[PATCH 15/17] lib/crypto: s390/sha3: Migrate optimized code into library

[Eric Biggers]

On Tue, Oct 21, 2025 at 10:43:00AM +0200, Holger Dengler wrote:
> Hi Eric,
> 
> On 21/10/2025 09:24, Holger Dengler wrote:
> > On 20/10/2025 19:57, Eric Biggers wrote:
> [...]>> - Risk of bugs.  QEMU doesn't support the s390 SHA-3 instructions, so no
> >>   one except the s390 folks can test the code.  I can try to write code
> >>   for you, but I can't test it.  And the s390 SHA-3 code has had bugs;
> >>   see commits 992b7066800f, 68279380266a5, 73c2437109c3.
> >>
> >>   The first priority should be correctness.
> > 
> > Let me figure out, if me and my colleagues can do the testing for you.
> > Unfortunately, I'll be unavailable for the next two weeks. But I'll come back
> > with a solution for the testing.
> 
> I talked to Harald: we can do the testing for you on our development machines.
> Please send new series to us or provide them in your git repo.

Thanks!  I'll Cc both of you on v2 when I send it later.  For now, this
series (v1) can be found in lore at
https://lore.kernel.org/linux-crypto/20251020005038.661542-1-ebiggers@kernel.org/T/#u
And as mentioned in the cover letter it's also retrievable from git:

    git fetch https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git sha3-lib-v1

v1 already has the s390 optimized implementations of
sha3_absorb_blocks() and sha3_keccakf().  If you could enable the
following:

    CONFIG_CRYPTO_LIB_SHA3_KUNIT_TEST=y
    CONFIG_CRYPTO_LIB_BENCHMARK=y

... and then show the results for sha3_kunit before and after the commit
"lib/crypto: s390/sha3: Migrate optimized code into library", that would
be helpful.

In v2, I'll look into providing overrides for the one-shot functions
sha3_{224,256,384,512}() too.  If it works out, I'll ask you to re-test
with that additional change as well.

- Eric