Hi all, This patch series adds generic support for parsing DT properties related to crash dump kernels ("linux,elfcorehdr" and "linux,elfcorehdr" under the "/chosen" node), makes use of it on arm32, and performs a few cleanups. It is an evolution of the combination of [1] and [2]. The series consists of 6 parts: 1. Patch 1 prepares architecture-specific code (needed for MIPS only) to avoid duplicating elf core header reservation later. 2. Patch 2 prepares the visibility of variables used to hold information retrieved from the DT properties. 3. Patches 3-5 add support to the FDT core for handling the properties. This can co-exist safely with architecture-specific handling, until the latter has been removed. 4. Patch 6 removes the non-standard handling of "linux,elfcorehdr" on riscv. 5. Patches 7-8 convert arm64 to use the generic handling instead of its own implementation. 6. Patch 9 adds support for kdump properties to arm32. The corresponding patch for kexec-tools is "[PATCH] arm: kdump: Add DT properties to crash dump kernel's DTB"[3], which is still valid. Changes compared to v4[4]: - New patch "[PATCH v5 1/9] MIPS: Avoid future duplicate elf core header reservation", - Drop "memblock: Add variables for usable memory limitation", as this is now handled in FDT core code, - Make ELFCORE_ADDR_{MAX,ERR} visible, too, - Handle the actual elf core header reservation and memory capping in FDT core code, - Add Reviewed-by, Acked-by, - Remove all architecture-specific handling on arm64, - Drop "arm64: kdump: Use IS_ENABLED(CONFIG_CRASH_DUMP) instead of #ifdef", as the affected code is gone, - Remove the addition of "linux,elfcorehdr" and "linux,usable-memory-range" handling to arch/arm/mm/init.c. Changes compared to older versions: - Make elfcorehdr_{addr,size} always visible, - Add variables for usable memory limitation, - Use IS_ENABLED() instead of #ifdef (incl. initrd and arm64), - Clarify what architecture-specific code is still responsible for, - Add generic support for parsing linux,usable-memory-range, - Remove custom linux,usable-memory-range parsing on arm64, - Use generic handling on ARM. This has been tested with kexec/kdump on arm32 and arm64, and boot-tested on riscv64 and DT-less MIPS. Thanks! [1] "[PATCH v3] ARM: Parse kdump DT properties" https://lore.kernel.org/r/20210317113130.2554368-1-geert+renesas@xxxxxxxxx/ [2] "[PATCH 0/3] Add generic-support for linux,elfcorehdr and fix riscv" https://lore.kernel.org/r/cover.1623780059.git.geert+renesas@xxxxxxxxx/ [3] "[PATCH] arm: kdump: Add DT properties to crash dump kernel's DTB" https://lore.kernel.org/r/20200902154129.6358-1-geert+renesas@xxxxxxxxx/ [4] "[PATCH v4 00/10] Add generic support for kdump DT properties" https://lore.kernel.org/r/cover.1626266516.git.geert+renesas@xxxxxxxxx Geert Uytterhoeven (9): MIPS: Avoid future duplicate elf core header reservation crash_dump: Make elfcorehdr address/size symbols always visible of: fdt: Add generic support for handling elf core headers property of: fdt: Add generic support for handling usable memory range property of: fdt: Use IS_ENABLED(CONFIG_BLK_DEV_INITRD) instead of #ifdef riscv: Remove non-standard linux,elfcorehdr handling arm64: kdump: Remove custom linux,elfcorehdr handling arm64: kdump: Remove custom linux,usable-memory-range handling ARM: uncompress: Parse "linux,usable-memory-range" DT property Documentation/devicetree/bindings/chosen.txt | 12 +-- .../arm/boot/compressed/fdt_check_mem_start.c | 48 ++++++++-- arch/arm64/mm/init.c | 88 ----------------- arch/mips/kernel/setup.c | 3 +- arch/riscv/mm/init.c | 20 ---- drivers/of/fdt.c | 94 +++++++++++++++++-- include/linux/crash_dump.h | 3 +- 7 files changed, 139 insertions(+), 129 deletions(-) -- 2.25.1 Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds