From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Lutomirski Subject: Re: [PATCH 0/2][V2] net: Implement SO_PEERCGROUP to get cgroup of peer Date: Wed, 12 Mar 2014 13:56:28 -0700 Message-ID: <5320C9FC.6070301@amacapital.net> References: <1394657163-7472-1-git-send-email-vgoyal@redhat.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1394657163-7472-1-git-send-email-vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Vivek Goyal , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org Cc: ssorce-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, jkaluza-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, lpoetter-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, kay-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org On 03/12/2014 01:46 PM, Vivek Goyal wrote: > Hi, > > This is V2 of patches. Fixed the function format issue and also I was using > CONFIG_CGROUP instead of CONFIG_CGROUPS. That led to crash at boot. Fixed that. > > Some applications like sssd want to know the cgroup of connected peer over > unix stream socket. They want to use this information to map the cgroup to > the container client belongs to and then decide what kind of policies apply > on the container. > Can you explain what the use case is? My a priori opinion is that this is a terrible idea. cgroups are a nasty interface, and letting knowledge of cgroups leak into the programs that live in the groups (as opposed to the cgroup manager) seems like a huge mistake to me. If you want to know where in the process hierarchy a message sender is, add *that* and figure out how to fix the races (it shouldn't be that hard). --Andy