Hi Linus,

On Thu, 5 Sep 2013, Linus Walleij wrote:

Atleast eight bytes of this number are totally unique for the device
it seems, so this is a perfect candidate for feeding the entropy
pool. One byte more or less of constants does not matter so feed in
the entire OID struct.

Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Paul Walmsley <paul@pwsan.com>
Reviewed-by: Kevin Hilman <redacted>
Signed-off-by: Linus Walleij <redacted>

Heh, that function name "add_device_randomness()" is a bit misleading.  
It's not actually intended to add "randomness": from 
drivers/char/random.c:

/*
 * Add device- or boot-specific data to the input and nonblocking
 * pools to help initialize them to unique values.
 *
 * None of this adds any entropy, it is meant to avoid the
 * problem of the nonblocking pool having similar initial state
 * across largely identical devices.
 */

But of course the function name is not your fault :-)  The entropy count 
isn't increased by this, so:

Reviewed-by: Paul Walmsley <paul@pwsan.com>

Thanks Linus.


- Paul