Re: [PATCH 07/10] crypto: Use ARCH_DMA_MINALIGN instead of ARCH_KMALLOC_MINALIGN

Herbert Xu
2022-04-15T06:51:54Z

On Wed, Apr 13, 2022 at 09:47:29AM +0100, Catalin Marinas wrote:
>
> With my series, there is no change to the value of CRYPTO_MINALIGN for
> arm64 or any other architecture, so point 3 is unaffected. The series
> does change the kmalloc() alignment and that may be smaller than
> CRYPTO_MINALIGN but neither of points 1 or 2 above are affected since
> (a) we still have a sufficiently large ARCH_KMALLOC_MINALIGN of 64 and
> (b) the kmalloc'ed buffers are safe for non-coherent DMA.
>
> Herbert, Ard, if I missed anything please let me know but based on my
> understanding, this series is safe for the crypto code.

Sorry, but you can't change CRYPTO_MINALIGN to a value greater
than the minimum alignment returned by kmalloc. That simply
doesn't work. There is no magic in the Crypto API that makes
this work.

Cheers,
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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