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Bug 1518148 - Fail to attach interface after libvirtd restart
Summary: Fail to attach interface after libvirtd restart
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: libvirt
Version: 7.5
Hardware: Unspecified
OS: Unspecified
unspecified
unspecified
Target Milestone: rc
: ---
Assignee: Ján Tomko
QA Contact: yalzhang@redhat.com
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2017-11-28 10:32 UTC by Jingjing Shao
Modified: 2018-04-10 11:01 UTC (History)
8 users (show)

Fixed In Version: libvirt-3.9.0-5.el7
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
Environment:
Last Closed: 2018-04-10 11:00:58 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)
Problematic vm xml (3.79 KB, text/plain)
2017-12-01 14:04 UTC, yalzhang@redhat.com 		no flags Details
View All


Links
System ID Private Priority Status Summary Last Updated
Red Hat Bugzilla 1434451 0 high CLOSED [RFE] allow to set device alias at XML define time 2021-02-22 00:41:40 UTC
Red Hat Product Errata RHEA-2018:0704 0 None None None 2018-04-10 11:01:32 UTC

Internal Links: 1434451

Description Jingjing Shao 2017-11-28 10:32:44 UTC 
Description of problem:
Fail to attach interface after libvirtd restart

Version-Release number of selected component (if applicable):
libvirt-3.9.0-3.virtcov.el7.x86_64

How reproducible:
100%

Steps to reproduce:
1. Prepare a running guest with info as below
# virsh dumpxml rhel | grep /interface  -B7
    <interface type='network'>
      <mac address='52:54:00:c2:66:40'/>
      <source network='default' bridge='virbr0'/>
      <target dev='vnet0'/>
      <model type='rtl8139'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>


2.Restart the libvirtd
# service libvirtd restart
Redirecting to /bin/systemctl restart libvirtd.service


3. Attach the interface
#  virsh attach-interface rhel network default
error: Failed to attach interface
error: internal error: unable to execute QEMU command 'device_add': Bus 'pci' not found


Actual results:
As the step3 shows


Expected results:
Interface attached successfully


Addtional info:

Test on libvirt-3.9.0-2.el7.x86_64 no such issue
Comment 3 Ján Tomko 2017-11-28 13:53:19 UTC 
Proposed upstream patch:
https://www.redhat.com/archives/libvir-list/2017-November/msg01139.html
Comment 4 Ján Tomko 2017-11-29 14:59:21 UTC 
v2: https://www.redhat.com/archives/libvir-list/2017-November/msg01151.html
Comment 5 Ján Tomko 2017-11-30 16:07:27 UTC 
Pushed upstream as:
commit 309cd46b400d80420615b19adfebf7158492ae3b
    Introduce virDomainDeviceAliasIsUserAlias

commit dacfc6b10bcff1c275d21a37edf0bc83e0947492
    qemu: prefer the PCI bus alias from status XML

commit fdf354fb51e7f00b582d0daa18961d432155df83
    virQEMUCapsHasPCIMultiBus: use def->os.arch

commit 65108d94d093de082dc5a2d4a73844dd569506db
CommitDate: 2017-11-30 16:49:05 +0100

    virQEMUCapsHasPCIMultiBus: assume true if we have no version information

git describe: v3.10.0-rc1-9-g65108d94d
Comment 7 yalzhang@redhat.com 2017-12-01 14:02:05 UTC 
Hi Ján Tomko,

I have test the scratch build with latest qemu-kvm-rhev-2.10.0-10.el7.x86_64 on a new created vm, it works well. 

But on one other vm, the hotplug always fail, coldplug is ok. 
I tried to find the difference between the 2 vm's xml, but can not find any clue. Then I tried on another host with the problematic xml, it still fail with the scratch build.The error message says:

# virsh attach-interface rhel7.4 network default
error: Failed to attach interface
error: internal error: unable to execute QEMU command 'device_add': Bus 'pci.0' does not support hotplugging

And I attached the problematic xml, could you please help to debug?
Comment 8 yalzhang@redhat.com 2017-12-01 14:04:10 UTC 
Created attachment 1361609 [details]
Problematic vm xml

Problematic vm xml
Comment 9 Ján Tomko 2017-12-01 14:10:15 UTC 
ACPI needs to be enabled for PCI hotplug: (I'm not sure if it can work through SHPC without ACPI)
<features>
  <acpi/>
</features>
Comment 10 jiyan 2017-12-04 10:25:56 UTC 
Same issue for virtio input device
https://bugzilla.redhat.com/show_bug.cgi?id=1509866#c11
Comment 12 yalzhang@redhat.com 2018-01-14 07:09:16 UTC 
Test on libvirt-3.9.0-7.el7.x86_64, the bug is fixed. Set it as verified.

1. 
# virsh dumpxml rhel | grep /interface -B9

# systemctl restart libvirtd

# virsh attach-interface rhel network default --model virtio --mac 52:54:00:8f:c2:f1
Interface attached successfully

# virsh dumpxml rhel | grep /interface -B7
    <interface type='network'>
      <mac address='52:54:00:8f:c2:f1'/>
      <source network='default' bridge='virbr0'/>
      <target dev='vnet0'/>
      <model type='virtio'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>

2. restart libvirtd, then attach device with alias name
# systemctl restart libvirtd
# cat inter.xml
<interface type='network'>
      <source network='default' bridge='virbr0'/>
      <model type='virtio'/>
<alias name='ua-myinterface'/>    
</interface>

# virsh attach-device rhel inter.xml 
Device attached successfully

# virsh dumpxml rhel | grep /interface -B7
    <interface type='network'>
      <mac address='52:54:00:8f:c2:f1'/>
      <source network='default' bridge='virbr0'/>
      <target dev='vnet0'/>
      <model type='virtio'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
    <interface type='network'>
      <mac address='52:54:00:2b:bb:d4'/>
      <source network='default' bridge='virbr0'/>
      <target dev='vnet1'/>
      <model type='virtio'/>
      <alias name='ua-myinterface'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x09' function='0x0'/>
    </interface>
Comment 16 errata-xmlrpc 2018-04-10 11:00:58 UTC 
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.

https://access.redhat.com/errata/RHEA-2018:0704
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