From mboxrd@z Thu Jan 1 00:00:00 1970 From: aris-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org Subject: [PATCH 0/4] devcg: Store local settings for each device cgroup Date: Thu, 15 Aug 2013 11:34:10 -0400 Message-ID: <1376580854-30929-1-git-send-email-aris@redhat.com> Return-path: Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Li Zefan , Tejun Heo This patchset makes possible for device cgroups to store locally set rules to be reapplied whenever possible. This is also desired when moving device cgroups around. Consider: A / B Behavior in both is deny. 'A' has this exception list: b 1:* rw c *:* rw One can explicitely set on 'B': b 1:5 r If for some reason 'A' removes 'b 1:* rw', 'B' exception 'b 1:5 r' will be removed because it's not allowed anymore and would be forever lost. Now, consider that in the parent more fine grained exceptions were added: b 1:1 r b 1:2 rw b 1:4 rwc b 1:5 r B would still be out of exceptions (we only propagate restrictions, not added access). With this patchset, the 'b 1:5 r' exception will be kept and whenever possible (more specifically when the parent gets access to more devices) it'll be re-evaluated and applied if allowed. In this specific case, since it's allowed again, the exception 'b 1:5 r' will be reapplied to B. This patchset is based on for-3.12 branch on Tejun's tree (bd8815a6d802fc16a7a106e170593aa05dc17e72) and it's available for review on my git tree: git://github.com/aristeu/linux-2.6.git branch: devcg-rename Signed-off-by: Aristeu Rozanski