From: Ma Wupeng <mawupeng1@xxxxxxxxxx> Commit b05b9f5f9dcf ("x86, mirror: x86 enabling - find mirrored memory ranges") introduced mirrored memory support for x86. This support rely on UEFI to report mirrored memory address ranges. See UEFI 2.5 spec pages 157-158: http://www.uefi.org/sites/default/files/resources/UEFI%202_5.pdf Memory mirroring is a technique used to separate memory into two separate channels, usually on a memory device, like a server. In memory mirroring, one channel is copied to another to create redundancy. This method makes input/output (I/O) registers and memory appear with more than one address range because the same physical byte is accessible at more than one address. Using memory mirroring, higher memory reliability and a higher level of memory consolidation are possible. Arm64 can support this too. So mirrored memory support is added to support arm64. Efi_fake_mem is used for testing mirrored features and will not be used in production environment. This test features can fake memory's attribute values. The reason why efi_fake_mem support is put first is that memory's attribute is reported by BIOS which is hard to simulate. With this support, any arm64 machines with efi support can easily test mirrored features. The main purpose of this patchset is to introduce mirrored support for arm64 and we have already fixed the problems we had which is shown in patch #5 to patch #7 and try to bring total isolation in patch #8 which will disable mirror feature if kernelcore is not specified. In order to test this support in arm64: - patch this patchset - add efi_fake_mem=8G@0:0x10000 in kernel parameter to simulate mirrored memroy between phy addr 0-8G. - add kernelcore=mirror in kernel parameter - start you kernel Patch #1-#2 introduce efi_fake_mem support for arm64. Patch #3-#4 introduce mirrored memory support form arm64. Patch #5-#7 fix some bugs for arm64 if memory reliable is enabled. Patch #8 disable mirror feature if kernelPHYS_PFNcore is not specified. Patch #9 remove some redundant code in ia64 efi_init. Changelog since v1: - update changelog in cover letter - use PHYS_PFN in patch #7 Ma Wupeng (9): efi: Make efi_print_memmap() public arm64: efi: Add fake memory support efi: Make efi_find_mirror() public arm64/mirror: arm64 enabling - find mirrored memory ranges mm: Ratelimited mirrored memory related warning messages mm: Demote warning message in vmemmap_verify() to debug level mm: Calc the right pfn if page size is not 4K efi: Disable mirror feature if kernelcore is not specified ia64/efi: Code simplification in efi_init .../admin-guide/kernel-parameters.txt | 4 +- arch/arm64/kernel/setup.c | 3 ++ arch/ia64/kernel/efi.c | 37 +----------------- arch/x86/include/asm/efi.h | 5 --- arch/x86/platform/efi/efi.c | 39 ------------------- drivers/firmware/efi/Kconfig | 2 +- drivers/firmware/efi/efi.c | 26 +++++++++++++ drivers/firmware/efi/memmap.c | 16 ++++++++ include/linux/efi.h | 4 ++ include/linux/mm.h | 2 + mm/memblock.c | 4 +- mm/page_alloc.c | 4 +- mm/sparse-vmemmap.c | 2 +- 13 files changed, 60 insertions(+), 88 deletions(-) -- 2.18.0.huawei.25