From: Samuel Thibault <samuel.thibault@ens-lyon.org>
To: "Ted Ts'o" <tytso@mit.edu>, "John G. Heim" <jheim@math.wisc.edu>,
Alan Cox <alan@lxorguk.ukuu.org.uk>,
linux-kernel@vger.kernel.org
Subject: Re: speakup bug
Date: Sun, 4 Mar 2012 01:43:48 +0100 [thread overview]
Message-ID: <20120304004348.GR4180@type.famille.thibault.fr> (raw)
In-Reply-To: <20120304004116.GA3042@thunk.org>
Ted Ts'o, le Sat 03 Mar 2012 19:41:16 -0500, a écrit :
> On Sun, Mar 04, 2012 at 01:21:11AM +0100, Samuel Thibault wrote:
> > Samuel Thibault, le Sun 04 Mar 2012 01:18:06 +0100, a écrit :
> > > Just for the record: what we need is being able to open a serial port
> > > and read/write from inside the kernel. Using a daemon that does the open
> > > and setting up speakup as a line discipline would be possible, but it
> > > then depends on / working, and that's not something e.g. administrators
> > > can really afford depending on.
> >
> > BTW: yes, that does not mean that speakup couldn't use a line discipline
> > already. Sure, still on the TODO list for years too.
>
> Actualy you *can* open a tty from the kernel. Look at how
> /dev/console is opened in kernel_init() in init/main.c.
But that still needs /dev
> If you don't even want a dependency on /, life gets a little harder,
> but is that really that important?
Yes. It does happen that / can not be mounted: disk encryption, disk
failure, nfs failure, etc. And without any feedback, it's very hard to
know what happened.
> The advantages of doing it cleanly
> is that it will work on systems that don't have a normal serial port,
> but only have a USB interface (for example, if you were going to try
> to hack in support for a mobile device or some other embedded system).
Sure! But there should be a way to do it without /, just like the
serial console works on ttyUSB0 without /.
Samuel
next prev parent reply other threads:[~2012-03-04 0:43 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-03 17:18 John G. Heim
2012-03-03 17:39 ` Alan Cox
2012-03-03 22:01 ` Ted Ts'o
2012-03-04 0:01 ` John G. Heim
2012-03-04 0:18 ` Samuel Thibault
2012-03-04 0:21 ` Samuel Thibault
2012-03-04 0:41 ` Ted Ts'o
2012-03-04 0:43 ` Samuel Thibault [this message]
2012-03-04 0:44 ` Samuel Thibault
2012-03-04 1:41 ` Ted Ts'o
2012-03-04 0:26 ` Ted Ts'o
2012-03-04 2:03 ` John G. Heim
2012-03-04 21:06 ` Alan Cox
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