There's a couple reports of things failing in this area (bug 1259070),
but it's tough to tell what's going wrong without stderr from
qemu-bridge-helper. So let's report stderr in the error message

Couple new examples:

virbr0 is inactive:
internal error: /usr/libexec/qemu-bridge-helper --use-vnet --br=virbr0 --fd=21: failed to communicate with bridge helper: Transport endpoint is not connected
stderr=failed to get mtu of bridge `virbr0': No such device

bridge isn't on the ACL:
internal error: /usr/libexec/qemu-bridge-helper --use-vnet --br=br0 --fd=21: failed to communicate with bridge helper: Transport endpoint is not connected
stderr=access denied by acl file

https://bugzilla.redhat.com/show_bug.cgi?id=1258361

When attaching a disk, controller, or rng using an address type ccw
or s390, we need to ensure the support is provided by both the machine.os
and the emulator capabilities (corollary to unconditional setting when
address was not provided for the correct machine.os and emulator.

For an inactive guest, an addition followed by a start would cause the
startup to fail after qemu_command builds the command line and attempts
to start the guest. For an active guest, libvirtd would crash.

Rather than have different usages of STR function in order to determine
whether the domain is s390-ccw or s390-ccw-virtio, make a single API
which will check the machine.os prefix. Then use the function.

Adds a new interface type using UDP sockets, this seems only applicable
to QEMU but have edited tree-wide to support the new interface type.

The interface type required the addition of a "localaddr" (local
address), this then maps into the following xml and qemu call.

<interface type='udp'>
  <mac address='52:54:00:5c:67:56'/>
  <source address='127.0.0.1' port='11112'>
    <local address='127.0.0.1' port='22222'/>
  </source>
  <model type='virtio'/>
  <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
</interface>

QEMU call:
	-net socket,udp=127.0.0.1:11112,localaddr=127.0.0.1:22222

Notice the xml "local" entry becomes the "localaddr" for the qemu call.

reference:
http://lists.gnu.org/archive/html/qemu-devel/2011-11/msg00629.htmlSigned-off-by: NJonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

We are automatically generating some socket paths for domains, but all
those paths end up in a directory that's the same for multiple domains.
The problem is that multiple domains can each run with different
seclabels (users, selinux contexts, etc.).  The idea here is to create a
per-domain directory labelled in a way that each domain can access its
own unix sockets.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1146886Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Otherwise the error is just

    error: Failed to create domain from test1.xml
    error: failed to retrieve file descriptor for interface: Transport endpoint is not connected

since we don't get a sensible error after the fork.

https://bugzilla.redhat.com/show_bug.cgi?id=1210587  (completed)

When generating the default drive address for a SCSI <disk> device,
check the generated address to ensure it doesn't conflict with a SCSI
<hostdev> address. The <disk> address generation algorithm uses the
<target> "dev" name in order to determine which controller and unit
in order to place the device. Since a SCSI <hostdev> device doesn't
require a target device name, its placement on the guest SCSI address
"could" conflict.  For instance, if a SCSI <hostdev> exists at
controller=0 unit=0 and an attempt to hotplug 'sda' into the guest
made, there would be a conflict if the <hostdev> is already using
/dev/sda.

This reverts commit ede34470, which
was apparently written based on testing performed before commits
1e15be1b and 9a12b6 were pushed upstream. Once those two patches are in
place, commit ede34470 is redundant, and can even cause
incorrect/unexpected behavior when auto-assigning addresses for
virtio-net devices.

Commit e8d55172 updated the domain post-parse to automatically add
pcie-root et al for certain ARM "virt" machinetypes, but didn't update
the function qemuDomainSupportsPCI() which is called later on when we
are auto-assigning PCI addresses and default settings for the PCI
controller <model> and <target> attributes. The result was that PCI
addresses weren't assigned, and the controllers didn't have their
attribute default values set, leading to an error when the domain was
started, e.g.:

  internal error: autogenerated dmi-to-pci-bridge options not set

This patch adds the same check made in the earlier patch to
qemuDomainSupportsPCI(), so that PCI address auto-assignment and
target/model default values will be set.

nwfilter uses iptables and ebtables, which only work properly on
tap-based network connections (*not* on macvtap, for example), but we
just ignore any <filterref> elements for other types of networks,
potentially giving users a false sense of security.

This patch checks the network type and fails/logs an error if any
domain <interface> has a <filterref> when the connection isn't using a
tap device.

This resolves:

  https://bugzilla.redhat.com/show_bug.cgi?id=1180011

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1150484Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

This is backed by the qemu device xio3130-downstream. It can only be
connected to a pcie-switch-upstream-port (x3130-upstream) on the
upstream side.

This controller can be connected only to a port on a
pcie-switch-upstream-port. It provides a single hotpluggable port that
will accept any PCI or PCIe device, as well as any device requiring a
pcie-*-port (the only current example of such a device is the
pcie-switch-upstream-port).

this is backed by the qemu device x3130-upstream. It can only plug
into a pcie-root-port or pcie-switch-downstream-port.

This controller can be connected only to a pcie-root-port or a
pcie-switch-downstream-port (which will be added in a later patch),
which is the reason for the new connect type
VIR_PCI_CONNECT_TYPE_PCIE_PORT. A pcie-switch-upstream-port provides
32 ports (slot=0 to slot=31) on the downstream side, which can only
have pci controllers of model "pcie-switch-downstream-port" plugged
into them, which is the reason for the other new connect type
VIR_PCI_CONNECT_TYPE_PCIE_SWITCH.

This is backed by the qemu device ioh3420.

chassis and port from the <target> subelement are used to store/set the
respective qemu device options for the ioh3420. Currently, chassis is
set to be the index of the controller, and port is set to
"(slot << 3) + function" (per suggestion from Alex Williamson).

This controller can be connected (at domain startup time only - not
hotpluggable) only to a port on the pcie root complex ("pcie-root" in
libvirt config), hence the new connect type
VIR_PCI_CONNECT_TYPE_PCIE_ROOT. It provides a hotpluggable port that
will accept any PCI or PCIe device.

New attributes must be added to the controller <target> subelement for
this - chassis and port are guest-visible option values that will be
set by libvirt with values derived from the controller's index and pci
address information.

This uses the new subelement/attribute in two ways:

1) If a "pci-bridge" pci controller has no chassisNr attribute, it
will automatically be set to the controller's index as soon as the
controller's PCI address is known (during
qemuDomainAssignPCIAddresses()).

2) when creating the commandline for a pci-bridge device, chassisNr
will be used to set qemu's chassis_nr option (rather than the previous
practice of hard-coding it to the controller's index).

This patch provides qemu support for the contents of <model> in
<controller> for the two existing PCI controller types that need it
(i.e. the two controller types that are backed by a device that must
be specified on the qemu commandline):

1) pci-bridge - sets <model> name attribute default as "pci-bridge"

2) dmi-to-pci-bridge - sets <model> name attribute default as
   "i82801b11-bridge".

These both match current hardcoded practice.

The defaults are set at the end of qemuDomainAssignPCIAddresses().
This can't be done earlier because some of the options that will be
autogenerated need full PCI address info for the controller, and
because qemuDomainAssignPCIAddresses() might create extra controllers
which would need default settings added, and that hasn't yet been done
at the time the PostParse callbacks are being run.
qemuDomainAssignPCIAddresses() is still called prior to the XML being
written to disk, though, so the autogenerated defaults are persistent.

qemu capabilities bits aren't checked when the domain is defined, but
rather when the commandline is actually created (so the domain can
possibly be defined on a host that doesn't yet have support for the
given device, or a host different from the one where it will
eventually be run). When the commandline is being generated we compare
the modelName to known qemu device names implementing the given type
of controller, and check the capabilities bit for that device.

virtio-net-pci adapter is capable to use irqfd with vhost-net only in MSI-X
mode, which appears to be available only on PCIe bus, at least on ARM
Signed-off-by: NPavel Fedin <p.fedin@samsung.com>

Legacy -net option works correctly only with embedded device models, which
do not require any bus specification. Therefore, we should use -device for
PCI hardware
Signed-off-by: NPavel Fedin <p.fedin@samsung.com>

Rather than provide a somewhat generic error message when the API
returns false, allow the caller to supply a "report = true" option
in order to cause virReportError's to describe which of the 3 paths
that can cause failure.

Some callers don't care about what caused the failure, they just want
to have a true/false - for those, calling with report = false should
be sufficient.

PowerPC pseries based VMs do not support a floppy disk controller.
This prohibits libvirt from creating qemu command with floppy device.
Signed-off-by: NKothapally Madhu Pavan <kmp@linux.vnet.ibm.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1180486Signed-off-by: NJán Tomko <jtomko@redhat.com>

This loop occurs just after we've assured that all devices that
require a PCI device have been assigned and all necessary PCI
controllers have been added. It is the perfect place to add other
potentially auto-generated PCI controller attributes that are
dependent on the controller's PCI address (upcoming patch).

There is a convenient loop through all controllers at the end of the
function, but the patch to add new functionality will be cleaner if we
first rearrange that loop a bit.

Note that the loop originally was accessing info.addr.pci.bus prior to
determining that the pci part of the object was valid. This isn't
dangerous in any way, but seemed a bit ugly, so I fixed it.

This reverts commit 7b401c3b.

Until libvirt is able to differentiate whether heads='1' is just a
leftover from previous libvirt or whether that's added by user on
purpose and also whether the domain was started with the support for
qxl's max_outputs, we cannot incorporate this patch into the tree
due to compatibility reasons.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Allows to specify maximum number of head to QXL driver.

Actually can be a compatiblity problem as heads in the XML configuration
was set by default to '1'.
Signed-off-by: NFrediano Ziglio <fziglio@redhat.com>

For s390-ccw-virtio machines the default bus type is set to ccw.
Specifing an address element allows to override the default.
Signed-off-by: NBoris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: NJason J. Herne <jjherne@us.ibm.com>
Reviewed-by: NStefan Zimmermann <stzi@linux.vnet.ibm.com>

Adding the recently in qemu added 9pfs support for virtio-ccw.
Signed-off-by: NBoris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: NJason J. Herne <jjherne@us.ibm.com>
Reviewed-by: NStefan Zimmermann <stzi@linux.vnet.ibm.com>

If user passes an invalid address for shared memory device to qemu,
neither libvirt nor qemu will report an error, but qemu will auto assign
a pci address to the shared memory device.
Signed-off-by: NLuyao Huang <lhuang@redhat.com>

As the backend of shmem server is a unix type chr device, save it in
virDomainChrSourceDef, so we can reuse the existing code for chr device.
Signed-off-by: NLuyao Huang <lhuang@redhat.com>

Rename qemuBuildShmemDevCmd to qemuBuildShmemDevStr and change the
return type so that it can be reused in the device hotplug code later.

And split the chardev creation part in a new function
qemuBuildShmemBackendStr for reuse in the device hotplug code later.
Signed-off-by: NLuyao Huang <lhuang@redhat.com>

Signed-off-by: NLuyao Huang <lhuang@redhat.com>

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1165029Signed-off-by: NLuyao Huang <lhuang@redhat.com>

Since QEMU commit ea96bc6 [1]:
i386: drop FDC in pc-q35-2.4+ if neither it nor floppy drives are wanted
the floppy controller is no longer implicit.

Specify it explicitly on the command line if the machine type version
is 2.4 or later.

Note that libvirt's floppy drives do not result in QEMU implying the
controller, because libvirt uses if=none instead of if=floppy.

https://bugzilla.redhat.com/show_bug.cgi?id=1227880

[1] http://git.qemu.org/?p=qemu.git;a=commitdiff;h=ea96bc6

For the implicit controller, we set them via -global.
Separating them will allow reuse for explicit fdc controller as well.

No functional impact apart from one extra allocation.

Also check the device type when deciding what type the address should
be. Commit 9807c471 (aiming to fix another error in address allocation)
only checked the target type, but its value is different for different
device types. This resulted in an error when trying to attach
a channel with target type 'virtio':

error: Failed to attach device from channel-file.xml
error: internal error: virtio serial device has invalid address type

Make the logic for releasing the address dependent only on
* the address type
* whether it was allocated earlier
to avoid copying the device and target type checks.

https://bugzilla.redhat.com/show_bug.cgi?id=1230039Signed-off-by: NLuyao Huang <lhuang@redhat.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1201760

When the domain "<on_crash>coredump-destroy</on_crash>" is set, the
domain wasn't being destroyed, rather it was being rebooted.

Add VIR_DOMAIN_LIFECYCLE_CRASH_COREDUMP_DESTROY to the list of
on_crash types that cause "-no-reboot" to be added to the qemu
command line.

Although defined the same way, fortunately there hadn't been any deviation.
Ensure any assignments to onCrash use VIR_DOMAIN_LIFECYCLE_CRASH_* defs and
not VIR_DOMAIN_LIFECYCLE_* defs

Make sure we only assign the default spicevmc channel name to spicevmc
virtio channels. Caused by commits 3269ee65 and 1133ee2b, which moved
the assignment from XML parsing code to QEMU but failed to keep the
logic.

https://bugzilla.redhat.com/show_bug.cgi?id=1179680Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

When support for the pcie-root and dmi-to-pci-bridge buses on a Q35
machinetype was added, I was concerned that even though qemu at the
time allowed plugging a PCI device into a PCIe port, that it might not
be supported in the future. To prevent painful backtracking in the
possible future where this happened, I disallowed such connections
except in a few specific cases requested by qemu developers (indicated
in the code with the flag VIR_PCI_CONNECT_TYPE_EITHER_IF_CONFIG).

Now that a couple years have passed, there is a clear message from
qemu that there is no danger in allowing PCI devices to be plugged
into PCIe ports. This patch eliminates
VIR_PCI_CONNECT_TYPE_EITHER_IF_CONFIG and changes the code to always
allow PCI->PCIe or PCIe->PCI connection *when the PCI address is
specified in the config. (For newly added devices that haven't yet
been given a PCI address, the auto-placement still prefers using the
correct type of bus).