linux/drivers/s390
Mike Snitzer b277da0a8a block: disable entropy contributions for nonrot devices
Clear QUEUE_FLAG_ADD_RANDOM in all block drivers that set
QUEUE_FLAG_NONROT.

Historically, all block devices have automatically made entropy
contributions.  But as previously stated in commit e2e1a148 ("block: add
sysfs knob for turning off disk entropy contributions"):
    - On SSD disks, the completion times aren't as random as they
      are for rotational drives. So it's questionable whether they
      should contribute to the random pool in the first place.
    - Calling add_disk_randomness() has a lot of overhead.

There are more reliable sources for randomness than non-rotational block
devices.  From a security perspective it is better to err on the side of
caution than to allow entropy contributions from unreliable "random"
sources.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-10-04 10:55:32 -06:00
..
block block: disable entropy contributions for nonrot devices 2014-10-04 10:55:32 -06:00
char s390/3215: fix hanging console issue 2014-07-28 10:02:39 +02:00
cio s390/qdio: add helpers to manage qdio buffers 2014-07-22 09:26:13 +02:00
crypto s390/zcrypt: improve device probing for zcrypt adapter cards 2014-07-16 10:48:12 +02:00
kvm virtio_ccw: introduce device_lost in virtio_ccw_device 2014-04-28 11:34:13 +09:30
net Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2014-08-07 08:41:00 -07:00
scsi Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2014-08-07 08:41:00 -07:00
Makefile