Re: [Qemu-devel] [PATCH 0/3] s390: Fix virtio-scsi IPL quirks

[Cornelia Huck <cohuck@redhat.com>]

On Fri, 6 Apr 2018 14:30:45 +0200
Christian Borntraeger <borntraeger@de.ibm.com> wrote:

> On 04/05/2018 05:07 PM, Viktor Mihajlovski wrote:
> > IPL from virtio-scsi currently uses a non-standard parameter
> > type definition to pass boot parameters from QEMU to the
> > BIOS.
> > 
> > There are two potential issues with this approach:
> > o If the guest operating systems requests a re-ipl of type CCW
> >   where the boot device is a virtio-scsi HBA, this goes unnoticed
> >   by QEMU. The BIOS will detect that it's IPLing from a SCSI
> >   device, but it will boot the first LUN found, which might not
> >   be the one used for the initial boot.
> > o The guest operating system can be confused by an unknown
> >   IPL parameter block type. If the OS hasn't previously used 
> >   diag308 to store the IPL info but is changed to do so, a
> >   user-observable change in behavior will happen.
> > 
> > The following patches address the issues above. 
> > 
> > Viktor Mihajlovski (3):
> >   s390: Refactor IPL parameter block generation
> >   s390: Ensure IPL from SCSI works as expected
> >   s390: Do not pass inofficial IPL type to the guest
> > 
> >  hw/s390x/ipl.c             | 112 ++++++++++++++++++++++++++++++++-------------
> >  pc-bios/s390-ccw/bootmap.c |   7 +++
> >  pc-bios/s390-ccw/iplb.h    |  15 +++++-
> >  3 files changed, 100 insertions(+), 34 deletions(-)
> >   
> 
> Test looks good so far.

OK, I'll queue this to s390-fixes, then. I won't send a pull request
before Monday, so there's still a chance to fix this should problems
show up.

Thanks for testing!