[Pkg-libvirt-maintainers] Bug#1104735: libvirt: cannot restore internal snapshots

[anonym]

Source: libvirt
Version: 11.3.0-1
Severity: normal

Dear Maintainer,

Since I upgraded from libvirt 11.1.0-1 to 11.2.0-2 (and later 11.3.0-1) 
restoring internal snapshots fails:

     error: Failed to revert snapshot foo1
     error: operation failed: load of internal snapshot 'foo1' job 
failed: Device 'libvirt-1-format' is writable but does not support snapshots

Here's a reproducer:

---8<---

qemu-img create -f qcow2 /tmp/foo.qcow2 1G

cat > /tmp/foo.xml <<-EOF
<domain type='kvm'>
   <name>foo</name>
   <memory unit='MiB'>32</memory>
   <os>
     <type arch='x86_64'>hvm</type>
   </os>
   <devices>
     <disk type='file' device='disk'>
       <driver name='qemu' type='qcow2' discard='unmap'/>
       <source file='/tmp/foo.qcow2'/>
       <target dev='vda' bus='virtio'/>
     </disk>
   </devices>
</domain>
EOF

virsh create /tmp/foo.xml
virsh snapshot-create-as foo --name foo1
virsh snapshot-revert foo foo1

--->8---

Cheers!

-- System Information:
Debian Release: trixie/sid
   APT prefers unstable
   APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 6.12.25 (SMP w/20 CPU threads; PREEMPT)
Kernel taint flags: TAINT_UNSIGNED_MODULE
Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled