Re: [PATCH v5 4/4] crypto: Add Allwinner Security System crypto accelerator

Herbert Xu
2014-10-31T10:06:16Z

On Fri, Oct 31, 2014 at 10:57:06AM +0100, Maxime Ripard wrote:
>
> On a 3.18-rc2 kernel:
>
> $ git grep kmap -- crypto/
> crypto/ahash.c: walk->data = kmap(walk->pg);
> crypto/ahash.c: walk->data = kmap_atomic(walk->pg);
> crypto/async_tx/async_memcpy.c: dest_buf = kmap_atomic(dest) + dest_offset;
> crypto/async_tx/async_memcpy.c: src_buf = kmap_atomic(src) + src_offset;
> crypto/scatterwalk.c: return kmap_atomic(scatterwalk_page(walk)) +
> crypto/shash.c: data = kmap_atomic(sg_page(sg));
> crypto/shash.c: data = kmap_atomic(sg_page(sg));
>
> None of the drivers are.

What do you mean? It's precisely because the page can be in highmem
that we are mapping it. If it's not in highmem it'll be a noop.

Admittedly I haven't tested highmem since moving over to x86-64
some years ago, but it definitely used to work on x86-32.

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