From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Nelson Elhage <nelhage@ksplice.com>
Cc: Paul Menage <menage@google.com>, Li Zefan <lizf@cn.fujitsu.com>,
linux-kernel@vger.kernel.org
Subject: Re: cgroup scheduling: Adding kthreadd to a non-RT cgroup can deadlock the kernel
Date: Wed, 05 Jan 2011 16:18:30 +0100 [thread overview]
Message-ID: <1294240710.2016.264.camel@laptop> (raw)
In-Reply-To: <AANLkTi=FC27TTngERgbS95Z29CYBqLGxR4Uuw9fSTVuO@mail.gmail.com>
On Wed, 2011-01-05 at 10:02 -0500, Nelson Elhage wrote:
> Ok. I bothered reporting this here since the kernel /does/ try to prevent you
> from shooting yourself in the foot in related ways, by moving existing
> SCHED_FIFO tasks into a cgroup without any RT runtime, so I figured it might
> make sense to add a check here. libcgroup, for example, will try to move all
> processes into a default cgroup, ignoring errors, and relies on the kernel to
> prevent it from shooting itself in the foot.
>
> It sounds like you consider that behavior a bug, though, so I'll go report this
> bug there.
Right, so we try to catch obvious cases, but its near impossible to
catch all cases.
And its not only the scheduler controller, I bet you can get into
trouble with some of the other controllers as well.
prev parent reply other threads:[~2011-01-05 15:18 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-01-05 4:54 cgroup scheduling: Adding kthreadd to a non-RT cgroup can deadlock the kernel Nelson Elhage
2011-01-05 6:01 ` Mike Galbraith
2011-01-05 9:44 ` Peter Zijlstra
2011-01-05 15:02 ` Nelson Elhage
2011-01-05 15:18 ` Peter Zijlstra [this message]
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