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Subject: Re: sched/core: WARNING in __might_sleep
From: Johannes Berg <johannes@sipsolutions.net>
To: Peter Zijlstra <peterz@infradead.org>, Baozeng <sploving1@gmail.com>
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Date: Mon, 01 Feb 2016 12:26:06 +0100
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On Mon, 2016-02-01 at 12:13 +0100, Peter Zijlstra wrote:
> 
> Yeah, from the rfkill code, which you failed to CC.

Thanks Peter :)

> In any case, this is a fail in the rfkill code, which should be
> sorted
> with the below patch (but the rfkill people should double check), and
> ideally they'd use list_empty_careful() instead of the mutex, but I
> don't know their code well enough to say if that's safe or not.

Even list_empty() is fine in this case since we go and recheck it
anyway in the calling loop, while the mutex is held.

I have commit 6736fde9672f on its way to mainline.

johannes