From mboxrd@z Thu Jan  1 00:00:00 1970
From: ben-linux@fluff.org (Ben Dooks)
Date: Fri, 13 Nov 2009 10:57:34 +0000
Subject: [PATCH] serial21285: fix disable_irq-from-interrupt-handler
	deadlock
In-Reply-To: <20091113090234.7d028820@marrow.netinsight.se>
References: <20091113090234.7d028820@marrow.netinsight.se>
Message-ID: <20091113105734.GM4808@trinity.fluff.org>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Fri, Nov 13, 2009 at 09:02:34AM +0100, Simon Kagstrom wrote:
> The console hangs during bootup when disable_irq is called from the
> transmit interrupt handler (it will wait forever for it's "own"
> interrupt in synchronize_irq). Fix by using disable_irq_nosync()
> instead.
> 
> Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
Acked-by: Ben Dooks <ben@simtec.co.uk>
> ---
> Russell: This patch is a bit of RFC since I'm not quite sure that it's the correct
> solution. It unbreaks booting on our footbridge-based platform. Let me
> know if I should look at other solutions!
> 
>  drivers/serial/21285.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/serial/21285.c b/drivers/serial/21285.c
> index 1e3d193..8681f13 100644
> --- a/drivers/serial/21285.c
> +++ b/drivers/serial/21285.c
> @@ -58,7 +58,7 @@ static const char serial21285_name[] = "Footbridge UART";
>  static void serial21285_stop_tx(struct uart_port *port)
>  {
>  	if (tx_enabled(port)) {
> -		disable_irq(IRQ_CONTX);
> +		disable_irq_nosync(IRQ_CONTX);
>  		tx_enabled(port) = 0;
>  	}
>  }
> @@ -74,7 +74,7 @@ static void serial21285_start_tx(struct uart_port *port)
>  static void serial21285_stop_rx(struct uart_port *port)
>  {
>  	if (rx_enabled(port)) {
> -		disable_irq(IRQ_CONRX);
> +		disable_irq_nosync(IRQ_CONRX);
>  		rx_enabled(port) = 0;
>  	}
>  }
> -- 
> 1.6.0.4
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

-- 
-- 
Ben

Q:      What's a light-year?
A:      One-third less calories than a regular year.