We have previously effectively ignored all <controller type='ide'>
elements in a domain definition.
On the i440fx-based machinetypes there is an IDE controller that is
included in the chipset and can't be removed (which is the ide
controller with index='0'>), so it makes sense to ignore that one
controller. However, if an i440fx domain definition has a 2nd
controller, nothing catches this error (unless you also have a disk
attached to it, in which case qemu will complain that you're trying to
use the ide controller named "ide1", which doesn't exist), and if any
other type of domain has even a single controller defined, it will be
incorrectly ignored.
Ignoring a bogus controller definition isn't such a big problem, as
long as an error is logged when any disk is attached to that
non-existent controller. But in the case of q35-based machinetypes,
the hardcoded id ("alias" in libvirt terms) of its builtin SATA
controller is "ide", which happens to be the same id as the builtin
IDE controller on i440fx machinetypes. So libvirt creates a
commandline believing that it is connecting the disk to the builtin
(but actually nonexistent) IDE controller, qemu thinks that libvirt
wanted that disk connected to the builtin SATA controller, and
everybody is happy.
Until you try to connect a 2nd disk to the IDE controller. Then qemu
will complain that you're trying to set unit=1 on a controller that
requires unit=0 (SATA controllers are organized differently than IDE
controllers).
After this patch, if a domain has an IDE controller defined for a
machinetype that has no IDE controllers, libvirt will log an error
about the controller itself as it is building the qemu commandline
(rather than a (possible) error from qemu about disks attached to that
controller). This is done by adding IDE to the list of controller
types that are handled in the loop that creates controller command
strings in qemuBuildCommandline() (previously it would *always* skip
IDE controllers). Then qemuBuildControllerDevStr() is modified to log
an appropriate error in the case of IDE controllers.
In the future, if we add support for extra IDE controllers (piix3-ide
and/or piix4-ide) we can just add it into the IDE case in
qemuBuildControllerDevStr(). For now, nobody seems anxious to add
extra support for an aging and very slow controller, when there are so
many better options available.
Resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=1176071 (Fedora)
https://bugzilla.redhat.com/show_bug.cgi?id=1142631
This patch resolves a situation where the same "<target dev='$name'...>"
can be used for multiple disks in the domain.
While the $name is "mostly" advisory regarding the expected order that
the disk is added to the domain and not guaranteed to map to the device
name in the guest OS, it still should be unique enough such that other
domblk* type operations can be performed.
Without the patch, the domblklist will list the same Target twice:
$ virsh domblklist $dom
Target Source
------------------------------------------------
sda /var/lib/libvirt/images/file.qcow2
sda /var/lib/libvirt/images/file.img
Additionally, getting domblkstat, domblkerror, domblkinfo, and other block*
type calls will not be able to reference the second target.
Fortunately, hotplug disallows adding a "third" sda value:
$ qemu-img create -f raw /var/lib/libvirt/images/file2.img 10M
$ virsh attach-disk $dom /var/lib/libvirt/images/file2.img sda
error: Failed to attach disk
error: operation failed: target sda already exists
$
BUT, it since 'sdb' doesn't exist one would get the following on the same
hotplug attempt, but changing to use 'sdb' instead of 'sda'
$ virsh attach-disk $dom /var/lib/libvirt/images/file2.img sdb
error: Failed to attach disk
error: internal error: unable to execute QEMU command 'device_add': Duplicate ID 'scsi0-0-1' for device
$
Since we cannot fix this issue at parsing time, the best that can be done so
as to not "lose" a domain is to make the check prior to starting the guest
with the results as follows:
$ virsh start $dom
error: Failed to start domain $dom
error: XML error: target 'sda' duplicated for disk sources '/var/lib/libvirt/images/file.qcow2' and '/var/lib/libvirt/images/file.img'
$
Running 'make check' found a few more instances in the tests where this
duplicated target dev value was being used. These also exhibited some
duplicated 'id=' values (negating the uniqueness argument of aliases) in
the corresponding .args file and of course the *xmlout version of a few
input XML files.
In general, we try to make virt-xml-validate tolerant of input
elements in any order when possible. However, as written, the
RNG grammar did not permit <source> unless there was an explicit
type= attribute (even though the C code manages just fine by
defaulting to type='file'). After making the attribute optional
on the 'file' branch, I noticed that the use of diskspec was now
redundant with the branch when no <source> was supplied.
View this patch with 'git diff -b' for a better picture of the
schema change.
* docs/schemas/domaincommon.rng (disk): Hoist 'diskspec' out of
choice, make type='file' default, and still preserve interleave.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-source-pool.xml:
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-discard.xml:
New files.
* tests/qemuxml2argvdata/qemuxml2argv-disk-source-pool.xml:
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-discard.xml:
Reorder XML.
* tests/qemuxml2xmltest.c (mymain): Cover new files.
Signed-off-by: Eric Blake <eblake@redhat.com>
Libvirtd would crash if a domain contained an empty cdrom drive of
type='volume' as the disk def->srcpool member would be dereferenced. Fix
it by checking if the source pool is present before dereferencing it.
Also alter tests to catch this issue in the future.
Reported by: Kevin Shanahan
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1056328
<controller type='pci' index='0' model='pci-root'/>
is auto-added to pc* machine types.
Without this controller PCI bus 0 is not available and
no PCI addresses are assigned by default.
Since older libvirt supported PCI bus 0 even without
this controller, it is removed from the XML when migrating.
With this patch, one can specify the disk source using libvirt
storage like:
<disk type='volume' device='disk'>
<driver name='qemu' type='raw' cache='none'/>
<source pool='default' volume='fc18.img'/>
<target dev='vdb' bus='virtio'/>
</disk>
"seclabels" and "startupPolicy" are not supported for this new
disk type ("volume"). They will be supported in later patches.
docs/formatdomain.html.in:
* Add documents for new XMLs
docs/schemas/domaincommon.rng:
* Add rng for new XMLs;
src/conf/domain_conf.h:
* New struct for 'volume' type disk source (virDomainDiskSourcePoolDef)
* Add VIR_DOMAIN_DISK_TYPE_VOLUME for enum virDomainDiskType
src/conf/domain_conf.c:
* New helper virDomainDiskSourcePoolDefParse to parse the 'volume'
type disk source.
* New helper virDomainDiskSourcePoolDefFree to free the source def
if 'volume' type disk.
tests/qemuxml2argvdata/qemuxml2argv-disk-source-pool.xml:
tests/qemuxml2xmltest.c:
* New test
