On Wed, Jan 10, 2024 at 04:05:44PM +0800, Dun Tan wrote: > When creating smm page table, limit maximum > supported physical address bits returned by > CalculateMaximumSupportAddress() to 48 if > 5-Level Paging is disabled. > When 5-Level Paging is disabled and the > PhysicalAddressBits retrived from CPU HOB or > CpuId is bigger than 48, only [0, 2^48 -1] > range in 52-bit physical address is mapped > in page table.
I think this is wrong. Virtual addresses are sign-extended, i.e. the virtual address space without 5-level paging is: 0x0000000000000000 -> 0x00007fffffffffff and 0xffff800000000000 -> 0xffffffffffffffff Therefore identity-mapping works for [0, 2^47-1] only. take care, Gerd -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#113523): https://edk2.groups.io/g/devel/message/113523 Mute This Topic: https://groups.io/mt/103637402/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
