Comment 11 for bug 2059272

Verification done on jammy-proposed.
---

Part 1: comment #2, libvirt starts without errors, and can list and manage the domain.
Part 2: comment #5, libvirt restarts without errors 100 times with 10 domains.

Environment:
---

LXD virtual machine

 lxc launch --vm ubuntu:jammy lp2059272-jammy
 lxc exec lp2059272-jammy -- su - ubuntu

Enable -proposed

 sudo add-apt-repository -yp proposed

 cat <<EOF | sudo tee /etc/apt/preferences.d/proposed
 Package: *
 Pin: release a=jammy-proposed
 Pin-Priority: 400
 EOF

Install

 sudo apt install -y -t jammy-proposed libvirt-daemon libvirt-daemon-system libvirt-daemon-driver-qemu
 sudo apt install -y gdb qemu-system-x86

 $ apt-cache policy libvirt-daemon
 libvirt-daemon:
   Installed: 8.0.0-1ubuntu7.9
   Candidate: 8.0.0-1ubuntu7.9
   Version table:
  *** 8.0.0-1ubuntu7.9 400
  400 http://security.ubuntu.com/ubuntu jammy-proposed/main amd64 Packages
  400 http://archive.ubuntu.com/ubuntu jammy-proposed/main amd64 Packages
  100 /var/lib/dpkg/status
      8.0.0-1ubuntu7.8 500
  500 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 Packages
      8.0.0-1ubuntu7.5 500
  500 http://security.ubuntu.com/ubuntu jammy-security/main amd64 Packages
      8.0.0-1ubuntu7 500
  500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages

Part 1:
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GDB
...

Check there are 2 threads: cleanup and domain status XML save

 (gdb) i th
   Id Target Id Frame
   1 Thread 0x7fe039120ac0 (LWP 3405) "libvirtd" qemuStateCleanup () at ../../src/qemu/qemu_driver.c:1070
   18 Thread 0x7fe00ffff640 (LWP 3425) "gmain" (running)
   19 Thread 0x7fe00f7fe640 (LWP 3426) "gdbus" (running)
   20 Thread 0x7fe00effd640 (LWP 3473) "udev-event" (running)
   24 Thread 0x7fe014e07640 (LWP 3600) "vm-test-vm" (running)
   25 Thread 0x7fe00dffb640 (LWP 3620) "qemu-event" virDomainObjSave (obj=0x7fe028301a30, xmlopt=0x7fe028040010, statusDir=0x7fe0280373b0 "/run/libvirt/qemu") at ../../src/conf/domain_conf.c:28879

Confirm the qemu driver's domain xml formatter/options is set/referenced:

 (gdb) t 25

 (gdb) p xmlopt.privateData.format
 $1 = (virDomainXMLPrivateDataFormatFunc) 0x7fe0176b4da0 <qemuDomainObjPrivateXMLFormat>

 (gdb) p xmlopt.parent.parent_instance
 $2 = {g_type_instance = {g_class = 0x7fe02806cf20}, ref_count = 1, qdata = 0x0}

Let the cleanup function and shutdown path finish

 (gdb) t 1
 (gdb) c &

 (gdb) t 25

Check the formatter/options again; it is *STILL* referenced:

 (gdb) p xmlopt.privateData.format
 $3 = (virDomainXMLPrivateDataFormatFunc) 0x7fe0176b4da0 <qemuDomainObjPrivateXMLFormat>

 (gdb) p xmlopt.parent.parent_instance
 $4 = {g_type_instance = {g_class = 0x7fe02806cf20}, ref_count = 1, qdata = 0x0}

Check the VM status XML *before* the save function finishes:

 $ sudo grep -e '<domstatus' -e '<domain' -e 'monitor path' /run/libvirt/qemu/test-vm.xml
 <domstatus state='running' reason='booted' pid='3597'>
   <monitor path='/var/lib/libvirt/qemu/domain-1-test-vm/monitor.sock' type='unix'/>
   <domain type='qemu' id='1'>

Let the save function continue, and libvirt finishes shutting down:

 (gdb) c
 ...
 [Inferior 1 (process 3405) exited normally]

Check the VM status XML *after*:

 $ sudo grep -e '<domstatus' -e '<domain' -e 'monitor path' /run/libvirt/qemu/test-vm.xml
 <domstatus state='running' reason='booted' pid='3597'>
   <monitor path='/var/lib/libvirt/qemu/domain-1-test-vm/monitor.sock' type='unix'/>
   <domain type='qemu' id='1'>

It *CONTINUES* to have the 'monitor path' tag/field.

Now, the next time libvirtd starts, it *CORRECTLY* parses that XML:

 $ sudo systemctl start libvirtd.service
 $ journalctl -b -u libvirtd.service | tail | grep error
 $

And libvirt is now aware of the domain, and can manage it:

 $ virsh list
  Id Name State
 -------------------------
  1 test-vm running

 $ virsh destroy test-vm
 Domain 'test-vm' destroyed

Part 2:
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$ for i in {1..100}; do echo restart $i; sudo systemctl restart libvirtd.service; sleep 10; done
restart 1
restart 2
restart 3
...
restart 98
restart 99
restart 100

No errors:

$ journalctl -b -u libvirtd.service | grep -v -e 'systemd' -e 'hostname:' | cut -d' ' -f7- | sort | uniq -c | sort -rn
    106 /var/lib/libvirt/dnsmasq/default.hostsfile
    106 /var/lib/libvirt/dnsmasq/default.addnhosts - 0 names
    106 /etc/hosts - 8 names