's Physical Function (PF),
telling it the VF# we want to change. This sets an "administratively
changed MAC" flag for that VF in the PF's driver, and from that point
on (until the PF driver is reloaded, *not* merely the VF driver) that
VF's MAC address can't be changed using ioctl(SIOCSIFHWADDR) - the
only way to change it is via the PF with RTM_SETLINK.

This means that if a VF is used for hostdev passthrough, it will have
the admin flag set, and future attempts to use that VF for macvtap
passthrough will fail.

The solution to this problem is to check if the device being used for
macvtap passthrough is actually a VF; if so, we use the netlink
RTM_SETLINK message to the PF to set the VF's mac address instead of
ioctl(SIOCSIFHWADDR) directly to the VF; if not, behavior does not
change from previously.

There are three pieces to making this work:

1) virNetDevMacVLan(Create|Delete)WithVPortProfile() now call
   virNetDev(Replace|Restore)NetConfig() rather than
   virNetDev(Replace|Restore)MacAddress() (simply passing -1 for VF#
   and vlanid).

2) virNetDev(Replace|Restore)NetConfig() check to see if the device is
   a VF. If so, they find the PF's name and VF#, allowing them to call
   virNetDev(Replace|Restore)VfConfig().

3) To prevent mixups when detaching a macvtap passthrough device that
   had been attached while running an older version of libvirt,
   virNetDevRestoreVfConfig() is potentially given the preserved name
   of the VF, and if the proper statefile for a VF can't be found in
   the stateDir (${stateDir}/${pfname}_vf${vfid}),
   virNetDevRestoreMacAddress() is called instead (which will look in
   the file named ${stateDir}/${vfname}).

This problem has existed in every version of libvirt that has both
macvtap passthrough and interface type='hostdev'. Fortunately people
seem to use one or the other though, so it hasn't caused any real
world problem reports.
2015-04-21 12:33:20 -04:00
.gnulib@106a3866d0 maint: update to latest gnulib 2015-03-26 09:41:55 -06:00
build-aux bracket-spacing: Add syntax-check for unnecessary curly brackets 2014-11-14 17:13:36 +01:00
daemon daemon: Prefix sysctl configuration filename with a number 2015-04-16 14:39:38 +02:00
docs rng: Move sgio attr definition to a separate block 2015-04-20 10:13:36 +02:00
examples domtop: Properly free cpu status 2015-04-21 10:56:50 +02:00
gnulib maint: fix date in local gnulib patch 2015-01-05 16:44:10 +00:00
include Add VIR_DOMAIN_EVENT_ID_DEVICE_ADDED event 2015-04-15 17:06:01 +02:00
m4 rpm-build: use pkg-config to detect wireshark presence 2015-03-16 22:58:54 +01:00
po Release of libvirt-1.2.14 2015-04-02 15:48:08 +08:00
src util: set MAC address for VF via netlink message to PF+VF# when possible 2015-04-21 12:33:20 -04:00
tests vircapstest: fix build without LXC, QEMU or XEN 2015-04-21 16:53:02 +02:00
tools Add VIR_DOMAIN_EVENT_ID_DEVICE_ADDED event 2015-04-15 17:06:01 +02:00
.ctags maint: Make ctags work out of the box 2013-07-18 08:47:21 +02:00
.dir-locals.el build: avoid tabs that failed syntax-check 2012-09-06 09:43:46 -06:00
.gitignore Revert "src/xenconfig: Xen-xl parser" 2015-01-12 10:15:13 -07:00
.gitmodules make .gnulib a submodule 2009-07-08 16:17:51 +02:00
.mailmap maint: update .mailmap for recent contributions 2015-03-20 06:17:55 -06:00
AUTHORS.in AUTHORS: Add my email address to AUTHORS.in 2015-04-10 18:26:43 +03:00
autobuild.sh Disable libvirtd by default when building on Win32 2014-04-29 11:30:32 +01:00
autogen.sh maint: improve usage of autogen's --no-git 2015-02-06 11:35:29 -07:00
bootstrap maint: update to latest gnulib 2015-03-26 09:41:55 -06:00
bootstrap.conf Revert "bootstrap.conf: add check for flex" 2015-01-12 10:14:30 -07:00
cfg.mk cfg: Disallow usage of 'index' as variable name 2015-04-14 11:18:28 -04:00
ChangeLog-old Fix typos in src/* 2014-04-21 16:49:08 -06:00
config-post.h build: fix build of virt-login-shell on systems with older gnutls 2013-10-22 09:41:50 -06:00
configure.ac configure: Align messages 2015-04-15 13:33:35 +02:00
COPYING maint: follow recommended practice for using LGPL 2013-05-20 14:15:21 -06:00
COPYING.LESSER maint: follow recommended practice for using LGPL 2013-05-20 14:15:21 -06:00
HACKING docs: Fix missing curly braces 2014-12-10 11:21:31 +01:00
libvirt-lxc.pc.in Add pkg-config files for libvirt-qemu & libvirt-lxc 2014-06-23 16:17:27 +01:00
libvirt-qemu.pc.in Add pkg-config files for libvirt-qemu & libvirt-lxc 2014-06-23 16:17:27 +01:00
libvirt.pc.in Add pkg-config files for libvirt-qemu & libvirt-lxc 2014-06-23 16:17:27 +01:00
libvirt.spec.in daemon: Prefix sysctl configuration filename with a number 2015-04-16 14:39:38 +02:00
Makefile.am examples: Introduce domtop 2014-07-18 16:39:54 +02:00
Makefile.nonreentrant maint: use LGPL correctly 2013-05-20 14:03:48 -06:00
mingw-libvirt.spec.in Move virConnect related APIs out of libvirt.h.in 2014-10-24 17:23:51 +01:00
README Correct typos in the documentation (Atsushi SAKAI) 2008-01-24 10:15:13 +00:00
README-hacking docs: update README-hacking 2014-05-06 16:20:24 -06:00
run.in Add PKG_CONFIG_PATH to run.in script. 2014-06-26 14:32:35 +01:00
TODO Update todo list file to point at bugzilla/website 2010-10-13 16:45:26 +01:00

         LibVirt : simple API for virtualization

  Libvirt is a C toolkit to interact with the virtualization capabilities
of recent versions of Linux (and other OSes). It is free software
available under the GNU Lesser General Public License. Virtualization of
the Linux Operating System means the ability to run multiple instances of
Operating Systems concurrently on a single hardware system where the basic
resources are driven by a Linux instance. The library aim at providing
long term stable C API initially for the Xen paravirtualization but
should be able to integrate other virtualization mechanisms if needed.

Daniel Veillard <veillard@redhat.com>