Date: Wed, 25 Aug 2010 10:10:45 -0700
From: Greg KH <gregkh@suse.de>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Kay Sievers <kay.sievers@vrfy.org>, Samo Pogacnik <samo_pogacnik@t-2.net>,
        linux kernel <linux-kernel@vger.kernel.org>,
        linux-embedded <linux-embedded@vger.kernel.org>
Subject: Re: [PATCH] detour TTY driver - now ttyprintk
Message-ID: <20100825171045.GA19401@suse.de>
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 <20100824225703.GA5913@suse.de>
 <20100825002221.68fc09a4@lxorguk.ukuu.org.uk>
 <20100824231241.GA6971@suse.de>
 <20100825005152.40ba2f12@lxorguk.ukuu.org.uk>
 <20100825004134.GA28884@suse.de>
 <20100825110813.5f7d7ac8@lxorguk.ukuu.org.uk>
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On Wed, Aug 25, 2010 at 06:11:08PM +0100, Alan Cox wrote:
> > Would that work for this driver in use as a console?
> 
> Yes
> 
> >   exec < /dev/console > /dev/kmsg 2>&1
> > 
> > That's one extra process, not that much, right?
> 
> About 150K or so way too much and its not robust.

Fair enough.  So, with this driver, would it make sense for the distros
to switch over to using it instead of the above line in their initrd?

> > > You also want errors to get out (or stored) even if there are crashes -
> > > which the Fedora one is not very good at. To be fair in the Fedora world
> > > its not a big deal to say 'Oh dear, boot with ....'. Embedded isn't the
> > > same, and you want to capture the odd rare error reliably.
> > 
> > again, the above exec line should work for what the embedded people
> > want, right?
> 
> We didn't *need* devtmpfs either - that was a little bit of user space.
> It's a similar thing - you can do the job better in 1.5K of kernel code
> than 150K or more of user space - which is not trivial on a box with no
> swap.

Ok, I didn't realize it really was that big.

Samo, care to resend the patch?

thanks,

greg k-h
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