In fact, V2 tackles this issue at efi_init() for both arm64 and risc-v. Since in Zhen Lei's series "[PATCH v17 00/10] support reserving crashkernel above 4G on arm64 kdump", [8/10] is self-standing and meaningful. I abstract and utilize it. I make a small change in it in order to use early_init_dt_check_for_usable_mem_range() outside of/fdt. (Cc: Zhen, please let me know if it is not fine for you.) So finally these two patches can be applied as candidates for Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling") [1]: https://lore.kernel.org/all/20211210065533.2023-9-thunder.leizhen@xxxxxxxxxx/ v1 -> v2: Adopt Rob's suggestion to call early_init_dt_check_for_usable_mem_range() from efi_init() Cc: Rob Herring <robh+dt@xxxxxxxxxx> Cc: Zhen Lei <thunder.leizhen@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxx> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> Cc: Frank Rowand <frowand.list@xxxxxxxxx> Cc: Ard Biesheuvel <ardb@xxxxxxxxxx> Cc: Nick Terrell <terrelln@xxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx To: devicetree@xxxxxxxxxxxxxxx To: linux-efi@xxxxxxxxxxxxxxx Pingfan Liu (1): efi: apply memblock cap after memblock_add() Zhen Lei (1): of: fdt: Aggregate the processing of "linux,usable-memory-range" drivers/firmware/efi/efi-init.c | 7 +++++++ drivers/of/fdt.c | 18 +++++++++++++----- include/linux/of_fdt.h | 1 + 3 files changed, 21 insertions(+), 5 deletions(-) -- 2.31.1