When CPU or memory hotplug events occur, the elfcorehdr in the kdump image
becomes stale, potentially leading to incomplete crash dumps.

Currently, userspace udev rules reload the entire kdump image upon such
events, which is inefficient and leaves kdump inactive for a long time.

Commit 247262756121 ("crash: add generic infrastructure for crash hotplug
support") introduced a kernel mechanism to update only the elfcorehdr.
This patch set implements crash hotplug support for arm64.

It also addresses and fixes several critical pre-existing code issues
and Sashiko AI review findings extracted from the previous patch set,
following Baoquan's suggestions.

The major improvements and fixes included in this series are:

- Fix powerpc memory leak, null-ptr-def and overlapping memory
  range truncation bug.

- Fix several memory leaks for arm64.

- Simplify arm64 load_other_segments().

- Implement infrastructure for arm64 crash memory hotplug support.

This patch set is rebased on liveupdate/crashkernel-cma.

Link: https://lore.kernel.org/all/20260601094805.2928614-1-ruanjinjie@huawei.com/

Jinjie Ruan (8):
  powerpc/crash: Fix possible memory leak in update_crash_elfcorehdr()
  powerpc/kexec_file: Fix null-ptr-def in extra size calculation
  powerpc/kexec_file: Prevent kexec range truncation
  kexec: Extract kexec_free_segment_cma() from kimage_free_cma()
  arm64: kexec_file: Fix CMA page leaks in segment placement retry loops
  arm64: kexec_file: Fix image->elf_headers memory leak during retry
    loop
  arm64: kexec_file: Simplify load_other_segments()
  arm64: crash: Add crash hotplug support

 arch/arm64/Kconfig                     |   3 +
 arch/arm64/include/asm/kexec.h         |  13 +++
 arch/arm64/kernel/Makefile             |   2 +-
 arch/arm64/kernel/crash.c              | 148 +++++++++++++++++++++++++
 arch/arm64/kernel/kexec_image.c        |   1 +
 arch/arm64/kernel/machine_kexec_file.c |  76 ++++++-------
 arch/powerpc/kexec/crash.c             |   2 +-
 arch/powerpc/kexec/file_load_64.c      |   2 +-
 arch/powerpc/kexec/ranges.c            |  12 +-
 include/linux/kexec.h                  |   2 +
 kernel/kexec_core.c                    |  25 +++--
 11 files changed, 223 insertions(+), 63 deletions(-)
 create mode 100644 arch/arm64/kernel/crash.c

-- 
2.34.1