nx842 - CRB request time out (-110) when uninstall NX modules and initiate NX request
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
The Ubuntu-power-systems project |
Fix Released
|
Critical
|
Manoj Iyer | ||
linux (Ubuntu) |
Fix Released
|
Critical
|
Manoj Iyer | ||
Bionic |
Fix Released
|
Critical
|
Unassigned |
Bug Description
[Impact]
PowerPC 842 hardware compression support is currently broken, this effects workloads like zswap and others that exploit 842 hardware compression on Power.
[Test]
- Install nx-compress and nx-842-powernv modules
- Initiate NX request
- Uninstall these modules
- Initiate NX request again and we get CRB timeout with error -110
Test kernel available in the PPA, please see comment #4 and please see comment #5 that verifies the PPA kernel works as expected.
[Fix]
IBM has identified that the following upstream patch fixes the issue:
656ecc16e8fc crypto/nx: Initialize 842 high and normal RxFIFO control registers
[Regression Potential]
The patch only impacts the nx-842 modules, only available on PowerPC architecture and does not have any impact on other architectures or generic code. Risk of regression is very low.
[Other Info]
---Problem Description---
Normally nx-compress and nx-842-powernv modules are loaded when selects 842-nx compressor if not loaded and execute forever during system execution. So we will not see this bug in normal case.
But we are seeing NX CRB request timeout when uninstall these modules and load them or select 842-nx compressor.
---uname output---
18.04
Machine Type = P9 system
---Steps to Reproduce---
- Install nx-compress and nx-842-powernv modules
- Initiate NX request
- Uninstall these modules
- Initiate NX request again and we get CRB timeout with error -110
Patches are included in 4.19-rc1
6e708000ec2c93c
656ecc16e8fc2ab
> Looks like the first commit was included in a recent 18.04 update
> (4.15.0-48.51), see
> https:/
>
> but I don't see the second one there yet.
>
> If this is still needed, I would suggest getting this bug mirrored to LP to
> put on Canonical's radar.
We need second commit (656ecc16e8fc2a
CVE References
tags: | added: architecture-ppc64le bugnameltc-166573 severity-medium targetmilestone-inin18041 |
Changed in ubuntu: | |
assignee: | nobody → Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage) |
affects: | ubuntu → linux (Ubuntu) |
Changed in ubuntu-power-systems: | |
importance: | Undecided → Medium |
status: | New → Triaged |
assignee: | nobody → Canonical Kernel Team (canonical-kernel-team) |
Changed in linux (Ubuntu): | |
assignee: | Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage) → Canonical Kernel Team (canonical-kernel-team) |
importance: | Undecided → Medium |
Changed in ubuntu-power-systems: | |
status: | Triaged → Incomplete |
Changed in linux (Ubuntu): | |
status: | New → Incomplete |
Changed in ubuntu-power-systems: | |
status: | Incomplete → Triaged |
Changed in ubuntu-power-systems: | |
importance: | Medium → Critical |
Changed in linux (Ubuntu): | |
importance: | Medium → Critical |
status: | Incomplete → In Progress |
Changed in ubuntu-power-systems: | |
status: | Triaged → In Progress |
Changed in linux (Ubuntu): | |
assignee: | Canonical Kernel Team (canonical-kernel-team) → Manoj Iyer (manjo) |
Changed in ubuntu-power-systems: | |
assignee: | Canonical Kernel Team (canonical-kernel-team) → Manoj Iyer (manjo) |
description: | updated |
Changed in ubuntu-power-systems: | |
status: | In Progress → Fix Committed |
Changed in linux (Ubuntu Bionic): | |
importance: | Undecided → Critical |
status: | New → Fix Committed |
Changed in linux (Ubuntu): | |
status: | Fix Committed → Fix Released |
tags: |
added: verification-done-bionic removed: verification-needed-bionic |
Changed in ubuntu-power-systems: | |
status: | Fix Committed → Fix Released |
tags: | added: cscc |
Next steps: IBM to verify if this issue is already resolved in 19.04, and report back to this bug.