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Date:   Thu, 3 Mar 2022 10:59:08 +1200
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     linux-crypto@vger.kernel.org, ebiggers@kernel.org
Subject: Re: [PATCH v2] crypto: crypto_xor - use helpers for unaligned
 accesses
Message-ID: <Yh/2vHEt+fGO3DlJ@gondor.apana.org.au>
References: <20220223070701.1457542-1-ardb@kernel.org>
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On Wed, Feb 23, 2022 at 08:07:01AM +0100, Ard Biesheuvel wrote:
> Dereferencing a misaligned pointer is undefined behavior in C, and may
> result in codegen on architectures such as ARM that trigger alignments
> traps and expensive fixups in software.
> 
> Instead, use the get_aligned()/put_aligned() accessors, which are cheap
> or even completely free when CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y.
> 
> In the converse case, the prior alignment checks ensure that the casts
> are safe, and so no unaligned accessors are necessary.
> 
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> ---
> v2: fix issue in crypto_xor_cpy()
> 
>  crypto/algapi.c         | 24 +++++++++++++++++---
>  include/crypto/algapi.h | 10 ++++++--
>  2 files changed, 29 insertions(+), 5 deletions(-)

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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