Bug 685083

# diff -Nurb vr-rhel6-x86_64-kvm.xml vr-rhel6-x86_64-kvm-shut.xml 
--- vr-rhel6-x86_64-kvm.xml	2011-03-15 17:09:46.434524674 +0800
+++ vr-rhel6-x86_64-kvm-shut.xml	2011-03-15 16:59:22.593712597 +0800
@@ -1,4 +1,4 @@
-<domain type='kvm' id='6'>
+<domain type='kvm'>
   <name>vr-rhel6-x86_64-kvm</name>
   <uuid>697d236f-56a4-0f83-e40e-6b5d93a46415</uuid>
   <memory>524288</memory>
@@ -23,50 +23,35 @@
       <driver name='qemu' type='raw'/>
       <source file='/var/lib/libvirt/images/vr-rhel6-x86_64-kvm'/>
       <target dev='hda' bus='ide'/>
-      <alias name='ide0-0-0'/>
       <address type='drive' controller='0' bus='0' unit='0'/>
     </disk>
     <controller type='ide' index='0'>
-      <alias name='ide0'/>
       <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
     </controller>
     <interface type='network'>
       <mac address='52:54:00:48:a1:db'/>
       <source network='default'/>
-      <target dev='vnet0'/>
       <model type='rtl8139'/>
-      <alias name='net0'/>
       <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
     </interface>
     <serial type='pty'>
-      <source path='/dev/pts/2'/>
       <target port='0'/>
-      <alias name='serial0'/>
     </serial>
-    <console type='pty' tty='/dev/pts/2'>
-      <source path='/dev/pts/2'/>
+    <console type='pty'>
       <target type='serial' port='0'/>
-      <alias name='serial0'/>
     </console>
     <input type='mouse' bus='ps2'/>
-    <graphics type='vnc' port='5900' autoport='yes' keymap='en-us'/>
+    <graphics type='vnc' port='-1' autoport='yes' keymap='en-us'/>
     <sound model='ac97'>
-      <alias name='sound0'/>
       <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
     </sound>
     <video>
       <model type='cirrus' vram='9216' heads='1'/>
-      <alias name='video0'/>
       <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
     </video>
     <memballoon model='virtio'>
-      <alias name='balloon0'/>
       <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
     </memballoon>
   </devices>
-  <seclabel type='dynamic' model='selinux'>
-    <label>system_u:system_r:svirt_t:s0:c765,c889</label>
-    <imagelabel>system_u:object_r:svirt_image_t:s0:c765,c889</imagelabel>
-  </seclabel>
 </domain>

It's caused by the element "<alias>", domain schema XML doesn't has the definition for "<alias>", as they are generated automatically when domain is running, and is ignored when defining a domain.

And as the offline domain xml could be validated successfully.

Close it as NOTABUG.

(In reply to comment #2)
> It's caused by the element "<alias>", domain schema XML doesn't has the
> definition for "<alias>", as they are generated automatically when domain is
> running, and is ignored when defining a domain.
> 
> And as the offline domain xml could be validated successfully.
> 
> Close it as NOTABUG.

no , with no <alias>, it also can not be validated successfully
cat /tmp/test.xml
<domain type='kvm' id='39'>
  <name>rhel6-x86_64</name>
  <uuid>32202e35-d1bd-7f01-fe8d-11c3e181e579</uuid>
  <memory>524288</memory>
  <currentMemory>524288</currentMemory>
  <vcpu cpuset='0-1,3'>4</vcpu>
  <os>
    <type arch='x86_64' machine='rhel6.1.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pae/>
  </features>
  <clock offset='utc'/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw'/>
      <source file='/var/lib/libvirt/images/kvm-rhel6-x86_64'/>
      <target dev='hda' bus='ide'/>
      <address type='drive' controller='0' bus='0' unit='0'/>
    </disk>
    <controller type='ide' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
    </controller>
    <interface type='network'>
      <mac address='52:54:00:90:3c:46'/>
      <source network='default'/>
      <target dev='vnet1'/>
      <model type='rtl8139'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
    <serial type='pty'>
      <source path='/dev/pts/2'/>
      <target port='0'/>
    </serial>
    <console type='pty' tty='/dev/pts/2'>
      <source path='/dev/pts/2'/>
      <target type='serial' port='0'/>
    </console>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='5901' autoport='yes' keymap='en-us'/>
    <sound model='ac97'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </sound>
    <video>
      <model type='cirrus' vram='9216' heads='1'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
    </memballoon>
  </devices>
  <seclabel type='dynamic' model='selinux'>
    <label>system_u:system_r:svirt_t:s0:c375,c692</label>
    <imagelabel>system_u:object_r:svirt_image_t:s0:c375,c692</imagelabel>
  </seclabel>
</domain>

> (In reply to comment #3)
> no , with no <alias>, it also can not be validated successfully
> cat /tmp/test.xml
> </domain>

with this xml, the domain can be defined and started successfully

<imagelabel> lacks a definition in the domain schemas, that's still true
upstream:

paphio:~/libvirt -> grep imagelabel docs/schemas/*.rng
paphio:~/libvirt -> 

Daniel

patch posted to upstream:

http://www.redhat.com/archives/libvir-list/2011-March/msg00938.html

patch committed to upstream

commit 918c8193e228a98ce002e98671cd0f9dcbc04ef2
Author: Osier Yang <jyang>
Date:   Mon Mar 21 15:58:51 2011 +0800

Test it with libvirt-0.9.9-1.el6 and it failed.
The test steps and errors are the same as that in comments 1 and the domain xml is as follows:
# cat vr-rhel6-x86_64-kvm.xml
<domain type='kvm' id='6'>
  <name>vr-rhel6-x86_64-kvm</name>
  <uuid>2ee6db9e-6445-46a4-7c12-622c5436f9da</uuid>
  <memory>524288</memory>
  <currentMemory>524288</currentMemory>
  <vcpu>1</vcpu>
  <os>
    <type arch='x86_64' machine='rhel6.2.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pae/>
  </features>
  <clock offset='utc'/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw'/>
      <source file='/var/lib/libvirt/images/vr-rhel6-x86_64-kvm'/>
      <target dev='hda' bus='ide'/>
      <alias name='ide0-0-0'/>
      <address type='drive' controller='0' bus='0' unit='0'/>
    </disk>
    <controller type='ide' index='0'>
      <alias name='ide0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
    </controller>
    <interface type='network'>
      <mac address='52:54:00:71:f7:b7'/>
      <source network='default'/>
      <target dev='vnet0'/>
      <model type='rtl8139'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
    <interface type='network'>
      <mac address='52:54:00:2a:9c:c0'/>
      <source network='default'/>
      <target dev='vnet1'/>
      <model type='virtio'/>
      <alias name='net1'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </interface>
    <interface type='network'>
      <mac address='52:54:00:90:f4:66'/>
      <source network='default'/>
      <target dev='vnet2'/>
      <model type='virtio'/>
      <alias name='net2'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x08' function='0x0'/>
    </interface>
    <serial type='pty'>
      <source path='/dev/pts/3'/>
      <target port='0'/>
      <alias name='serial0'/>
    </serial>
    <console type='pty' tty='/dev/pts/3'>
      <source path='/dev/pts/3'/>
      <target type='serial' port='0'/>
      <alias name='serial0'/>
    </console>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='5900' autoport='yes' keymap='en-us'/>
    <sound model='ac97'>
      <alias name='sound0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </sound>
    <video>
      <model type='cirrus' vram='9216' heads='1'/>
      <alias name='video0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <alias name='balloon0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
    </memballoon>
  </devices>
  <seclabel type='dynamic' model='selinux' relabel='yes'>
    <label>system_u:system_r:svirt_t:s0:c276,c1008</label>
    <imagelabel>system_u:object_r:svirt_image_t:s0:c276,c1008</imagelabel>
  </seclabel>
</domain>

See comment 3, It's caused by the "alias"es, "alias" is used only by libvirt internally, you won't see it in the persistent XML config. And it's ignored when defining a domain. And IMO it's not right to add "alias" to the device XML schemas,
as it's really an libvirt internal stuff.

The question is how the XML with <alias> was obtained ? If it's the result
of a virsh dump (or API operation) then we need to fix this so that
this doesn't show up (that's a separate bug). If that was obtained
by getting the files from the internal directory of libvirt under /etc/
then if this break validation that's not a bug, as those files are
specific to libvirt and not for user consumption.

Daniel

(In reply to comment #15)
> The question is how the XML with <alias> was obtained ? If it's the result
> of a virsh dump (or API operation) then we need to fix this so that
> this doesn't show up (that's a separate bug). If that was obtained
> by getting the files from the internal directory of libvirt under /etc/
> then if this break validation that's not a bug, as those files are
> specific to libvirt and not for user consumption.
> 
> Daniel

My thought is constast. :)

If the XML file is virsh dump, it's not bug, as 1) we never store <alias> in the persistent conf, 2) it's ignored when defining, even if it exists, so it's meaningless to validate it 3) I can't see a reason to validate the dumped XML which is already worked well with libvirt. Though yes, we don't do RNG validation inside libvirt, bug probaly we will do that in future, right before parsing the XML.

If the XML file is from /etc, it's not bug too, as we don't write any <alias> into
the persistent conf, it must be caused by one copy some running def there. That's not responsiable by libvirt.

Anyway, If it's bug, it's a separate bug.

Hi Daniel,
(In reply to comment #15)
> The question is how the XML with <alias> was obtained ? If it's the result
> of a virsh dump (or API operation) then we need to fix this so that
> this doesn't show up (that's a separate bug). 
If I use virt-xml-validate to check the xml generated by virsh dump of a running guest, it will failed.
You mean I open a new bug for it?

> If that was obtained by getting the files from the internal directory 
> of libvirt under /etc/ then if this break validation that's not a bug, as those files are specific to libvirt and not for user consumption.
> Daniel
If I use virt-xml-validate to check the /etc/libvirt/qemu/${domain_name}.xml, it is ok.

> It's caused by the "alias"es, "alias" is used only by libvirt
> internally, you won't see it in the persistent XML config. And it's ignored
> when defining a domain. And IMO it's not right to add "alias" to the device XML
> schemas, as it's really an libvirt internal stuff.

No, this is incorrect.  <alias> elements *are* part of the public XML schema, intended to be shown to users by dumpxml. Any device can contain an <alias> element or <address> element, or both. They need to be added to the XML.

(In reply to comment #18)
> > It's caused by the "alias"es, "alias" is used only by libvirt
> > internally, you won't see it in the persistent XML config. And it's ignored
> > when defining a domain. And IMO it's not right to add "alias" to the device XML
> > schemas, as it's really an libvirt internal stuff.
> 
> No, this is incorrect.  <alias> elements *are* part of the public XML schema,
> intended to be shown to users by dumpxml. Any device can contain an <alias>
> element or <address> element, or both. They need to be added to the XML.

I agree that <alias> is part of the public XML.  It only makes sense on a running domain (which is why it is ignored when defining an inactive domain, and stripped when exporting dumpxml --inactive), but we have documented API that uses an alias name: at least virDomainOpenConsole.

Therefore, I agree that we need to update the RNG to validate anything that 'virsh dumpxml' outputs, and that this includes adding <alias> support into RNG.

Fair enough, :)

I will post the patch to upstream.

Patches posted to upstream.

commit 487bdbd8e08c7327c15e286a09f9b23abc2b9dae
Author: Osier Yang <jyang>
Date:   Mon Jan 16 17:28:51 2012 +0800

    docs: Expose alias tag in domain RNG schema
    
    Though <alias> is ignored when defining a domain, it can cause
    failure if one validates (e.g. virt-xml-validate) the XML dumped
    from a running domain. This patch expose it in domain RNG schema
    for all the devices which support it.

commit 4447d2cbdf70aa71af19c0b8a9b73b2c2ad4cd7b
Author: Osier Yang <jyang>
Date:   Mon Jan 16 17:17:26 2012 +0800

    docs: Add readonly to filesystem RNG schema
    
    "<readonly/>" is supported by filesystem XML, and also documented.

Verified PASS with libvirt-0.9.10-1.el6.

# virsh list --all
 Id    Name                           State
----------------------------------------------------
 1     rhel62                         running

# virsh dumpxml rhel62
<domain type='kvm' id='1'>
  <name>rhel62</name>
  <uuid>6a6839c3-8b51-125e-262f-f2d384367c49</uuid>
  <memory>1048576</memory>
  <currentMemory>1048576</currentMemory>
  <vcpu>1</vcpu>
  <os>
    <type arch='x86_64' machine='rhel6.2.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pae/>
  </features>
  <clock offset='utc'/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw' cache='none'/>
      <source file='/var/lib/libvirt/images/rhel62.img'/>
      <target dev='vda' bus='virtio'/>
      <alias name='virtio-disk0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
    </disk>
    <controller type='usb' index='0'>
      <alias name='usb0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
    </controller>
    <interface type='network'>
      <mac address='52:54:00:32:3e:2f'/>
      <source network='default'/>
      <target dev='vnet0'/>
      <model type='virtio'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
    <serial type='pty'>
      <source path='/dev/pts/1'/>
      <target port='0'/>
      <alias name='serial0'/>
    </serial>
    <console type='pty' tty='/dev/pts/1'>
      <source path='/dev/pts/1'/>
      <target type='serial' port='0'/>
      <alias name='serial0'/>
    </console>
    <input type='tablet' bus='usb'>
      <alias name='input0'/>
    </input>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='5900' autoport='yes'/>
    <sound model='ich6'>
      <alias name='sound0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </sound>
    <video>
      <model type='cirrus' vram='9216' heads='1'/>
      <alias name='video0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <alias name='balloon0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </memballoon>
  </devices>
  <seclabel type='dynamic' model='selinux' relabel='yes'>
    <label>system_u:system_r:svirt_t:s0:c505,c866</label>
    <imagelabel>system_u:object_r:svirt_image_t:s0:c505,c866</imagelabel>
  </seclabel>
</domain>

save the xml to /tmp/rhel62.xml
# virt-xml-validate /tmp/rhel62.xml 
/tmp/rhel62.xml validates

    Technical note added. If any revisions are required, please edit the "Technical Notes" field
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    New Contents:
No documentation needed.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHSA-2012-0748.html