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Date: Fri, 28 Jul 2006 21:34:46 -0400
From: Benjamin LaHaise <bcrl@kvack.org>
To: Zach Brown <zach.brown@oracle.com>
Cc: linux-kernel@vger.kernel.org, linux-aio@kvack.org,
       Arjan van de Ven <arjan@infradead.org>
Subject: Re: [RFC][PATCH] Fix lock inversion aio_kick_handler()
Message-ID: <20060729013446.GA3387@kvack.org>
References: <20060729001032.GA7885@tetsuo.zabbo.net>
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On Fri, Jul 28, 2006 at 05:10:32PM -0700, Zach Brown wrote:
> Fix lock inversion aio_kick_handler()

Doh.  Unfortunately, this patch isn't entirely correct as it could race with 
__put_ioctx() which sets ioctx->mm = NULL.  Something like the following 
should do the trick:

	struct mm_struct *mm;
...
> - 	unuse_mm(ctx->mm);
+	mm = ctx->mm;
>  	spin_unlock_irq(&ctx->ctx_lock);
+ 	unuse_mm(mm);
>  	set_fs(oldfs);
>  	/*
...


		-ben
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