The loop which checks to see if "dynamic" IDT entries are allocated
needs to compare with the trampoline address of the reserved ISR.
Otherwise it will never succeed.
Reported by: Harry Schmalzbauer <freebsd@omnilan.de>
Tested by: Harry Schmalzbauer <freebsd@omnilan.de>
Reviewed by: kib
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D30576