Comment 19 for bug 1830243

Got signed kernels from xnox in [1].
With those they zipl

Using config file '/etc/zipl.conf'
Target device information
  Device..........................: fc:00
  Partition.......................: fc:01
  Device name.....................: vda
  Device driver name..............: virtblk
  Type............................: disk partition
  Disk layout.....................: SCSI disk layout
  Geometry - start................: 2048
  File system block size..........: 4096
  Physical block size.............: 512
  Device size in physical blocks..: 16775135
Building bootmap in '/boot'
Adding IPL section 'ubuntu' (default)
  initial ramdisk...: /boot/initrd.img-5.2.0-1-generic
  signature for.....: /lib/s390-tools/stage3.bin
  kernel image......: /boot/vmlinuz-5.2.0-1-generic
  signature for.....: /boot/vmlinuz-5.2.0-1-generic
  kernel parmline...: 'root=LABEL=cloudimg-rootfs'
  component address:
    heap area.......: 0x00002000-0x00005fff
    stack area......: 0x0000f000-0x0000ffff
    internal loader.: 0x0000a000-0x0000efff
    parameters......: 0x00009000-0x000091ff
    kernel image....: 0x00010000-0x004b8fff
    parmline........: 0x004ba000-0x004ba1ff
    initial ramdisk.: 0x004c0000-0x01622bff
Preparing boot device: vda (0000).
Detected SCSI PCBIOS disk layout.
Writing SCSI master boot record.
Syncing disks...
Done.

With that starting the guest gave either
  2019-07-05 10:17:06.535+0000: shutting down, reason=crashed
or
  ! No EXEC entry !

With the qemu from PPA [2] things work again.
I can go forward with the SRU on this, thanks for your help everybody.

P.S. I have a few other changes I want to bundle, so I beg your pardon for a few days extra delay. But this isn't urgent until the signed kernels would land so that should be ok.

[1]: https://launchpad.net/~xnox/+archive/ubuntu/scratch
[2]: https://launchpad.net/~paelzer/+archive/ubuntu/bug-1830243-secure-boot-toleration