[PATCH v3 0/2] riscv: kexec_file: Support loading Image binary file

[Björn Töpel]

From: Björn Töpel <bjorn at rivosinc.com>

Hi!

For over a year ago, Daniel and I was testing the V2 of Song's series.
I also promised to take the V2, that had been sitting on the lists for
too long, to rebase it on a new kernel, and re-test it.

One year later, here's the V3! ;-)

There are no changes from V2 other, than some simple checkpatch
cleanups.

Song's original cover:
  | This series makes the kexec_file_load() syscall support to load
  | Image binary file. At the same time, corresponding support for
  | kexec-tools had been pushed to my repo[2].
  |
  | Now, we can leverage that kexec-tools and this series to use the
  | kexec_load() or kexec_file_load() syscall to boot both vmlinux and
  | Image file, as seen in these combo tests:
  |
  | ```
  | 1. kexec -l vmlinux
  | 2. kexec -l Image
  | 3. kexec -s -l vmlinux
  | 4. kexec -s -l Image
  | ```

Notably, kexec-tools has still not made it upstream. I've prepared a
branch on my GH [3], that I indend to post ASAP. That branch is a
collection of fixes/features, including Song's userland Image loading.

The V2 is here [2], and V1 [1].

I've tested the kexec-file/Image on qemu-rv64, with following
combinations:
 * ACPI/UEFI 
 * DT/UEFI
 * DT

both "regular" kexec (-s + -e), and crashkernels (-p).

Note that there are two purgatory patches that has to be present (part
of -rc1, so all good):
  commit 28093cfef5dd ("riscv/kexec_file: Handle R_RISCV_64 in purgatory relocator")
  commit 3f7023171df4 ("riscv/purgatory: 4B align purgatory_start")

[1] https://lore.kernel.org/linux-riscv/20230914020044.1397356-1-songshuaishuai@tinylab.org/
[2] https://lore.kernel.org/linux-riscv/20231016092006.3347632-1-songshuaishuai@tinylab.org/
[3] https://github.com/bjoto/kexec-tools/tree/rv-on-master

Song Shuai (2):
  riscv: kexec_file: Split the loading of kernel and others
  riscv: kexec_file: Support loading Image binary file

 arch/riscv/include/asm/image.h         |   2 +
 arch/riscv/include/asm/kexec.h         |   6 +
 arch/riscv/kernel/Makefile             |   2 +-
 arch/riscv/kernel/elf_kexec.c          | 485 -------------------------
 arch/riscv/kernel/kexec_elf.c          | 144 ++++++++
 arch/riscv/kernel/kexec_image.c        |  96 +++++
 arch/riscv/kernel/machine_kexec_file.c | 361 ++++++++++++++++++
 7 files changed, 610 insertions(+), 486 deletions(-)
 delete mode 100644 arch/riscv/kernel/elf_kexec.c
 create mode 100644 arch/riscv/kernel/kexec_elf.c
 create mode 100644 arch/riscv/kernel/kexec_image.c


base-commit: a24588245776dafc227243a01bfbeb8a59bafba9
-- 
2.45.2