[LU-12803] lustre in staging interferes with 2.12.2 on Ubuntu 18.04

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.13.0, Lustre 2.12.4
• Affects Version/s: Lustre 2.12.2
• Environment: Ubuntu 18.04
• Severity: 3
• Assignee: James A Simmons
• Reporter: James Beal

Description

We have a number of old compute systems which have raid controllers, We are migrating these from a mix of redhat 7.6 and ubuntu 12.04 to ubuntu 18.04. The raid controllers on these systems require kernel modules from the distribution kernel-modules-extra package to function (e.g. to be able to drive the root filesystem device /dev/sda ). 
 
We use dkms packages to install lustre modules

There is a version of lustre in the staging area of the -extra modules package in Ubuntu 18.04. This lustre system has a version of libcfs.ko version 0.7.0 while the libcfs.ko generated from a lustre 2.12.2 source tree has a libcfs.ko version 0.5.0 I have edited the source to bump the version of libcfs.ko to 0.8.0 and that results in a module that works on an 18.04 system with the modules-extra package installed.
 
We need a the source tree to support lustre while the staging modules are available.

For example, inspecting the Ubuntu 18.04 module

root@bc-25-1-02:~# modinfo /lib/modules/4.15.0-64-generic/kernel/drivers/staging/lustre/lnet/libcfs/libcfs.ko
filename:       /lib/modules/4.15.0-64-generic/kernel/drivers/staging/lustre/lnet/libcfs/libcfs.ko
license:        GPL
version:        0.7.0
description:    Lustre helper library
author:         OpenSFS, Inc. <http://www.lustre.org/>
srcversion:     3EAA7DAA70F86FD8F262DC1
depends:
staging:        Y
retpoline:      Y
intree:         Y
name:           libcfs
vermagic:       4.15.0-64-generic SMP mod_unload

Cf the upstream dkms:

root@farm5-head1:~# modinfo /lib/modules/4.15.0-64-generic/updates/dkms/libcfs.ko
filename:       /lib/modules/4.15.0-64-generic/updates/dkms/libcfs.ko
license:        GPL
version:        0.5.0
description:    Lustre helper library
author:         OpenSFS, Inc. <http://www.lustre.org/>
srcversion:     01F59272261BC3745941E9A
depends:
retpoline:      Y
name:           libcfs
vermagic:       4.15.0-64-generic SMP mod_unload

Comments

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch https://review.whamcloud.com/36642/
Subject: LU-12803 libcfs: bump module version
Project: fs/lustre-release
Branch: b2_12
Current Patch Set:
Commit: 75582dbeced0a905bd81530c5a10e2dea4e53bd2

[Gerrit Updater]

Minh Diep ([e-mail]) uploaded a new patch: https://review.whamcloud.com/36642
Subject: LU-12803 libcfs: bump module version
Project: fs/lustre-release
Branch: b2_12
Current Patch Set: 1
Commit: abde594720276a27322d5d64f1214ff67dcf83bc

[Peter Jones]

Landed for 2.13

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch https://review.whamcloud.com/36488/
Subject: LU-12803 libcfs: bump module version
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 4b25d733342bc6f3a424ecfb0db80f1c175a8986

[James Beal]

Can I ask if the chances in the linux kernel are useful, should they be moved foreward ?

[Gerrit Updater]

James Simmons ([e-mail]) uploaded a new patch: https://review.whamcloud.com/36488
Subject: LU-12803 libcfs: bump module version
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: 0c94a5104ad5de5ba568fce075349134d02518c1

[James A Simmons]

The reason for this is that libcfs in the linux kernel is further ahead in its cleanups. I never expected that this would be an issue. Easy fix thankfully.