From mboxrd@z Thu Jan  1 00:00:00 1970
From: Muli Ben-Yehuda <mulix@mulix.org>
Subject: Re: [PATCH] xencons missing string allocation
Date: Fri, 09 Dec 2005 20:54:48 +0200
Message-ID: <20051209185448.GD9830@granada.merseine.nu>
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To: Alex Williamson <alex.williamson@hp.com>
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On Fri, Dec 09, 2005 at 11:37:31AM -0700, Alex Williamson wrote:

> 
>    I was trying to boot dom0 w/ "xencons=ttyS1 console=ttyS1".  It gives
> some weird error messages:
> 
> Warning: dev (ttyS2) tty->count(2) != #fd's(1) in release_dev
> Warning: dev (ttyS2) tty->count(3) != #fd's(1) in tty_open
> 
> And blows up with a page fault.  The page fault is because we don't
> actually allocate a buffer for the tty driver name.

Errr... the patch looks curious. Why does it work when ->name points
to the heap but not when it points to the data segment? they should be
equivalent and many tty drivers appear to set ->name to the data
segment. Is something trying to modify xencons_driver->name later?

(also, do you know why do we need the fugly DRV() macro in that code?)

Cheers,
Muli
-- 
Muli Ben-Yehuda
http://www.mulix.org | http://mulix.livejournal.com/