[PATCH v7 0/5] arm64/riscv: Add support for crashkernel CMA reservation

Jinjie Ruan
2026-02-26T13:05:40Z

The crash memory allocation, and the exclude of crashk_res, crashk_low_res
and crashk_cma memory are almost identical across different architectures,
This patch set handle them in crash core in a general way, which eliminate
a lot of duplication code.

And add support for crashkernel CMA reservation for arm64 and riscv.

Rebased on v7.0-rc1.

Basic second kernel boot test were performed on QEMU platforms for x86, ARM64,
and RISC-V architectures with the following parameters:

"cma=256M crashkernel=256M crashkernel=64M,cma"

Changes in v7:
- Correct the inclusion of CMA-reserved ranges for kdump kernel in of/kexec
for arm64 and riscv.
- Add Acked-by.

Changes in v6:
- Update the crash core exclude code as Mike suggested.
- Rebased on v7.0-rc1.
- Add acked-by.
- Link to v5: https://lore.kernel.org/all/20260212101001.343158-1-ruanjinjie@huawei.com/

Changes in v5:
- Fix the kernel test robot build warnings.
- Sort crash memory ranges before preparing elfcorehdr for powerpc
- Link to v4: https://lore.kernel.org/all/20260209095931.2813152-1-ruanjinjie@huawei.com/

Changes in v4:
- Move the size calculation (and the realloc if needed) into the
generic crash.
- Link to v3: https://lore.kernel.org/all/20260204093728.1447527-1-ruanjinjie@huawei.com/

Jinjie Ruan (4):
crash: Exclude crash kernel memory in crash core
crash: Use crash_exclude_core_ranges() on powerpc
arm64: kexec: Add support for crashkernel CMA reservation
riscv: kexec: Add support for crashkernel CMA reservation

Sourabh Jain (1):
powerpc/crash: sort crash memory ranges before preparing elfcorehdr

.../admin-guide/kernel-parameters.txt | 16 +--
arch/arm64/kernel/machine_kexec_file.c | 39 +++----
arch/arm64/mm/init.c | 5 +-
arch/loongarch/kernel/machine_kexec_file.c | 39 +++----
arch/powerpc/include/asm/kexec_ranges.h | 4 +-
arch/powerpc/kexec/crash.c | 5 +-
arch/powerpc/kexec/ranges.c | 101 +-----------------
arch/riscv/kernel/machine_kexec_file.c | 38 +++----
arch/riscv/mm/init.c | 5 +-
arch/x86/kernel/crash.c | 89 +++------------
drivers/of/fdt.c | 9 +-
drivers/of/kexec.c | 13 ++-
include/linux/crash_core.h | 9 ++
kernel/crash_core.c | 89 ++++++++++++++-
14 files changed, 183 insertions(+), 278 deletions(-)