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Message-ID: <1361349910.10155.0.camel@laptop>
Subject: Re: [PATCH] Fix rq->lock vs logbuf_lock unlock race
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: "Bu, Yitian" <ybu@qti.qualcomm.com>
Cc: "tglx@linutronix.de" <tglx@linutronix.de>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "mingo@kernel.org" <mingo@kernel.org>
Date: Wed, 20 Feb 2013 09:45:10 +0100
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References: <E807E903FE6CBE4D95E420FBFCC273B827413C@nasanexd01h.na.qualcomm.com>
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On Mon, 2013-02-18 at 12:53 +0000, Bu, Yitian wrote:
> This patch is for kernel V3.7.9
> 
> From 8796f4a2175a323aaa49ea8dd0fe68678dd5dccd Mon Sep 17 00:00:00 2001
> From: ybu <ybu@qti.qualcomm.com>
> Date: Mon, 18 Feb 2013 19:52:01 +0800
> Subject: [PATCH] Fix rq->lock vs logbuf_lock unlock race
> 
> fix up the fallout from commit 07354eb1a74d1 ("locking printk:
> Annotate logbuf_lock as raw")
> Release console_sem after unlocking the logbuf_lock avoids some lock
> inversion troubles between logbuf_lock and rq->lock.

Please clarify how and where.. you're not actually supposed to use
printk() while holding rq->lock.