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

Herbert Xu
2022-04-15T10:12:38Z

On Fri, Apr 15, 2022 at 11:51:49AM +0200, Ard Biesheuvel wrote:
>
> That is the whole point, really: ARCH_DMA_MINALIGN==128 does not mean
> __ctx needs to be aligned to 128 bytes, it only means that it should
> not share a 128 byte cacheline with the preceding fields. So if
> kmalloc() returns buffers that are aligned to whatever alignment the
> platform requires (which will be 64 in most cases), the above
> arrangement ensures that, without requiring that CRYPTO_MINALIGN ==
> ARCH_DMA_MINALIGN.

What if they started sharing a cacheline with the subsequent object?
I guess you could add some more padding at the end though.

I could accept this as a temporary solution, if you volunteer to
modify all the affected drivers so we can get rid of this bandaid.

Thanks,
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
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