Require improved hypervisor detection patch in Ubuntu 18.04
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Ubuntu on IBM z Systems |
Fix Released
|
High
|
Canonical Kernel Team | ||
linux (Ubuntu) |
Fix Released
|
Undecided
|
Skipper Bug Screeners | ||
Bionic |
Fix Released
|
Undecided
|
Po-Hsu Lin |
Bug Description
== Justification ==
The s390x early machine detection code check will set all the uknown
hypervisors to z/VM, this will cause crash for any non KVM, z/VM
system.
== Fixes ==
03aa047e (s390/early: improve machine detection)
Patch can be cherry-picked into Bionic kernel.
Instead of setting all the other hypervisors to z/VM, it will only set
MACHINE_FLAG_VM if it matches the case.
== Tests ==
A test kernel could be found here:
https:/
Boot tested on a s390x KVM node and verified by IBM as well.
== Regression Potential ==
Low, this just improves the detection logic and the changes are
specific to s390x.
== Original Bug Report ==
This kernel commit is requested to be included into the bionic's 4.15.0 LTS kernel:
s390/early: improve machine detection
Right now the early machine detection code check stsi 3.2.2 for "KVM"
and set MACHINE_IS_VM if this is different. As the console detection
uses diagnose 8 if MACHINE_IS_VM returns true this will crash Linux
early for any non z/VM system that sets a different value than KVM.
So instead of assuming z/VM, do not set any of MACHINE_IS_LPAR,
MACHINE_IS_VM, or MACHINE_IS_KVM.
This is required for a dedicated SSC exploiter
CVE References
tags: | added: architecture-s39064 bugnameltc-177777 severity-medium targetmilestone-inin18041 |
Changed in ubuntu: | |
assignee: | nobody → Skipper Bug Screeners (skipper-screen-team) |
affects: | ubuntu → linux (Ubuntu) |
Changed in ubuntu-z-systems: | |
importance: | Undecided → Medium |
status: | New → Triaged |
importance: | Medium → High |
Changed in ubuntu-z-systems: | |
assignee: | nobody → Canonical Kernel Team (canonical-kernel-team) |
Changed in ubuntu-z-systems: | |
status: | Incomplete → Triaged |
description: | updated |
Changed in linux (Ubuntu Bionic): | |
assignee: | nobody → Po-Hsu Lin (cypressyew) |
status: | New → In Progress |
Changed in ubuntu-z-systems: | |
status: | Triaged → In Progress |
Changed in linux (Ubuntu Bionic): | |
status: | In Progress → Fix Committed |
Changed in ubuntu-z-systems: | |
status: | In Progress → Fix Committed |
Changed in linux (Ubuntu): | |
status: | New → Fix Committed |
------- Comment From <email address hidden> 2019-05-22 08:57 EDT-------
Increased severity to high