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 def31e4c58 qemu: fix attach/detach of netdevs with matching mac addrs
This resolves:

   https://bugzilla.redhat.com/show_bug.cgi?id=862515

which describes inconsistencies in dealing with duplicate mac
addresses on network devices in a domain.

(at any rate, it resolves *almost* everything, and prints out an
informative error message for the one problem that isn't solved, but
has a workaround.)

A synopsis of the problems:

1) you can't do a persistent attach-interface of a device with a mac
address that matches an existing device.

2) you *can* do a live attach-interface of such a device.

3) you *can* directly edit a domain and put in two devices with
matching mac addresses.

4) When running virsh detach-device (live or config), only MAC address
is checked when matching the device to remove, so the first device
with the desired mac address will be removed. This isn't always the
one that's wanted.

5) when running virsh detach-interface (live or config), the only two
items that can be specified to match against are mac address and model
type (virtio, etc) - if multiple netdevs match both of those
attributes, it again just finds the first one added and assumes that
is the only match.

Since it is completely valid to have multiple network devices with the
same MAC address (although it can cause problems in many cases, there
*are* valid use cases), what is needed is:

1) remove the restriction that prohibits doing a persistent add of a
netdev with a duplicate mac address.

2) enhance the backend of virDomainDetachDeviceFlags to check for
something that *is* guaranteed unique (but still work with just mac
address, as long as it yields only a single results.

This patch does three things:

1) removes the check for duplicate mac address during a persistent
netdev attach.

2) unifies the searching for both live and config detach of netdevices
in the subordinate functions of qemuDomainModifyDeviceFlags() to use the
new function virDomainNetFindIdx (which matches mac address and PCI
address if available, checking for duplicates if only mac address was
specified). This function returns -2 if multiple matches are found,
allowing the callers to print out an appropriate message.

Steps 1 & 2 are enough to fully fix the problem when using virsh
attach-device and detach-device (which require an XML description of
the device rather than a bunch of commandline args)

3) modifies the virsh detach-interface command to check for multiple
matches of mac address and show an error message suggesting use of the
detach-device command in cases where there are multiple matching mac
addresses.

Later we should decide how we want to input a PCI address on the virsh
commandline, and enhance detach-interface to take a --address option,
eliminating the need to use detach-device

* src/conf/domain_conf.c
* src/conf/domain_conf.h
* src/libvirt_private.syms
  * added new virDomainNetFindIdx function
  * removed now unused virDomainNetIndexByMac and
    virDomainNetRemoveByMac

* src/qemu/qemu_driver.c
  * remove check for duplicate max from qemuDomainAttachDeviceConfig
  * use virDomainNetFindIdx/virDomainNetRemove instead
    of virDomainNetRemoveByMac in qemuDomainDetachDeviceConfig
  * use virDomainNetFindIdx instead of virDomainIndexByMac
    in qemuDomainUpdateDeviceConfig

* src/qemu/qemu_hotplug.c
  * use virDomainNetFindIdx instead of a homespun loop in
    qemuDomainDetachNetDevice.

* tools/virsh-domain.c: modified detach-interface command as described
    above
2012-10-26 20:47:54 -04:00
.gnulib@d245e6ddd6 maint: update to latest gnulib 2012-10-22 20:25:44 -06:00
build-aux maint: fix up copyright notice inconsistencies 2012-09-20 16:30:55 -06:00
daemon build: check for pod errors 2012-10-26 15:13:39 -06:00
docs documentation: HTML tag fix 2012-10-26 09:53:41 -04:00
examples tests: Fix domain-events python test 2012-10-16 16:37:29 +02:00
gnulib build: fix fresh checkout on RHEL5 2012-04-19 17:11:43 -06:00
include libvirt.h.in: Add new cpumap macro VIR_CPU_USED 2012-10-23 18:48:04 -06:00
m4 build: improve FORTIFY_SOURCE usage 2012-10-23 14:00:32 -06:00
po Implement CPU model driver for PowerPC 2012-10-17 10:03:34 +02:00
python maint: consistent whitespace after 'if' 2012-10-25 11:36:43 -06:00
src qemu: fix attach/detach of netdevs with matching mac addrs 2012-10-26 20:47:54 -04:00
tests bitmap: add virBitmapCountBits 2012-10-25 11:19:23 -06:00
tools qemu: fix attach/detach of netdevs with matching mac addrs 2012-10-26 20:47:54 -04:00
.dir-locals.el build: avoid tabs that failed syntax-check 2012-09-06 09:43:46 -06:00
.gitignore maint: Sort .gitignore 2012-10-26 14:39:55 +02:00
.gitmodules make .gnulib a submodule 2009-07-08 16:17:51 +02:00
.mailmap Autogenerate AUTHORS 2012-10-19 12:44:56 -04:00
AUTHORS.in Remove a couple duplicates from AUTHORS.in 2012-10-22 16:19:38 -04:00
autobuild.sh Switch automated builds to use Mingw64 toolchain instead of Mingw32 2012-06-25 10:41:10 +01:00
autogen.sh build: avoid infinite autogen loop 2012-10-01 09:47:38 -06:00
bootstrap maint: regenerate bootstrap 2012-07-27 09:34:04 -06:00
bootstrap.conf Autogenerate AUTHORS 2012-10-19 12:44:56 -04:00
cfg.mk Autogenerate AUTHORS 2012-10-19 12:44:56 -04:00
ChangeLog-old virterror.c: Fix several spelling mistakes 2012-02-03 11:32:51 -07:00
configure.ac Fix disabling of apparmor/selinux security drivers 2012-10-23 08:56:03 +02:00
COPYING.LIB remove all trailing blank lines 2009-07-16 15:06:42 +02:00
HACKING Various typos and misspellings 2012-10-12 00:03:43 +02:00
libvirt.pc.in build: silence warning from autoconf 2012-05-30 09:22:02 -06:00
libvirt.spec.in spec: Fix multilib issue with systemtap tapsets 2012-10-22 16:15:12 -04:00
Makefile.am Autogenerate AUTHORS 2012-10-19 12:44:56 -04:00
Makefile.nonreentrant Ban use of all inet_* functions 2010-10-22 11:59:23 +01:00
mingw-libvirt.spec.in parallels: add driver skeleton 2012-08-01 11:44:26 +08:00
README Correct typos in the documentation (Atsushi SAKAI) 2008-01-24 10:15:13 +00:00
README-hacking maint: relax git minimum version 2010-02-24 14:29:27 -05:00
run.in syntax-check: fix run.in 2012-09-18 13:59:53 +02:00
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>