Re: [RFC] prevent "dd if=/dev/mem" crash

Andreas Schwab
2003-10-17T22:40:48Z

"Luck, Tony" <tony.luck@intel.com> writes:

>> 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?

EIO would probably fit better.

Andreas.

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