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Date: Thu, 22 May 2008 09:28:41 -0400
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [patch] remove xattr buffer size dependency on page size in
	xfsdump
Message-ID: <20080522132841.GD4972@infradead.org>
References: <20080522061402.GS173056135@sgi.com>
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To: David Chinner <dgc@sgi.com>
Cc: xfs-dev <xfs-dev@sgi.com>, xfs-oss <xfs@oss.sgi.com>

On Thu, May 22, 2008 at 04:14:02PM +1000, David Chinner wrote:
> 
> The extended attr buffer size used by xfsdump is based on page size.
> The maximum buffer size the kernel will accept is 64k. On a 64k page
> machine, the default buffer size will be rejected by the kernel, thereby
> breaking dump and restore.
> 
> Limit the buffer size to XATTR_LIST_MAX in dump, restore and libhandle
> so the kernel won't reject otherwise valid requests.

I suspect this will break on non-linux platforms because XATTR_LIST_MAX
is only in the Linux headers.  With a precaution, e.g. by keeping the
old behaviour when XATTR_LIST_MAX is not defined this looks good.