Due to parallel probing of the linux kernel `/dev/sd*` can't be used to
reliably address a hard disk. This can be seen by the many spurious
failures of the dracut CI, where `mdadm` failed with error 524 or tests
failed due to the success marker message written to the wrong disk.
* don't rely on `/dev/sd*` but use disk ids and `/dev/disk/by-id/ata-disk_<name>`
* specify the exact qemu machine architecture `-M q35` needed for the
disk ids. A later patch will move this to `run-qemu`, when all tests are converted
* due to `-M q35` the interface names have changed from
`ens2` -> `enp0s1` and `ens3` -> `enp0s2`
If the host supports kvm, use is. If this is not the case but the kqemu
module is loaded, run qemu with kqemu optimization. Otherwise fall-back to
pure usermode qemu.
Also create the root filesystem from within the virtual env, this way there
will be no nasty suprises w.r.t interactions with the host machine. This
is important when we test booting to LVM, LUKS, and mdraid.
Harald Hoyer