[20.10 FEAT] KVM: Enable transparent CCW IPL from DASD - qemu part

[bugproxy]

A previous feature has introduced the support for native CCW IPL, which however required the setting of a per-device property to enforce unlimited prefetch. The unconditional prefetch may not reflect the intention of the channel program. This feature removes the necessity to specify the additional property and thus enables Linux IPL from vfio-ccw attached DASDs transparently.

Business Case:
Improve system management for CCW passthrough devices.

Contributes to qemu package.

[Frank Heimes (fheimes)]

Please share the qemu target version this code is going to land in.
And note that it's 'planned' to have qemu-kvm 5.0 in groovy.

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2020-08-24 07:35 EDT-------
Feature available with qemu 5.1

[Christian Ehrhardt  (paelzer)]

That is a great feature to have, glad to see that happening.
We will not go to qemu 5.1 in Ubuntu 20.10 (too many uncertainties so late in the cycle) but instead stay on qemu 5.0 - would you have a list of commits or a backport cherry-pick repository somewhere that I can use.

And BTW, we need to build test and upload this before this Thursday so I hope someone reads this immediately ?! @Frank could you do pings to ensure that?

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2020-08-25 03:46 EDT-------
The IPL fix is completely contained in

commit 24e58a7b1d411627e326144030a20dcf0093fed0
Author: Jared Rossi <email address hidden>
Date: Tue May 12 14:15:35 2020 -0400

vfio-ccw: allow non-prefetch ORBs

[Christian Ehrhardt  (paelzer)]

Thanks!

The code is public, can we mark the bug public as well?

[Christian Ehrhardt  (paelzer)]

The change is Small, Reasonable and Applies as-is.
The comment doesn't mention vfio-ccw boot directly, but that isn't a problem.

The qemu in -proposed is blocked by some systemd test fails anyway.
As the former one won't move anytime soon I'll probably uploaded this soon on top of the current one. Just one set of builds and tests before that.

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2020-08-25 05:34 EDT-------
@Canonical: Yes, the LP can be moved to "Public"

[Christian Ehrhardt  (paelzer)]

Builds and quick tests (on s390x only, as that change is only vfio-ccw) seem ok.
Adding this on top of the current qemu stuck in proposed.

[Christian Ehrhardt  (paelzer)]

qemu (1:5.0-5ubuntu6) groovy; urgency=medium

  * d/p/ubuntu/lp-1887935-vfio-ccw-allow-non-prefetch-ORBs.patch: fix boot
    from vfio-ccw (LP: #1887935)

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2020-08-27 01:27 EDT-------
IBM Bugzilla status->closed, Fix Released with groovy