[v5 PATCH 7/7] crypto: stm32 - Save and restore between each request

[Linus Walleij]

On Tue, Mar 7, 2023 at 11:10 AM Herbert Xu <herbert at gondor.apana.org.au> wrote:
> On Mon, Mar 06, 2023 at 11:08:13AM +0100, Linus Walleij wrote:
> >
> > This partly works (after my folded in fix in patch 5)!
> >
> > Clean SHA1 and SHA256 works flawlessly.
> > HMAC still fails, but not until we start testing random vectors:
> >
> > [    7.541954] alg: ahash: stm32-hmac-sha256 digest() failed on test
> > vector "random: psize=0 ksize=80"; expected_error=0,
> > actual_error=-110, cfg="random: may_sleep"
> > [    7.567212] alg: self-tests for hmac(sha256) using
> > stm32-hmac-sha256 failed (rc=-110)
>
> So it's timing out.  I wonder if the timeout in stm32_hash_wait_busy
> is long enough.  Perhaps try adding a zero so that the timeout becomes
> 100,000us and see if it still breaks?

Sadly this doesn't work.

I tried increasing with one and even two orders of magnitude,
but the timeouts still happen, usually two of them, sometimes
one sometimes three, depending on randomness, as can be
expected.

I think you mentioned something about that we need to store
the key in the state as well though?

Yours,
Linus Walleij