After upgrading from RELEASE 11.1-p7 to RELEASE 11.1-p8, a new feature appears, called hw.ibrs_active
This feature, when activated, is dangerous: it will crash the system at the next time a suspend-to-RAM is performed (reboot without dump).
This works as well the other way: if the system has ever been suspended-to-RAM beforehand, then activating this feature will as well perform a system crash (CPU crash without dump).
The behaviour is a little bit erratic: on some occasion, "acpiconf -s 3" will just become a no-op, on other occasion the hw.ibrs_active will not activate, on other occasion the system will render unbootable (and require a full disconnect primary), and in any case you will have some fun...
(As this stuff seems to be CPU-related: here it is i5-3570T)
This feature, when activated, is dangerous: it will crash the system at the next time a suspend-to-RAM is performed (reboot without dump).
This works as well the other way: if the system has ever been suspended-to-RAM beforehand, then activating this feature will as well perform a system crash (CPU crash without dump).
The behaviour is a little bit erratic: on some occasion, "acpiconf -s 3" will just become a no-op, on other occasion the hw.ibrs_active will not activate, on other occasion the system will render unbootable (and require a full disconnect primary), and in any case you will have some fun...
(As this stuff seems to be CPU-related: here it is i5-3570T)