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The legacy 32-bit SMBIOS entry point has little use on AARCH64 systems, since many such systems have no 32-bit addressable physical RAM, and so OSes that implement SMBIOS will have to be able to deal with the 64-bit entry point anyway. Given that the OS will map main memory in 1 GB chunks if it can, and that punching a page sized hole (e.g., for SMBIOS data) into it will result in the whole 1 GB chunk being mapped using 2 MB and 4 KB blocks instead, it is important to group memory reservations from the OS as much as we can, and allocating below 4 GB for no good reason interferes with that. This is especially important under virtualization, considering that each *level* of lookup at stage 1 (the guest virtual page table) will result in a full page table walk at stage 2 (the guest PA to host PA mapping). So expose only the 64-bit entry point when the SMBIOS tables adhere to version 3.0 or later. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Laszlo Ersek <lersek@redhat.com>