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Date: Wed, 7 Jan 2015 16:37:17 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Cc: <ionut.m.alexa@gmail.com>, <mark.yang@spreadtrum.com>,
        <wei.qiao@spreadtrum.com>, <geng.ren@spreadtrum.com>,
        <orson.zhai@spreadtrum.com>, <zhizhou.zhang@spreadtrum.com>,
        <ke.wang@spreadtrum.com>, <zhang.lyra@gmail.com>,
        <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] kernel: async: Fixed the wrong waitting condition of
 wait_event
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References: <async>
	<1420428935-30385-1-git-send-email-chunyan.zhang@spreadtrum.com>
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On Mon, 5 Jan 2015 11:35:35 +0800 Chunyan Zhang <chunyan.zhang@spreadtrum.com> wrote:

> This patch changes the waitting condition of wait_event in the
> function 'async_synchronize_cookie_domain'.
> 
> This function waits until all asynchronous function calls for the certain
> domain have been done.
> 
> But, the function 'lowest_in_progress' returns the lowest *pending*
> entry's cookie.
> 
> So we should make sure that the return value of lowest_in_progress(domain)
> must be larger than @cookie.

I'm having runtime problems with this.  Twice the kernel silently hangs
late in initcalls and the third time I got a great stream of oopses.

I'll drop it.  Hopefully you'll be able to work through the bug with
Arjan and Tajun.