From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthew Wilcox <matthew@wil.cx>
Subject: Re: Is a NULL check missing in nfs_lookup?
Date: Fri, 5 Jan 2007 12:23:04 -0700
Message-ID: <20070105192304.GH24620@parisc-linux.org>
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Cc: Trond Myklebust <trond.myklebust@fys.uio.no>,
	Chaitanya Patti <crpatti@cs.sunysb.edu>,
	linux-fsdevel@vger.kernel.org
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To: Erez Zadok <ezk@cs.sunysb.edu>
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On Fri, Jan 05, 2007 at 02:10:06PM -0500, Erez Zadok wrote:
> Ah, ok.  So why not put an ASSERT in there, or at least a comment, to make
> the code clearer.  As it stands, anyone looking at the code in the future
> can easily rediscover this "bug" that dereferences a null ptr.

Because anyone poking in the VFS should take the time to understand
how it works?  Adding crap like BUG_ON(!nd) is pointless -- you don't
get a clearer backtrace from that than you do from a null pointer.