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Date: Fri, 1 Sep 2017 09:29:06 +0200
From: Pavel Machek <pavel@ucw.cz>
To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Petr Mladek <pmladek@suse.com>, Steven Rostedt <rostedt@goodmis.org>,
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        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: printk: what is going on with additional newlines?
Message-ID: <20170901072906.GB12104@amd>
References: <20170815025625.1977-1-sergey.senozhatsky@gmail.com>
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On Fri 2017-09-01 10:40:12, Sergey Senozhatsky wrote:
> Hi,
>=20
> On (08/29/17 22:24), Pavel Machek wrote:
> > > > In 4.13-rc, printk("foo"); printk("bar"); seems to produce
> > > > foo\nbar. That's... quite surprising/unwelcome. What is going on
> > > > there? Are timestamps responsible?
> > >=20
> > > No.
> > >=20
> > > It's actively trying to treach you not to do shit.
> > >=20
> > > If you want to continue a line, you NEED to use KERN_CONT.
> > >=20
> > > That has always been true. It hasn't always been enforced, though.
> >=20
> > Dumping hex buffer for debugging should not be a rocket science. You
> > are welcome not add checkpatch rules to prevent such code from being
> > merged...
>=20
> well... just a note, I personally developed a new habit - use
> pr_err/pr_cont/etc macros instead of explicit printk(KERN_FOO "...").
> may be this can work for you. and we _probably_ need to advertise
> pr_foo() more.

Well, usually dev_info (and friends) is right thing to use for
production. But very little debugging remains after the
=2E. well.. debugging phase, so something that behaves similar to
printf() is nice.

Actually, I believe we should just create printf() in kernel. Its the
mistake I do all the time.

									Pavel
--=20
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo=
g.html

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