From mboxrd@z Thu Jan  1 00:00:00 1970
Subject: Re: JFFS2 deadlock with alloc_sem
From: David Woodhouse <dwmw2@infradead.org>
To: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
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Date: Mon, 30 Jul 2007 13:45:08 +0100
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Cc: linux-mtd@lists.infradead.org, ye janboe <janboe.ye@gmail.com>
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On Fri, 2007-07-27 at 12:38 -0500, Dave Kleikamp wrote:
> I could only speculate, since I really don't know the code.  I suspect
> the writer of the comment had some other deadlock scenario in mind and
> didn't foresee the one that was encountered. 

I'm still confused because we deliberately ensure the page is up to date
in prepare_write -- so read_cache_page() should never have to lock it,
and we should never deadlock.

Or did I miss something in your analysis (or elsewhere)?

Why is read_cache_page() ever trying to lock this page in the first
place? It should be up to date.

-- 
dwmw2