Date: Tue, 20 Aug 2013 08:22:00 -0400
From: Tejun Heo <tj@kernel.org>
To: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Pavel Machek <pavel@ucw.cz>, linux-pm@vger.kernel.org,
        Kyungmin Park <kyungmin.park@samsung.com>,
        LKML <linux-kernel@vger.kernel.org>, Colin Cross <ccross@android.com>
Subject: Re: [RFC PATCH] freezer: allow killing of frozen tasks
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On Tue, Aug 20, 2013 at 02:30:18PM +0200, Rafael J. Wysocki wrote:
> > So, I don't think we can simply turn TASK_UNITERRUPTIBLE to
> > TASK_KILLABLE at this point.  We really need to strictly define where
> > a task can freeze before being able to do anything like this.
> 
> But we could do that for user space tasks I suppose?

Even for userland tasks, we don't know where the task is stuck at.  I
think there are enough freeze points in the kernel which are in the
middle of something which can be used by userland tasks excuting some
syscall.  We need to collect all those sites into well defined trap
points before doing this.

Thanks.

-- 
tejun
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