Package: qemu Version: 1:5.2+dfsg-10 hi,
recently i migrated a windows virtual machine from debian buster to debian bullseye. Libvirt configuration was exactly the same but the booted windows system lost its network connectivity and also deactivated a second attached virtual disk because of policy reasons. The problem would have also appeared if i simply updated the host system from buster to bullseye. Chances are high that this also results in an unbootable virtual machine. Investigation has shown that the following commit in qemu causing the issue is most likely: Commit af1b80ae56c9 ("i386/acpi: fix inconsistent QEMU/OVMF device paths") i havent checked in detail but it seems likely debian ships a qemu version with this change. See following resources for more informations: https://bugzilla.redhat.com/show_bug.cgi?id=1934158 https://github.com/virtio-win/kvm-guest-drivers-windows/issues/592 https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg08484.html bye, -michael