random: mix in architectural randomness in extract_buf()
authorH. Peter Anvin <hpa@linux.intel.com>
Sat, 28 Jul 2012 02:26:08 +0000 (22:26 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 15 Aug 2012 15:10:30 +0000 (08:10 -0700)
commit7d696f0636c31f81d5cb613d45114d43896cfdb0
tree60e3ff4fac431841c4752c59a39cb38b66d743b7
parentaf2eb889f75b4206de39ea86f4f154498a9327f3
random: mix in architectural randomness in extract_buf()

commit d2e7c96af1e54b507ae2a6a7dd2baf588417a7e5 upstream.

Mix in any architectural randomness in extract_buf() instead of
xfer_secondary_buf().  This allows us to mix in more architectural
randomness, and it also makes xfer_secondary_buf() faster, moving a
tiny bit of additional CPU overhead to process which is extracting the
randomness.

[ Commit description modified by tytso to remove an extended
  advertisement for the RDRAND instruction. ]

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: DJ Johnston <dj.johnston@intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/char/random.c