[PATCH v2 0/2] arm64: csum: Add fused copy and Internet checksum

[Demian Shulhan <demyansh@gmail.com>]

Add a single-pass csum_partial_copy_nocheck() implementation for arm64
and extend the checksum KUnit suite to cover copy-and-checksum across
alignments, lengths, guard pages, and interrupt contexts.

Changes in v2:
- Drop the NEON path and separate csum-copy* files, folding the scalar
  implementation directly into arch/arm64/lib/csum.c (resolves the
  <asm/neon-intrinsics.h> include issue noted by Nathan Chancellor).
- Switch the scalar loop to four __uint128_t accumulators (David Laight).
- Canonicalize 0xffff (-0) to 0x0000 (+0) after csum_fold() in KUnit to
  fix x86_64 test failures on zero/all-zero inputs (Jakub Kicinski).

Link: https://lore.kernel.org/r/20260927131838.6774-1-demyansh@gmail.com

Demian Shulhan (2):
  arm64: csum: Add fused copy and Internet checksum
  lib/tests: checksum: Add KUnit tests for csum_partial_copy_nocheck()

 arch/arm64/include/asm/checksum.h |   3 +
 arch/arm64/lib/csum.c             | 100 ++++++++
 lib/Kconfig.debug                 |  10 +
 lib/tests/checksum_kunit.c        | 410 ++++++++++++++++++++++++++++++
 4 files changed, 523 insertions(+)


base-commit: 97d73c8251226cf27cc6656b4c542869bb8c69fa
-- 
2.53.0