[RFC PATCH 09/12] PAT 64b: map only usable memory in identity mapping

Map only the usable memory, i.e., memory mapped in e820 and not marked as reserved, in the identity mapping. This includes 'usable' and 'ACPI *' regions. Mapping reserved regions in identity map, even though it has worked in practise, can potentially be problematic. With identity map, there can

[RFC PATCH 09/12] PAT 64b: map only usable memory in identity mapping

Map only the usable memory, i.e., memory mapped in e820 and not marked as reserved, in the identity mapping. This includes 'usable' and 'ACPI *' regions. Mapping reserved regions in identity map, even though it has worked in practise, can potentially be problematic. With identity map, there can