Re: [PATCH v2] crypto: aesni - add ccm(aes) algorithm implementation

From: Eric Biggers <ebiggers@kernel.org>
To: Ben Greear <greearb@candelatech.com>
Cc: Ard Biesheuvel <ardb@kernel.org>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	Linux Crypto Mailing List <linux-crypto@vger.kernel.org>
Subject: Re: [PATCH v2] crypto: aesni - add ccm(aes) algorithm implementation
Date: Mon, 16 Oct 2023 20:16:03 -0700	[thread overview]
Message-ID: <20231017031603.GB1907@sol.localdomain> (raw)
In-Reply-To: <32a44a29-c5f4-f5fa-496f-a9dc98d8209d@candelatech.com>

On Mon, Oct 16, 2023 at 01:50:05PM -0700, Ben Greear wrote:
> On 11/12/22 06:59, Ard Biesheuvel wrote:
> > On Fri, 11 Nov 2022 at 23:29, Ben Greear <greearb@candelatech.com> wrote:
> > > 
> > > On 11/9/22 2:05 AM, Ard Biesheuvel wrote:
> > > > On Wed, 9 Nov 2022 at 04:52, Herbert Xu <herbert@gondor.apana.org.au> wrote:
> > > > > 
> > > > > On Tue, Nov 08, 2022 at 10:50:48AM -0800, Ben Greear wrote:
> > > > > > 
> > > > > > While rebasing my patches onto 6.1-rc4, I noticed my aesni for ccm(aes) patch didn't apply cleanly,
> > > > > > and I found this patch described below is applied now.  Does this upstream patch mean that aesni is already
> > > > > > supported upstream now?  Or is it specific to whatever xctr is?  If so,
> > > > > > any chance the patch is wanted upstream now?
> > > > > 
> > > > > AFAICS the xctr patch has nothing to do with what you were trying
> > > > > to achieve with wireless.  My objection still stands with regards
> > > > > to wireless, we should patch wireless to use the async crypto
> > > > > interface and not hack around it in the Crypto API.
> > > > > 
> > > > 
> > > > Indeed. Those are just add/add conflicts because both patches
> > > > introduce new code into the same set of files. The resolution is
> > > > generally to keep both sides.
> > > > 
> > > > As for Herbert's objection: I will note here that in the meantime,
> > > > arm64 now has gotten rid of the scalar fallbacks entirely in AEAD and
> > > > skipcher implementations, because those are only callable in task or
> > > > softirq context, and the arm64 SIMD wrappers now disable softirq
> > > > processing. This means that the condition that results in the fallback
> > > > being needed can no longer occur, making the SIMD helper dead code on
> > > > arm64.
> > > > 
> > > > I suppose we might do the same thing on x86, but since the kernel mode
> > > > SIMD handling is highly arch specific, you'd really need to raise this
> > > > with the x86 maintainers.
> > > > 
> > > 
> > > Hello Ard,
> > > 
> > > Could you please review the attached patch to make sure I merged it properly?  My concern
> > > is the cleanup section and/or some problems I might have introduced related to the similarly
> > > named code that was added upstream.
> > > 
> > 
> > I don't think the logic is quite right, although it rarely matter.
> > 
> > I've pushed my version here - it invokes the static call for CTR so it
> > will use the faster AVX version if the CPU supports it.
> > 
> > https://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git/log/?h=aesni-ccm-v6.1
> 
> Hello Ard,
> 
> It looks like something changed again in the intel-aesni logic for 6.6 kernel.  I was able to do a small
> change to the patch to get it to compile, but the kernel crashes when I bring up a wlan port in
> 6.6.  When I remove the aesni patch, the station comes up without crashing.  The aesni patch worked
> fine in 6.5 as far as I can tell.
> 
> I'm attaching my slightly modified version of the patch you sent previous.  If you have time to
> investigate this it would be much appreciated.
> 
> Thanks,
> Ben

If this patch is useful, shouldn't it be upstreamed?

- Eric