Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932349Ab0GASk6 (ORCPT ); Thu, 1 Jul 2010 14:40:58 -0400 Received: from kroah.org ([198.145.64.141]:40533 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757905Ab0GASXd (ORCPT ); Thu, 1 Jul 2010 14:23:33 -0400 X-Mailbox-Line: From gregkh@clark.site Thu Jul 1 10:32:13 2010 Message-Id: <20100701173212.951098396@clark.site> User-Agent: quilt/0.48-10.1 Date: Thu, 01 Jul 2010 10:31:39 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Marek Vasut , Russell King Subject: [patch 073/149] ARM: 6146/1: sa1111: Prevent deadlock in resume path In-Reply-To: <20100701175144.GA2116@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1939 Lines: 61 2.6.32-stable review patch. If anyone has any objections, please let us know. ------------------ From: =?UTF-8?q?Marek=20Va=C5=A1ut?= commit 3defb2476166445982a90c12d33f8947e75476c4 upstream. This patch reorganises the sa1111_resume() function in a manner the spinlock happens after calling the sa1111_wake(). This fixes two bugs: 1) This function called sa1111_wake() which tried to claim the same spinlock the sa1111_resume() already claimed. This would result in certain deadlock. Original idea for this part: Russell King 2) The function didn't unlock the spinlock in case the chip didn't report correct ID. Original idea for this part: Julia Lawall Signed-off-by: Marek Vasut Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman --- arch/arm/common/sa1111.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/arch/arm/common/sa1111.c +++ b/arch/arm/common/sa1111.c @@ -887,8 +887,6 @@ static int sa1111_resume(struct platform if (!save) return 0; - spin_lock_irqsave(&sachip->lock, flags); - /* * Ensure that the SA1111 is still here. * FIXME: shouldn't do this here. @@ -905,6 +903,13 @@ static int sa1111_resume(struct platform * First of all, wake up the chip. */ sa1111_wake(sachip); + + /* + * Only lock for write ops. Also, sa1111_wake must be called with + * released spinlock! + */ + spin_lock_irqsave(&sachip->lock, flags); + sa1111_writel(0, sachip->base + SA1111_INTC + SA1111_INTEN0); sa1111_writel(0, sachip->base + SA1111_INTC + SA1111_INTEN1); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/