How about this fix:
encode the kernel memory to only execute speculative command that are directly linked to the processor ID.Alternate is to use what we did on the KW7 cryptography equipment I used in Vietnam; whereas a direct signal was (phase tone in that equipment) was time dependent; along with unique data set, before transmission of data sets was initiated. This, along with the fact that the data was randomly encrypted made it impossible for interception of the communications unless the "spy" had physical presents in the communications channel and both the equipment encryption settings, and executed at the exact time of the "phase tone" link.
Note: This system was never penetrated by any security service. I am not a programmer, computer expert, or even had / have detailed technical knowledge of how the KW7 actually worked; but do know it was very effective in keeping communications secure.