Handle previous allocation failures when freeing device memory
Signed-off-by: NSimon Graham <simon.graham@virtualcomputer.com>
Signed-off-by: NLarry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>