Comment 6 for bug 1908512

I tested on hirsute and it's working fine.

I don't see meaningful differences between focal and hirsute:

- For the XML

--- ubuntu-server-20.04.1-on-focal.xml 2020-12-17 15:02:28.678279263 +0100
+++ ubuntu-server-20.04.1-on-hirsute.xml 2020-12-17 14:47:50.790210994 +0100
@@ -1,6 +1,6 @@
 <domain type='kvm' id='1'>
   <name>ubuntu-server-20.04.1</name>
- <uuid>65166cc6-7cec-47e3-bd85-390f60a71d01</uuid>
+ <uuid>48ce4792-c557-4e02-a946-a23d23cabf85</uuid>
   <title>ubuntu-server-20.04.1</title>
   <memory unit='KiB'>2097152</memory>
   <currentMemory unit='KiB'>2097152</currentMemory>
@@ -12,7 +12,7 @@
     <partition>/machine</partition>
   </resource>
   <os>
- <type arch='x86_64' machine='pc-i440fx-focal'>hvm</type>
+ <type arch='x86_64' machine='pc-i440fx-hirsute'>hvm</type>
   </os>
   <features>
     <acpi/>
@@ -88,8 +88,8 @@
     </memballoon>
   </devices>
   <seclabel type='dynamic' model='apparmor' relabel='yes'>
- <label>libvirt-65166cc6-7cec-47e3-bd85-390f60a71d01</label>
- <imagelabel>libvirt-65166cc6-7cec-47e3-bd85-390f60a71d01</imagelabel>
+ <label>libvirt-48ce4792-c557-4e02-a946-a23d23cabf85</label>
+ <imagelabel>libvirt-48ce4792-c557-4e02-a946-a23d23cabf85</imagelabel>
   </seclabel>
   <seclabel type='dynamic' model='dac' relabel='yes'>
     <label>+64055:+108</label>

- For the QEMU command lines

--- qemu-cmdline-focal.txt 2020-12-17 15:04:52.973631013 +0100
+++ qemu-cmdline-hirsute.txt 2020-12-17 14:46:24.018597093 +0100
@@ -2,12 +2,12 @@
 -name guest=ubuntu-server-20.04.1,debug-threads=on
 -S
 -object secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-1-ubuntu-server-20.04./master-key.aes
--machine pc-i440fx-focal,accel=kvm,usb=off,dump-guest-core=off
+-machine pc-i440fx-hirsute,accel=kvm,usb=off,dump-guest-core=off
 -cpu qemu64
 -m 2048
 -overcommit mem-lock=off
 -smp 4,sockets=4,cores=1,threads=1
--uuid 65166cc6-7cec-47e3-bd85-390f60a71d01
+-uuid 48ce4792-c557-4e02-a946-a23d23cabf85
 -no-user-config
 -nodefaults
 -chardev socket,id=charmonitor,fd=31,server,nowait

So, it may be a qemu issue?