Subject: Re: [PATCH v15 00/23] arm64/riscv: Add support for crashkernel CMA reservation

From: Baoquan He <[email-masked]>
Date: Mon, 1 Jun 2026 21:40:23 +0800

Hi Jinjie,

On 06/01/26 at 05:47pm, Jinjie Ruan wrote:
...snip... 
> Changes in v15:
> - Unify the subject prefix formats as Huacai suggested.
> - Fix powerpc pre-existing NULL pointer dereference [Sashiko [1]]
> - Fix powerpc pre-existing __merge_memory_ranges() memory range
>   truncation [Sashiko [1]].
> - Fix pre-existing arm64 CMA page leaks [Sashiko[2]].
> - Fix pre-existing crash_load_dm_crypt_keys() Use-After-Free and
>   Double Free issue [Sashiko[3]].
> - Fix vfree(headers) and uninitialized variables issue
>   and simplify the fix [Sashiko[2]].
> - As walk_system_ram_res() and for_each_mem_range() use different
>   lock, unify and simplify the fix of TOCTOU buffer overflow via memory
>   region padding [Sashiko[4]].
> - Fix the arm64 crash dump issues in Sashiko[5].
> - Link to v14: https://lore.kernel.org/all/[email-masked]/

Do these Fixes have anything with the main target of this patch series
you mentioned in cover-letter:"arm64/riscv: Add support for crashkernel CMA"?
The patches become more and more in each new version, I am wondering if
it relies on these Fixes patches to implement your adding support for
crashkernel CMA on arm64/risc-v.

If not relying on them, could you split them into different patchset
on different purpose? 

Thanks
Baoquan

> 
> [1]: https://lore.kernel.org/all/[email-masked]/
> [2]: https://lore.kernel.org/all/[email-masked]/
> [3]: https://lore.kernel.org/all/[email-masked]/
> [4]: https://lore.kernel.org/all/[email-masked]/
> [5]: https://lore.kernel.org/all/[email-masked]/
> 
> Changes in v14:
> - Fix image->elf_headers memory leak during retry loop for arm64 as Sashiko
>   AI code review pointed out.
> - Solve the hotplug notifier arch_crash_handle_hotplug_event() AA
>   self-deadlock problem as Sashiko AI code review pointed out.
> - Fix the TOCTOU issue in prepare_elf_headers() by get_online_mems().
> - -ENOMEM -> -EAGAIN as Breno suggested.
> - Add support for arm64 crash hotplug.
> - Link to v13: https://lore.kernel.org/all/[email-masked]/
> 
> Changes in v13:
> - Rebased on v7.1-rc1.
> - Update the commit message.
> - Add Reviewed-by.
> - Link to v12: https://lore.kernel.org/all/[email-masked]/
> 
> Changes in v12:
> - Remove the unused "nr_mem_ranges" for x86.
> - Add "Fix crashk_low_res not exclude bug" test log.
> - Provide a separate patch for each architecture for using
>   crash_prepare_headers(), which will make the review more convenient.
> - Add Reviewed-by and Tested-by.
> - Link to v11: https://lore.kernel.org/all/[email-masked]/
> 
> Changes in v11:
> - Avoid silently drop crash memory if the crash kernel is built without
>   CONFIG_CMA.
> - Remove unnecessary "cmem->nr_ranges = 0" for arch_crash_populate_cmem()
>   as we use kvzalloc().
> - Provide a separate patch for each architecture to fix the existing
>   buffer overflow issue.
> - Add Acked-bys for arm64.
> 
> Changes in v10:
> - Fix crashk_low_res not excluded bug in the existing
>   RISC-V code.
> - Fix an existing memory leak issue in the existing PowerPC code.
> - Fix the ordering issue of adding CMA ranges to
>   "linux,usable-memory-range".
> - Fix an existing concurrency issue. A Concurrent memory hotplug may occur
>   between reading memblock and attempting to fill cmem during kexec_load()
>   for almost all existing architectures.
> - Link to v9: https://lore.kernel.org/all/[email-masked]/
> 
> Changes in v9:
> - Collect Reviewed-by and Acked-by, and prepare for Sashiko AI review.
> - Link to v8: https://lore.kernel.org/all/[email-masked]/
> 
> Changes in v8:
> - Fix the build issues reported by kernel test robot and Sourabh.
> - Link to v7: https://lore.kernel.org/all/[email-masked]/
> 
> Changes in v7:
> - Correct the inclusion of CMA-reserved ranges for kdump kernel in of/kexec
>   for arm64 and riscv.
> - Add Acked-by.
> - Link to v6: https://lore.kernel.org/all/[email-masked]/
> 
> 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/[email-masked]/
> 
> Jinjie Ruan (22):
>   riscv: kexec_file: Fix crashk_low_res not exclude bug
>   powerpc/crash: Fix possible memory leak in update_crash_elfcorehdr()
>   powerpc/kexec_file: Fix NULL pointer dereference in
>     kexec_extra_fdt_size_ppc64()
>   powerpc/kexec_file: Fix memory range truncation in
>     __merge_memory_ranges()
>   kexec: Extract kexec_free_segment_cma() from kimage_free_cma()
>   arm64: kexec_file: Fix CMA page leaks during segment placement retry
>     loops
>   arm64: kexec_file: Fix image->elf_headers memory leak during retry
>     loop
>   kexec: Fix UAF and Double Free in crash_load_dm_crypt_keys()
>   crash_core: Introduce CRASH_HOTPLUG_SAFETY_PADDING for memory hotplug
>     safety
>   x86: kexec_file: Fix TOCTOU buffer overflow via memory region padding
>   arm64: kexec_file: Fix TOCTOU buffer overflow via memory region
>     padding
>   riscv: kexec_file: Fix TOCTOU buffer overflow via memory region
>     padding
>   LoongArch: kexec_file: Fix TOCTOU buffer overflow via memory region
>     padding
>   crash: Add crash_prepare_headers() to exclude crash kernel memory
>   arm64: kexec_file: Use crash_prepare_headers() helper to simplify code
>   x86: kexec_file: Use crash_prepare_headers() helper to simplify code
>   riscv: kexec_file: Use crash_prepare_headers() helper to simplify code
>   LoongArch: kexec_file: Use crash_prepare_headers() helper to simplify
>     code
>   powerpc/kexec_file: Use crash_exclude_core_ranges() helper
>   arm64: kexec_file: Add support for crashkernel CMA reservation
>   riscv: kexec_file: Add support for crashkernel CMA reservation
>   arm64: crash: Add crash hotplug support
> 
> Sourabh Jain (1):
>   powerpc/crash: sort crash memory ranges before preparing elfcorehdr
> 
>  .../admin-guide/kernel-parameters.txt         |  16 +-
>  arch/arm64/Kconfig                            |   3 +
>  arch/arm64/include/asm/kexec.h                |  13 ++
>  arch/arm64/kernel/Makefile                    |   2 +-
>  arch/arm64/kernel/crash.c                     | 152 ++++++++++++++++++
>  arch/arm64/kernel/kexec_image.c               |  34 ++++
>  arch/arm64/kernel/machine_kexec_file.c        |  78 ++-------
>  arch/arm64/mm/init.c                          |   5 +-
>  arch/loongarch/kernel/machine_kexec_file.c    |  44 ++---
>  arch/powerpc/include/asm/kexec_ranges.h       |   1 -
>  arch/powerpc/kexec/crash.c                    |   7 +-
>  arch/powerpc/kexec/file_load_64.c             |   3 +
>  arch/powerpc/kexec/ranges.c                   | 113 ++-----------
>  arch/riscv/kernel/machine_kexec_file.c        |  43 ++---
>  arch/riscv/mm/init.c                          |   5 +-
>  arch/x86/kernel/crash.c                       |  92 ++---------
>  drivers/of/fdt.c                              |   9 +-
>  drivers/of/kexec.c                            |   9 ++
>  include/linux/crash_core.h                    |  15 ++
>  include/linux/crash_reserve.h                 |   4 +-
>  include/linux/kexec.h                         |   2 +
>  kernel/crash_core.c                           |  89 +++++++++-
>  kernel/crash_dump_dm_crypt.c                  |   4 +-
>  kernel/kexec_core.c                           |  25 +--
>  24 files changed, 430 insertions(+), 338 deletions(-)
>  create mode 100644 arch/arm64/kernel/crash.c
> 
> -- 
> 2.34.1
>