Originally Posted by R. Belmont
For the case where you need to restart instructions from an external MMU, m68k execute_run() needs a separate flag m_has_instruction_restart which all of the MMU configurations set and which is also settable externally so it can be enabled for 68010 systems with external MMUs.

Yes, this sounds just like what is needed. And then presumably the equivalent of m_mmu_tmp_buserror_occurred from m68k execute_run() being set in m68k_cause_bus_error().