From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756971Ab2AJXK3 (ORCPT ); Tue, 10 Jan 2012 18:10:29 -0500 Received: from cantor2.suse.de ([195.135.220.15]:52684 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934314Ab2AJXC6 (ORCPT ); Tue, 10 Jan 2012 18:02:58 -0500 X-Mailbox-Line: From gregkh@clark.kroah.org Tue Jan 10 13:56:04 2012 Message-Id: <20120110215604.132676980@clark.kroah.org> User-Agent: quilt/0.50-25.1 Date: Tue, 10 Jan 2012 13:55:33 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Claudio Scordino , Dave Bender , Nicolas Ferre , Alan Cox Subject: [30/49] atmel_serial: fix spinlock lockup in RS485 code In-Reply-To: <20120110215609.GA22505@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Claudio Scordino commit dbf1115d3f8c7052788aa4e6e46abd27f3b3eeba upstream. Patch to fix a spinlock lockup in the driver that sometimes happens when the tasklet starts. Signed-off-by: Claudio Scordino Signed-off-by: Dave Bender Tested-by: Dave Bender Acked-by: Nicolas Ferre Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/atmel_serial.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -212,8 +212,9 @@ void atmel_config_rs485(struct uart_port { struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); unsigned int mode; + unsigned long flags; - spin_lock(&port->lock); + spin_lock_irqsave(&port->lock, flags); /* Disable interrupts */ UART_PUT_IDR(port, atmel_port->tx_done_mask); @@ -244,7 +245,7 @@ void atmel_config_rs485(struct uart_port /* Enable interrupts */ UART_PUT_IER(port, atmel_port->tx_done_mask); - spin_unlock(&port->lock); + spin_unlock_irqrestore(&port->lock, flags); }