From: Kees Cook <keescook@chromium.org>
To: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>,
linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
"Gustavo A. R. Silva" <gustavo@embeddedor.com>
Subject: Re: [PATCH] docs: deprecated.rst: Add note to the use of struct_size() helper
Date: Thu, 4 Jun 2020 14:33:47 -0700 [thread overview]
Message-ID: <202006041433.7065E1A7@keescook> (raw)
In-Reply-To: <20200604211903.GF10051@embeddedor>
On Thu, Jun 04, 2020 at 04:19:03PM -0500, Gustavo A. R. Silva wrote:
> On Thu, Jun 04, 2020 at 01:25:26PM -0700, Kees Cook wrote:
> > On Thu, Jun 04, 2020 at 01:21:23PM -0500, Gustavo A. R. Silva wrote:
> > > Yeah. My reasoning for is that it will take a while --at least one
> > > development cycle more-- to completely get rid of all the 0/1-arrays.
> >
> > Right -- but we need a place to point people when we tell them "please
> > don't use 0-byte and 1-byte arrays", and the deprecated.rst is the place
> > for that.
> >
> > Having it in deprecated.rst once they're all gone only serves to explain
> > why various compiler flags are enabled, etc. But while they're being
> > removed, it serves as a single place to document the issue (as in, much
> > of the flex-array patch commit log "boilerplate" can actually be
> > repeated in deprecated.rst.
> >
> > > But I think we can add this note while I continue working on the flexible-array
> > > conversions. Once that work is complete, I can go back and update the
> > > documentation. :)
> > >
> > > What do you think?
> >
> > I think we need to document it at the beginning of the work (and I
> > should have asked for this earlier). So let's just add a new section on
> > dynamic array usage, etc. It can include a note about struct_size() as
> > an example for why 1-byte arrays are so weird. :)
> >
>
> Got ya. :)
>
> One last thing... I was thinking on adding such section (dynamic array
> usage) to coding-style.rst, explaining how to use struct_size() and
> transform the different open-coded versions we currently have in the
> kernel, e.g. I have seen people use offsetof() --and sometimes open-coded
> versions of sizeof_field()-- and its open-coded version to do arithmetic
> in allocator arguments.
Yeah, that sounds good to me!
-Kees
>
> Thanks
> --
> Gustavo
>
--
Kees Cook
prev parent reply other threads:[~2020-06-04 21:33 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-04 17:21 [PATCH] docs: deprecated.rst: Add note to the use of struct_size() helper Gustavo A. R. Silva
2020-06-04 17:49 ` Kees Cook
2020-06-04 18:21 ` Gustavo A. R. Silva
2020-06-04 20:25 ` Kees Cook
2020-06-04 21:19 ` Gustavo A. R. Silva
2020-06-04 21:33 ` Kees Cook [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=202006041433.7065E1A7@keescook \
--to=keescook@chromium.org \
--cc=corbet@lwn.net \
--cc=gustavo@embeddedor.com \
--cc=gustavoars@kernel.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).