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Date: Fri, 23 May 2008 23:52:20 +0200 (CEST)
From: Roman Zippel <zippel@linux-m68k.org>
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To: Miklos Szeredi <miklos@szeredi.hu>
cc: hch@infradead.org, linux-fsdevel@vger.kernel.org, viro@ZenIV.linux.org.uk,
       linux-kernel@vger.kernel.org
Subject: Re: [patch 06/14] hfsplus: remove hfsplus_permission()
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Hi,

On Fri, 23 May 2008, Miklos Szeredi wrote:

> Semi-concrete: link(2) locks the target's parent and the source.
> Cross-directory rename(2) locks both parents.  If link's target is a
> file which has children, this can result in an ABBA deadlock.  That's
> _before_ the filesystem's ->link() or ->rename() function is called.

I'm afraid you have to be more concrete than this. 
hfsplus_file_inode_operations doesn't have a link or rename operation, so 
if one your source parents above involves a file, it shouldn't get this 
far or you have to describe your scenario in more detail.

bye, Roman