[UBUNTU 23.04] Regression: Ubuntu 23.04/23.10 do not include uvdevice anymore
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Ubuntu on IBM z Systems |
Fix Released
|
Undecided
|
Skipper Bug Screeners | ||
linux (Ubuntu) |
Fix Released
|
Medium
|
Unassigned | ||
Lunar |
Won't Fix
|
Undecided
|
Unassigned | ||
Mantic |
Fix Released
|
High
|
Unassigned | ||
Noble |
Fix Released
|
Medium
|
Unassigned |
Bug Description
---Problem Description---
Regression: uvdevice at /dev/uv not compiled into kernel
Machine Type = IBM z15, IBM z16
Contact Information = <email address hidden>
---uname output---
Linux 6.5.0-14-generic #14-Ubuntu SMP Tue Nov 14 14:16:58 UTC 2023 s390x s390x s390x GNU/Linux
---Debugger---
A debugger is not configured
---Additional Hardware Info---
Secure Execution feature code enabled (optional)
---Steps to Reproduce---
# working/ old behavior
on a fresh ubuntu 22.10 (and 22.04) LPAR/guest1 (with Secure execution available)
> cat /dev/uv
/dev/uv
> cat /boot/config-
CONFIG_
that's the expected state for Ubuntu.
# current/ non expected behavior
since Ubuntu 23.04 the following happens:
stock kernel non-modified, latest available
> cat /dev/uv
cat: /dev/uv: No such file or directory
COMMENT:
this still can happen if the machine has no Secure Execution feature available
However, the following should not be the case under any circumstances:
> cat /boot/config-
# CONFIG_S390_UV_UAPI is not set
Somehow that configuration got lost between 22.X and 23.X.
Maybe, because IIRC that features got back-ported to 22.X
# Proposed Solution:
change the kernel config to
CONFIG_
or
CONFIG_
and provide a new kernel binary
Stack trace output:
n/a
System Dump Info:
The system is not configured to capture a system dump.
Oops output:
n/a
tags: | added: architecture-s39064 bugnameltc-204559 severity-medium targetmilestone-inin--- |
Changed in ubuntu: | |
assignee: | nobody → Skipper Bug Screeners (skipper-screen-team) |
affects: | ubuntu → linux (Ubuntu) |
Changed in linux (Ubuntu Mantic): | |
importance: | Undecided → High |
Changed in linux (Ubuntu Noble): | |
importance: | Undecided → Medium |
Changed in linux (Ubuntu Lunar): | |
status: | New → Won't Fix |
Changed in linux (Ubuntu Noble): | |
assignee: | Skipper Bug Screeners (skipper-screen-team) → nobody |
Changed in ubuntu-z-systems: | |
assignee: | nobody → Skipper Bug Screeners (skipper-screen-team) |
Changed in ubuntu-z-systems: | |
status: | New → In Progress |
Changed in linux (Ubuntu Mantic): | |
status: | In Progress → Fix Committed |
Changed in linux (Ubuntu Noble): | |
status: | In Progress → Fix Committed |
Changed in ubuntu-z-systems: | |
status: | In Progress → Fix Committed |
tags: | removed: verification-needed-mantic-linux |
tags: |
added: targetmilestone-inin2310 removed: targetmilestone-inin--- |
tags: | added: verification-done-mantic-linux |
tags: | added: verification-done |
Changed in ubuntu-z-systems: | |
status: | Fix Committed → Fix Released |
Thanks Steffen for raising this and bringing this to our attention.
That should obviously not have happen, kernel config changes should be propagated to all newer Ubuntu kernel version, until explicitly dropped or modified for any other reason.
It looks like we hit a kind of a race condition here. While setting this option in jammy, the development of mantic just started and it was missed to enable it in the 'unstable' tree at that time.
We are looking into it soon-ish.
I believe that having a kernel in PPA to unblock you is not very helpful, since I think you need that kernel signed with the usual (prod.) signature/key (and not with a test/dev key coming from the PPA).
Since lunar will reach it's eol in less than 2 weeks, we'll ensure that the option is set in mantic onwards.