linux-kernel - Re: [RFC][-mm] Add an owner to the mm

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

Message-ID: <47F1E3C1.6050802@linux.vnet.ibm.com>
Date:	Tue, 01 Apr 2008 12:56:57 +0530
From:	Balbir Singh <balbir@...ux.vnet.ibm.com>
To:	Paul Menage <menage@...gle.com>
CC:	Pavel Emelianov <xemul@...nvz.org>,
	Hugh Dickins <hugh@...itas.com>,
	Sudhir Kumar <skumar@...ux.vnet.ibm.com>,
	YAMAMOTO Takashi <yamamoto@...inux.co.jp>, lizf@...fujitsu.com,
	linux-kernel@...r.kernel.org, taka@...inux.co.jp,
	linux-mm@...ck.org, David Rientjes <rientjes@...gle.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
Subject: Re: [RFC][-mm] Add an owner to the mm_struct (v3)

Paul Menage wrote:
> On Mon, Mar 31, 2008 at 11:23 PM, Balbir Singh
> <balbir@...ux.vnet.ibm.com> wrote:
>>  > Here we'll want to call vm_cgroup_update_mm_owner(), to adjust the
>>  > accounting. (Or if in future we end up with more than a couple of
>>  > subsystems that want notification at this time, we'll want to call
>>  > cgroup_update_mm_owner() and have it call any interested subsystems.
>>  >
>>
>>  I don't think we need to adjust accounting, since only mm->owner is changing and
>>  not the cgroup to which the task/mm belongs. Do we really need to notify? I
>>  don't want to do any notifications under task_lock().
> 
> It's possible but unlikely that the new owner is in a different cgroup.

Hmmm... that can never happen with thread groups, since mm->owner is
p->group_leader and that never exits unless all threads are gone (it can
explicitly change groups though). Without thread groups, the new owner can
belong to a different cgroup, so we might need notification.


-- 
	Warm Regards,
	Balbir Singh
	Linux Technology Center
	IBM, ISTL
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/