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Date:	Sun, 5 Jul 2009 07:19:33 -0700 (PDT)
From:	Linus Torvalds <torvalds@linux-foundation.org>
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To:	Wu Zhangjin <wuzhangjin@gmail.com>
cc:	linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-mips@linux-mips.org, Krzysztof Helt <krzysztof.h1@wp.pl>,
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	=?GB2312?B?6sy7qg==?= <yanh@lemote.com>,
	zhangfx <zhangfx@lemote.com>
Subject: Re: [BUG] drivers/video/sis: deadlock introduced by "fbdev: add
 mutex for fb_mmap locking"
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On Sun, 5 Jul 2009, Wu Zhangjin wrote:
> 
> then it works! so, I guess there is a deadlock introduced by the above
> commit.

Hmm. Perhaps more likely, the 'mm_lock' mutex hasn't even been initialized 
yet.  We appear to have had that problem with matroxfb and sm501fb, and it 
may be more common than that. See commit f50bf2b2.

That said, I do agree that the mm_lock seems to be causing more problems 
than it actually fixes, and maybe we should revert it. Krzysztof?

		Linus