It may happen on some machines, that even if SGX is disabled
in firmware, the driver would still attach despite EPC base and
size equal zero. Such behaviour causes a kernel panic when the
module is unloaded. Add a simple check to make sure we
only attach when these values are correctly set.
Submitted by: Kornel Duleba <mindal@semihalf.com>
Reviewed by: br
Obtained from: Semihalf
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D19595
3caad0b8f4