Re: [PATCH v6 1/2] Provide in-kernel headers to make extending kernel easier

From: Daniel Colascione <dancol@google.com>
To: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Joel Fernandes <joel@joelfernandes.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Alexei Starovoitov <ast@kernel.org>,
	atish patra <atishp04@gmail.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Guenter Roeck <groeck@chromium.org>,
	Jonathan Corbet <corbet@lwn.net>,
	Karim Yaghmour <karim.yaghmour@opersys.com>,
	Kees Cook <keescook@chromium.org>,
	"Cc: Android Kernel" <kernel-team@android.com>,
	"open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
	"open list:KERNEL SELFTEST FRAMEWORK" 
	<linux-kselftest@vger.kernel.org>,
	linux-trace-devel@vger.kernel.org,
	Manoj Rao <linux@manojrajarao.com>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Qais Yousef <qais.yousef@arm.com>,
	Randy Dunlap <rdunlap@infradead.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Shuah Khan <shuah@kernel.org>, Yonghong Song <yhs@fb.com>
Subject: Re: [PATCH v6 1/2] Provide in-kernel headers to make extending kernel easier
Date: Fri, 12 Apr 2019 20:18:49 -0700	[thread overview]
Message-ID: <CAKOZuetDdtGoN8aNm6KF2N3Oz-QGO3PeTex=7VLoem_jDeaknw@mail.gmail.com> (raw)
In-Reply-To: <CAK7LNAS8LroP_N76ZS2OLZKaxSMA3UubdE1r7QzkqCt-TFmnWA@mail.gmail.com>

On Fri, Apr 12, 2019 at 8:10 PM Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> On Sat, Apr 13, 2019 at 11:58 AM Masahiro Yamada
> <yamada.masahiro@socionext.com> wrote:
> >
> > On Sat, Apr 13, 2019 at 10:53 AM Daniel Colascione <dancol@google.com> wrote:
> > >
> > > On Fri, Apr 12, 2019 at 6:49 PM Masahiro Yamada
> > > <yamada.masahiro@socionext.com> wrote:
> > > >
> > > > On Sat, Apr 13, 2019 at 3:02 AM Joel Fernandes <joel@joelfernandes.org> wrote:
> > > >
> > > > >
> > > > > > > +extern char kernel_headers_data;
> > > > > > > +extern char kernel_headers_data_end;
> > > > > > > +
> > > > > > > +static ssize_t
> > > > > > > +ikheaders_read_current(struct file *file, char __user *buf,
> > > > > >
> > > > > > Could you stretch this line ?
> > > > > > It will still fit in 80-cols.
> > > > > >
> > > > > > (This is a coding style error in kernel/configs.c)
> > > > >
> > > > > It takes 87 cols if I expand, so I'll leave it as is.
> > > > >
> > > >
> > > >
> > > > Sorry if what I said was unclear.
> > > >
> > > > Since I just did not a good reason to put
> > > > "static ssize_t" in the previous line,
> > > > I meant like follows:
> > > >
> > > >
> > > > [Before]
> > > > static ssize_t
> > > > ikheaders_read_current(struct file *file, char __user *buf,
> > > >                        size_t len, loff_t *offset)
> > > >
> > > >
> > > >
> > > > [After]
> > > > static ssize_t ikheaders_read_current(struct file *file, char __user *buf,
> > > >                                       size_t len, loff_t *offset)
> > > >
> > > >
> > > > (takes 74-cols.)
> > > >
> > > >
> > > > (I am sending this from Gmail, so I am not sure
> > > > how it will look like from you...)
> > > >
> > > >
> > > > Anyway, it is super-bikeshedding stuff.
> > > > It is OK as-is.
> > > >
> > >
> > > What about sorting the files for determinism?
> >
> >
> > Do you mean the order of files in the tar archive?

Yes.

> > I think it is a good idea for reproducible build.
> >
> >
> >
> > It looks like the tar command supports --sort=name option,
> > but I did not test it at all.
> >
> >
> >
> > Perhaps, the sorting policy could be affected by locale.
> > We saw it for the 'find' command.
>
>
> 'sort' command is affected by locale.

It should be independent of locale if you set LC_ALL=C in the
environment while running it.