Re: [dm-devel] [PATCH v10 2/7] fs: crypto: invoke crypto API for ESSIV handling

From: Eric Biggers <ebiggers@kernel.org>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" 
	<linux-crypto@vger.kernel.org>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	device-mapper development <dm-devel@redhat.com>,
	linux-fscrypt@vger.kernel.org,
	Gilad Ben-Yossef <gilad@benyossef.com>,
	Milan Broz <gmazyland@gmail.com>
Subject: Re: [dm-devel] [PATCH v10 2/7] fs: crypto: invoke crypto API for ESSIV handling
Date: Tue, 13 Aug 2019 11:00:21 -0700	[thread overview]
Message-ID: <20190813180020.GA233786@gmail.com> (raw)
In-Reply-To: <CAKv+Gu-9aHY0op6MEmN8PfQhNa0kv=xNYB6rqtaCoiUdH4OASA@mail.gmail.com>

On Tue, Aug 13, 2019 at 08:09:41AM +0300, Ard Biesheuvel wrote:
> On Mon, 12 Aug 2019 at 22:47, Eric Biggers <ebiggers@kernel.org> wrote:
> >
> > On Mon, Aug 12, 2019 at 05:53:19PM +0300, Ard Biesheuvel wrote:
> > > Instead of open coding the calculations for ESSIV handling, use a
> > > ESSIV skcipher which does all of this under the hood.
> > >
> > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> >
> > This looks fine (except for one comment below), but this heavily conflicts with
> > the fscrypt patches planned for v5.4.  So I suggest moving this to the end of
> > the series and having Herbert take only 1-6, and I'll apply this one to the
> > fscrypt tree later.
> >
> 
> I think the same applies to dm-crypt: at least patch #7 cannot be
> applied until my eboiv patch is applied there as well, but [Milan
> should confirm] I'd expect them to prefer taking those patches via the
> dm tree anyway.
> 
> Herbert, what would you prefer:
> - taking a pull request from a [signed] tag based on v4.3-rc1 that
> contains patches #1, #4, #5 and #6, allowing Eric and Milan/Mike to
> merge it as well, and apply the respective fscrypt and dm-crypt
> changes on top
> - just take patches #1, #4, #5 and #6 as usual, and let the fscrypt
> and dm-crypt changes be reposted to the respective lists during the
> next cycle
> 

FWIW I'd much prefer the second option, to minimize the number of special things
that Linus will have to consider or deal with.  (There's also going to be a
conflict between the fscrypt and keyrings trees.)  I'd be glad to take the
fscrypt patch for 5.5, if the essiv template is added in 5.4.

- Eric