Facilitating execution of mmio based instructions

A computer system comprising:

• a memory;
• a host CPU, coupled to the memory;
• and
• a hypervisor hosted by the computer system, having access to the memory and use of the host CPU, the hypervisor to:
• receive an indication of an exit by a guest to the hypervisor and a memory-mapped input output (MMIO) address that caused the exit to hypervisor;
• walk a page table of the guest to identify a guest address associated with the MMIO address that caused the exit to the hypervisor;
• decode an instruction of the guest referenced by the guest address to determine a type of operation that the guest intended to execute and a location of MMIO information;
• record, in a page table entry for the MMIO address of a host page table, an association with the type of operation and the location of the MMIO information;
• and
• execute the operation on behalf of the guest based on the type of the operation and the MMIO information.

A non-transitory computer-readable storage medium including instructions that, when accessed by a processing system, cause the processing system to perform operations comprising:

• receiving, by a hypervisor of a host, an indication of an exit by a guest to the hypervisor and a memory-mapped input output (MMIO) address that caused the exit to hypervisor;
• walking, by the hypervisor, a page table of the guest to identify a guest address associated with the MMIO address that caused the exit to the hypervisor;
• decoding, by the hypervisor, an instruction of the guest referenced by the guest address to determine a type of operation that the guest intended to execute and a location of MMIO information;
• recording, by the hypervisor in a page table entry for the MMIO address of a host page table, an association with the type of operation and the location of the MMIO information;
• and
• executing, by the hypervisor, the operation on behalf of the guest based on the type of the operation and the MMIO information.