Re: [PATCH v9 4/4] crypto: Add Allwinner Security System crypto accelerator

From: Herbert Xu
Date: Sat May 23 2015 - 23:33:33 EST


On Sat, May 23, 2015 at 04:35:36PM +0200, Boris Brezillon wrote:
>
> > Since all SG I get was always a multiple of 16 (AES BLOCK SIZE) it was a sort of confirmation.
> >
> > Herbert ? does am I right or a chunking test is missing for cbc(aes) in testmgr.h
>
> Okay, just sharing my vision of this thing (I'll let Herbert comment on
> this aspect): I'd say that theoretically nothing prevents one from
> splitting its sg list in chunks smaller than the block size, so I'd
> say you should use the same trick for AES.

Indeed, you must be able to handle a block that straddles two SG
entries. If the hardware is not capable then you have to linearise
it by copying or use a fallback.

I can't believe we don't have a generic test for this in testmgr.

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