linux-kernel - Re: [PATCH] serial: rewrite pxa2xx-uart to use 8250

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 6 Dec 2013 20:53:45 +1100
From:	James Cameron <quozl@...top.org>
To:	Sergei Ianovich <ynvich@...il.com>
Cc:	Russell King - ARM Linux <linux@....linux.org.uk>,
	"open list:OPEN FIRMWARE AND..." <devicetree@...r.kernel.org>,
	Heikki Krogerus <heikki.krogerus@...ux.intel.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Ralf Baechle <ralf@...ux-mips.org>,
	linux-kernel@...r.kernel.org,
	Rob Herring <rob.herring@...xeda.com>,
	Haojian Zhuang <haojian.zhuang@...il.com>,
	"open list:SERIAL DRIVERS" <linux-serial@...r.kernel.org>,
	Grant Likely <grant.likely@...aro.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	John Crispin <blogic@...nwrt.org>, Jiri Slaby <jslaby@...e.cz>,
	"moderated list:ARM PORT" <linux-arm-kernel@...ts.infradead.org>,
	Zhou Zhu <zzhu3@...vell.com>
Subject: Re: [PATCH] serial: rewrite pxa2xx-uart to use 8250_core

On Fri, Dec 06, 2013 at 01:28:51PM +0400, Sergei Ianovich wrote:
> On Fri, 2013-12-06 at 00:17 +0000, Russell King - ARM Linux wrote:
> 
> > I may be able to - one of the downsides though is that many of these
> > systems had hard-coded scripts which started a getty on the original
> > port - and that kind of makes it difficult to sort out.  This kind of
> > change becomes very much one of Linus' "flag days".
> 
> > So I'd suggest that we have a period where the old driver is still
> > available, so at least people can choose to use the old major/minor
> > numbers for a while.
> 
> The patch doesn't change how the driver looks from the outside. The old
> driver was using 8250 name (ttyS), major (4) and first minor (64). So we
> only resolve an internal conflict.

I don't understand why /dev/ttyS2 (4,66) changed to /dev/ttyS0 (4,64)
after the patch was applied to olpc-kernel/arm-3.5 but, as you say it
doesn't change, perhaps there is something between 3.5 and now for me
to watch out for.  My problem.

> Kernel configuration is the place where issues may appear, since the
> patch removes CONFIG_SERIAL_PXA_CONSOLE option. I've updated all
> in-kernel users. However, out-of-kernel configs will no longer provide
> serial console, unless manually reconfigured. Is this the case we should
> worry about?

OLPC holds an out-of-kernel config (xo_4_defconfig); but no, I don't
think we'd have trouble with this.  Go for it.

-- 
James Cameron
http://quozl.linux.org.au/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/