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From: David Woodhouse <dwmw2@infradead.org>
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To: Vojtech Pavlik <vojtech@suse.cz>
Cc: Russell King <rmk@arm.linux.org.uk>, linux-kernel@vger.kernel.org,
       linuxconsole-dev@lists.sourceforge.net
Subject: Re: [patch] Fix suspend of the kseriod thread 
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vojtech@suse.cz said:
>  Ok. Is the use in drivers/input/serio.c buggy? 

If it matters that the thread can miss wakeup events and sleep indefinitely 
while there's a 'SERIO_RESCAN' event pending, then yes it looks buggy.

	serio_thread()				serio_rescan()
	--------------				--------------

	serio_handle_events();
						serio->event |= SERIO_RESCAN;
						wake_up(&serio_wait);
	sleep_on(&serio_wait);

	...sleeps...

If both serio_thread() and serio_rescan() hold the BKL you're OK. It looks 
like serio_rescan() doesn't, though.

> What should be it replaced with?

In general, the response 'anything but sleep_on' is considered appropriate.
Try wait_event().

--
dwmw2


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