Re: [PATCH] crypto: gcm - fix cacheline sharing

From: Herbert Xu
Date: Thu May 30 2019 - 09:30:08 EST


On Thu, May 30, 2019 at 01:18:34PM +0000, Horia Geanta wrote:
>
> I guess there are only two options:
> -either cache line sharing is avoided OR
> -users need to be *aware* they are sharing the cache line and some rules /
> assumptions are in place on how to safely work on the data

No there is a third option and it's very simple:

You must only access the virtual addresses given to you before DMA
mapping or after DMA unmapping.

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