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From: Arnd Bergmann <arnd@arndb.de>
To: Tony Luck <tony.luck@intel.com>
Subject: Re: [PATCH] tty: avoid recursive BTM in pty_close
Date: Sat, 19 Jun 2010 14:32:04 +0200
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Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Frederic Weisbecker <fweisbec@gmail.com>, linux-kernel@vger.kernel.org,
       Greg KH <gregkh@suse.de>, Thomas Gleixner <tglx@linutronix.de>,
       Andrew Morton <akpm@linux-foundation.org>,
       John Kacur <jkacur@redhat.com>, Al Viro <viro@zeniv.linux.org.uk>,
       Ingo Molnar <mingo@elte.hu>
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On Friday 18 June 2010 22:25:22 Tony Luck wrote:
> On Fri, Jun 18, 2010 at 11:35 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> > Do you know if this was a problem with the original series or
> > something that got introduced by my last patch?
> 
> Problem was there before. Looks like it was not in next-20100616
> but began with next-20100617.

Ok, so it's certainly in one of the patches from Alan or me.

> > Also, if you don't mind, could you try if the problem also exists
> > with CONFIG_TTY_MUTEX enabled?
> With CONFIG_TTY_MUTEX=y kernel with both your patches builds
> and boots with no unusual messages.  Application output still gets
> garbled.

ok.
 
> > Which serial driver do you use?
> I boot with a "console=uart,io,0x3f8" argument, so I start out using
> 8250_early.c. Looks like it switched to 8250.c based on seeing
> this:
> 
> Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> 
> on the console log.

Good, so it's something I should be able to reproduce on a PC.

	Arnd