From: "Jack O'Quin" <joq@io.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>,
Paul Davis <paul@linuxaudiosystems.com>,
Con Kolivas <kernel@kolivas.org>,
linux <linux-kernel@vger.kernel.org>,
rlrevell@joe-job.com, CK Kernel <ck@vds.kolivas.org>,
utz <utz@s2y4n2c.de>, Andrew Morton <akpm@osdl.org>,
alexn@dsv.su.se, Rui Nuno Capela <rncbc@rncbc.org>,
Chris Wright <chrisw@osdl.org>,
Arjan van de Ven <arjanv@redhat.com>
Subject: Re: [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU_RATIO feature
Date: Fri, 28 Jan 2005 02:35:30 -0600 [thread overview]
Message-ID: <871xc62bot.fsf@sulphur.joq.us> (raw)
In-Reply-To: <20050128080802.GA2860@elte.hu> (Ingo Molnar's message of "Fri, 28 Jan 2005 09:08:02 +0100")
Ingo Molnar <mingo@elte.hu> writes:
> * Nick Piggin <nickpiggin@yahoo.com.au> wrote:
>
>> And finally, with rlimit support, is there any reason why lockup
>> detection and correction can't go into userspace? Even RT throttling
>> could probably be done in a userspace daemon.
>
> that is correct. Jackd already has a watchdog thread, against lockups.
>
> i'm wondering, couldnt Jackd solve this whole issue completely in
> user-space, via a simple setuid-root wrapper app that does nothing else
> but validates whether the user is in the 'jackd' group and then keeps a
> pipe open to to the real jackd process which it forks off, deprivileges
> and exec()s? Then unprivileged jackd could request RT-priority changes
> via that pipe in a straightforward way. Jack normally gets installed as
> root/admin anyway, so it's not like this couldnt be done.
Perhaps.
Until recently, that didn't work because of the longstanding rlimits
bug in mlockall(). For scheduling only, it might be possible.
Of course, this violates your requirement that the user not be able to
lock up the CPU for DoS. The jackd watchdog is not perfect.
--
joq
next prev parent reply other threads:[~2005-01-28 8:34 UTC|newest]
Thread overview: 198+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-01-19 22:39 [PATCH]sched: Isochronous class v2 for unprivileged soft rt scheduling Con Kolivas
2005-01-20 0:16 ` utz lehmann
2005-01-20 0:33 ` Con Kolivas
2005-01-20 4:26 ` utz lehmann
2005-01-20 5:55 ` Con Kolivas
2005-01-20 17:54 ` Alexander Nyberg
2005-01-20 20:27 ` Con Kolivas
2005-01-20 0:53 ` Con Kolivas
2005-01-20 1:32 ` Jack O'Quin
2005-01-20 2:06 ` Con Kolivas
2005-01-20 2:45 ` Jack O'Quin
2005-01-20 4:07 ` Con Kolivas
2005-01-20 4:57 ` Jack O'Quin
2005-01-20 5:05 ` Gene Heskett
2005-01-20 5:59 ` Con Kolivas
2005-01-20 6:35 ` Con Kolivas
2005-01-20 15:19 ` Jack O'Quin
2005-01-20 15:42 ` Paul Davis
2005-01-20 16:47 ` Jack O'Quin
2005-01-20 17:25 ` Ingo Molnar
2005-01-22 0:09 ` Jack O'Quin
2005-01-22 16:54 ` Ingo Molnar
2005-01-22 21:23 ` Jack O'Quin
2005-01-23 2:06 ` Nick Piggin
2005-01-23 2:58 ` Chris Wright
2005-01-24 8:59 ` Ingo Molnar
2005-01-24 9:55 ` Paolo Ciarrocchi
2005-01-24 10:29 ` Nick Piggin
2005-01-24 10:46 ` Ingo Molnar
2005-01-24 12:58 ` [patch, 2.6.11-rc2] sched: /proc/sys/kernel/rt_cpu_limit tunable Ingo Molnar
2005-01-24 13:34 ` Ingo Molnar
2005-01-24 13:53 ` Con Kolivas
2005-01-24 14:01 ` [ck] " Con Kolivas
[not found] ` <87k6q2umla.fsf@sulphur.joq.us>
2005-01-25 6:28 ` Nick Piggin
2005-01-25 14:12 ` Ingo Molnar
2005-01-25 8:37 ` Ingo Molnar
2005-01-25 21:36 ` Jack O'Quin
2005-01-25 21:49 ` Ingo Molnar
2005-01-25 21:55 ` Chris Wright
2005-01-25 21:57 ` Ingo Molnar
2005-01-25 22:03 ` Chris Wright
2005-01-25 22:08 ` Ingo Molnar
2005-01-25 22:16 ` Chris Wright
2005-01-25 22:44 ` Bill Rugolsky Jr.
2005-01-26 5:12 ` Jack O'Quin
2005-01-26 7:27 ` Ingo Molnar
2005-01-26 11:02 ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU feature, -D7 Ingo Molnar
2005-01-25 13:56 ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU_RATIO feature Ingo Molnar
2005-01-25 14:06 ` Con Kolivas
2005-01-25 22:18 ` Peter Williams
2005-01-25 22:26 ` Peter Williams
2005-01-26 10:08 ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU feature, -D7 Ingo Molnar
2005-01-26 14:22 ` Jack O'Quin
2005-01-26 16:18 ` [ck] " Cal
2005-01-26 16:29 ` Cal
2005-01-26 16:41 ` Jack O'Quin
2005-01-26 17:57 ` Cal
2005-01-26 18:57 ` Jack O'Quin
2005-01-27 2:03 ` Cal
2005-01-27 8:51 ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU feature, -D8 Ingo Molnar
2005-01-27 12:48 ` Cal
2005-01-27 16:31 ` Mike Galbraith
2005-01-26 21:28 ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU feature, -D7 Peter Williams
2005-01-26 21:44 ` Peter Williams
2005-01-26 9:20 ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU_RATIO feature Ingo Molnar
2005-01-31 23:03 ` Peter Williams
2005-02-01 10:11 ` [patch] sys_setpriority() euid semantics fix Ingo Molnar
2005-02-01 21:46 ` Peter Williams
2005-01-26 5:24 ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU_RATIO feature Jack O'Quin
2005-01-26 7:04 ` Ingo Molnar
2005-01-26 22:27 ` Jack O'Quin
2005-01-26 23:29 ` Nick Piggin
2005-01-27 2:31 ` Jack O'Quin
2005-01-27 3:26 ` Nick Piggin
2005-01-27 5:15 ` Jack O'Quin
2005-01-27 5:54 ` Nick Piggin
2005-01-27 8:35 ` Ingo Molnar
2005-01-27 8:59 ` Ingo Molnar
2005-01-27 11:35 ` Ingo Molnar
2005-02-02 5:10 ` Jack O'Quin
2005-02-02 11:10 ` Bill Huey
2005-02-02 16:44 ` Jack O'Quin
2005-02-02 21:14 ` Bill Huey
2005-02-02 21:20 ` Bill Huey
2005-02-02 21:21 ` Ingo Molnar
2005-02-02 21:34 ` Bill Huey
2005-02-02 22:59 ` Paul Davis
2005-02-03 2:46 ` Bill Huey
2005-02-03 14:20 ` Paul Davis
2005-02-03 20:19 ` Con Kolivas
2005-02-03 20:47 ` Ingo Molnar
2005-02-03 21:15 ` Paul Davis
2005-02-03 21:28 ` Ingo Molnar
2005-02-03 21:41 ` Paul Davis
2005-02-03 21:59 ` Ingo Molnar
2005-02-03 22:24 ` Paul Davis
2005-02-03 22:26 ` Ingo Molnar
2005-02-04 0:36 ` Tristan Wibberley
2005-02-03 21:48 ` Peter Williams
2005-02-04 16:41 ` Jack O'Quin
2005-02-04 21:38 ` Peter Williams
2005-02-03 21:41 ` Ingo Molnar
2005-02-03 23:01 ` Bill Huey
2005-02-11 21:27 ` Lee Revell
2005-02-02 21:54 ` Peter Williams
2005-02-02 23:03 ` Paul Davis
2005-02-02 23:46 ` Peter Williams
2005-02-03 1:13 ` Jack O'Quin
2005-02-03 3:10 ` Peter Williams
2005-02-03 3:56 ` Jack O'Quin
2005-02-03 21:36 ` Ingo Molnar
2005-02-04 0:35 ` Chris Wright
2005-02-04 17:21 ` Jack O'Quin
2005-02-03 2:54 ` Bill Huey
2005-02-03 3:25 ` Peter Williams
2005-02-02 11:37 ` Ingo Molnar
2005-02-02 16:01 ` Jack O'Quin
2005-02-02 18:59 ` Lee Revell
2005-02-02 19:31 ` Jack O'Quin
2005-02-02 20:29 ` Ingo Molnar
2005-02-02 22:45 ` Jack O'Quin
2005-02-02 20:17 ` Ingo Molnar
2005-01-27 20:01 ` Lee Revell
2005-01-28 6:38 ` Ingo Molnar
2005-01-28 8:09 ` Jack O'Quin
2005-01-28 8:08 ` Ingo Molnar
2005-01-28 8:35 ` Jack O'Quin [this message]
2005-01-28 8:40 ` Ingo Molnar
2005-01-28 9:01 ` Jack O'Quin
2005-01-28 9:11 ` Ingo Molnar
2005-01-29 0:44 ` Lee Revell
2005-01-28 9:51 ` Mike Galbraith
2005-01-28 22:16 ` Peter Williams
2005-01-28 22:19 ` Ingo Molnar
2005-01-29 7:02 ` Jack O'Quin
2005-01-31 22:29 ` Bill Davidsen
2005-02-01 0:39 ` Bill Huey
2005-01-25 5:16 ` [PATCH]sched: Isochronous class v2 for unprivileged soft rt scheduling Jack O'Quin
2005-01-25 15:09 ` Ingo Molnar
2005-01-23 20:48 ` Jack O'Quin
2005-01-23 22:57 ` Con Kolivas
2005-01-24 1:06 ` Jack O'Quin
2005-01-24 1:09 ` Con Kolivas
2005-01-24 4:45 ` Jack O'Quin
2005-01-24 4:53 ` Jack O'Quin
2005-01-24 6:28 ` Jack O'Quin
2005-01-24 6:35 ` Con Kolivas
2005-01-24 6:57 ` Jack O'Quin
2005-01-24 22:58 ` Con Kolivas
2005-01-25 3:55 ` Con Kolivas
2005-01-25 13:05 ` Con Kolivas
2005-01-25 14:38 ` Con Kolivas
2005-01-25 18:36 ` Jack O'Quin
2005-01-25 20:52 ` Rui Nuno Capela
2005-01-24 21:46 ` Con Kolivas
2005-01-23 7:38 ` Jack O'Quin
2005-01-23 7:41 ` Con Kolivas
2005-01-24 6:30 ` Jack O'Quin
2005-01-24 20:55 ` Ingo Molnar
2005-01-20 21:59 ` Peter Chubb
2005-01-21 0:30 ` Jack O'Quin
2005-01-22 14:06 ` Paul Davis
2005-01-20 17:49 ` ross
2005-01-20 19:07 ` Lee Revell
2005-01-20 23:17 ` Con Kolivas
2005-01-21 7:48 ` Ingo Molnar
2005-02-07 3:09 ` Werner Almesberger
2005-02-07 3:27 ` Jack O'Quin
2005-02-07 3:27 ` Con Kolivas
2005-01-20 9:06 ` Rui Nuno Capela
2005-01-20 17:09 ` Rui Nuno Capela
2005-01-20 19:32 ` Jack O'Quin
2005-01-21 9:18 ` Rui Nuno Capela
2005-01-21 16:23 ` Con Kolivas
2005-01-21 16:40 ` Jack O'Quin
2005-01-22 0:06 ` Con Kolivas
2005-01-22 6:18 ` Jack O'Quin
2005-01-22 6:19 ` Con Kolivas
2005-01-22 6:48 ` Con Kolivas
2005-01-22 6:50 ` Con Kolivas
2005-01-22 7:09 ` Con Kolivas
2005-01-22 20:22 ` Jack O'Quin
2005-01-23 1:02 ` Con Kolivas
2005-01-23 3:02 ` Jack O'Quin
2005-01-23 4:29 ` Con Kolivas
2005-01-23 4:46 ` Jack O'Quin
2005-01-23 4:50 ` Con Kolivas
2005-01-23 7:37 ` Mike Galbraith
2005-01-23 13:57 ` Paul Davis
2005-01-23 1:31 ` Con Kolivas
2005-01-23 1:41 ` Paul Davis
2005-01-23 1:56 ` Con Kolivas
2005-01-23 4:50 ` Jack O'Quin
2005-01-21 23:30 ` utz lehmann
2005-01-21 23:48 ` Con Kolivas
2005-01-22 0:28 ` utz lehmann
2005-01-22 3:52 ` Con Kolivas
2005-01-22 6:15 ` Jack O'Quin
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