linux-kernel - Writing "+pids" to cgroup.subtree

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 4 Dec 2017 22:35:13 +0100
From:   "Michael Kerrisk (man-pages)" <mtk.manpages@...il.com>
To:     Tejun Heo <tj@...nel.org>
Cc:     mtk.manpages@...il.com, lkml <linux-kernel@...r.kernel.org>
Subject: Writing "+pids" to cgroup.subtree_control flie yields EINVAL

Hello Tejun,

I was trying to do some simple testing ot the CPU controller
that is merged into 4.15, and ran immediately into some confusion.
In the root cgroup on a freshly booted 4.150-rc1, I try the following:

# pwd
/sys/fs/cgroup/unified
# echo '+cpu' > cgroup.subtree_control 
sh: echo: write error: Invalid argument

What am I missing> I presume I'm missing something obvious, although
nothing jumped out at me as I read the cgroups-v2.txt file.

Cheers,

Michael

-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/