Bug 889932

Summary:	app-containers/docker-20.10.22 requires non-existing CONFIG_MEMCG_SWAP kernel config
Product:	Gentoo Linux	Reporter:	Tim Mohlmann <muhlemmer>
Component:	Current packages	Assignee:	William Hubbs <williamh>
Status:	RESOLVED FIXED
Severity:	normal	CC:	gyakovlev
Priority:	Normal
Version:	unspecified
Hardware:	AMD64
OS:	Linux
URL:	https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=e55b9f96860f6c6026cff97966a740576285e07b
Whiteboard:
Package list:		Runtime testing required:	---
Attachments:	emerge --info output /etc/portage/savedconfig/sys-kernel/gentoo-kernel-6.1.3 /etc/portage/savedconfig/sys-kernel/gentoo-kernel-6.1.3

Description Tim Mohlmann 2023-01-06 10:50:35 UTC

app-containers/docker-20.10.22 requires CONFIG_MEMCG_SWAP kernel configuraton variable to be enabled. There is not such config option in the latest sys-kernel/gentoo-kernel-6.1.3.

Reproducible: Always

Steps to Reproduce:
1. ACCEPT_KEYWORDS="~amd64" emerge \=sys-kernel/gentoo-kernel-6.1.3
2. eselect kernel set linux-6.1.3-gentoo-dist
3. emerge app-containers/docker
4. grep CONFIG_MEMCG_SWAP /etc/portage/savedconfig/sys-kernel/gentoo-kernel-6.1.3

Actual Results:  
After step 3:

 * Messages for package app-containers/docker-20.10.22:
 * Log file: /var/tmp/portage/logs/app-containers:docker-20.10.22:20230105-235121.log

 *   CONFIG_MEMCG_SWAP: is required if you wish to limit swap usage of containers
 * Please check to make sure these options are set correctly.
 * Failure to do so may cause unexpected problems.

Step 4 (grep) returns nothing.

Expected Results:  
Such warning to be omitted if the config option does not exist.

Comment 1 Tim Mohlmann 2023-01-06 10:51:30 UTC

Created attachment 847654 [details]
emerge --info output

Comment 2 Tim Mohlmann 2023-01-06 10:53:03 UTC

Created attachment 847656 [details]
/etc/portage/savedconfig/sys-kernel/gentoo-kernel-6.1.3

Comment 3 Tim Mohlmann 2023-01-06 10:54:40 UTC

Created attachment 847658 [details]
/etc/portage/savedconfig/sys-kernel/gentoo-kernel-6.1.3

Replace previous kernel config attachment, due to wrong mime type detection.

Comment 4 Tim Mohlmann 2023-01-06 11:11:08 UTC

The above URL points to the upstream commit that removed the (unused) CONFIG_MEMCG_SWAP variable as part of the 6.1 release. It also explains why it is obsolete:

> Since 2d1c498072de ("mm: memcontrol: make swap tracking an integral part
> of memory control"), CONFIG_MEMCG_SWAP hasn't been a user-visible config
> option anymore, it just means CONFIG_MEMCG && CONFIG_SWAP

Comment 5 Sam James archtester

2023-01-06 11:15:49 UTC

Thank you for providing analysis as well as the initial report.

Comment 6 Larry the Git Cow gentoo-dev

2023-01-07 19:33:53 UTC

The bug has been closed via the following commit(s):

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=4ecb10dfa3683da470e48d3404bbafc88e43020c

commit 4ecb10dfa3683da470e48d3404bbafc88e43020c
Author:     William Hubbs <williamh@gentoo.org>
AuthorDate: 2023-01-07 19:29:04 +0000
Commit:     William Hubbs <williamh@gentoo.org>
CommitDate: 2023-01-07 19:33:38 +0000

    app-containers/docker: adjust kernel checks
    
    The CONFIG_MEMCG_SWAP kernel option was removed in linux 6.1, so adjust
    the check to account for this.
    
    Closes: https://bugs.gentoo.org/889932
    Signed-off-by: William Hubbs <williamh@gentoo.org>

 app-containers/docker/docker-20.10.22.ebuild | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)