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Subject: Re: [patch 1/4] ps3fb: thread updates
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Christoph Hellwig <hch@lst.de>
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Date: Fri, 16 Feb 2007 08:43:37 +1100
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Cc: Geert.Uytterhoeven@sonycom.com, linuxppc-dev@ozlabs.org,
	Andrew Morton <akpm@linux-foundation.org>,
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On Thu, 2007-02-15 at 18:50 +0100, Christoph Hellwig wrote:
> On Thu, Feb 15, 2007 at 04:23:02PM +0100, Geert.Uytterhoeven@sonycom.com wrote:
> > +	do {
> > +		try_to_freeze();
> > +		error = down_interruptible(&ps3fb.sem);
> > +		if (!error && !atomic_read(&ps3fb.ext_flip))
> >  			ps3fb_sync(0);	/* single buffer */
> 
> this still can deadlock when calling kthread_stop.  You really want
> to use wake_up_process to kick this thread or use a workqueue.

kthread_stop does wake_up_process no ? However, that might not get you
out of interruptible if you don't also have signal_pending...

Ben.