From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Luck, Tony" <tony.luck@intel.com>
Date: Fri, 17 Oct 2003 22:19:49 +0000
Subject: RE: [RFC] prevent "dd if=/dev/mem" crash
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To: linux-ia64@vger.kernel.org

> I expect there are probably different opinions about the idea
> that "dd if=/dev/mem" exits without doing anything.  Sparc and
> 68K have nearby code that bit-buckets writes and returns zeroes
> for reads of page zero.  We could do that, too, but it seems like
> kind of a hack, and holes on ia64 can be BIG (on the order of
> 256GB for one box).

Filling in the holes does seem like a bad idea, but so does returning
EOF when you hit a hole (which is what I think your patch is doing).

Would ENODEV be better?

-Tony