At the time of writing SMM runtime does not make register accesses to LAPIC registers, but such breakage has been reported. S3 resume failure, where OS switched back from X2APIC to XAPIC mode, can be reproduced with a sandybridge SKU that has VT-d disabled. Change-Id: I300ba87c3d8fde548dbaf95703bd7e2fe54cff57 Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/76196 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Elyes Haouas <ehaouas@noos.fr>