Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755883Ab0KXTIz (ORCPT ); Wed, 24 Nov 2010 14:08:55 -0500 Received: from hqemgate03.nvidia.com ([216.228.121.140]:15488 "EHLO hqemgate03.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754748Ab0KXTIy (ORCPT ); Wed, 24 Nov 2010 14:08:54 -0500 X-PGP-Universal: processed; by hqnvupgp05.nvidia.com on Wed, 24 Nov 2010 11:04:20 -0800 From: James Jones Organization: NVIDIA To: Nicolas Pitre Subject: Re: [PATCH] ARM: Fix find_next_zero_bit and related assembly Date: Wed, 24 Nov 2010 11:08:47 -0800 User-Agent: KMail/1.13.3 (Linux/2.6.33.4; KDE/4.4.3; x86_64; ; ) Cc: Stephen Boyd , Russell King , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" References: <1289524615-22484-1-git-send-email-jajones@nvidia.com> <4CED55A6.5090608@codeaurora.org> In-Reply-To: X-NVConfidentiality: public MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201011241108.47776.jajones@nvidia.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1666 Lines: 42 On Wednesday 24 November 2010 11:00:12 am Nicolas Pitre wrote: > On Wed, 24 Nov 2010, Stephen Boyd wrote: > > On 11/23/2010 03:28 PM, James Jones wrote: > > > On Tuesday 23 November 2010 13:26:47 Nicolas Pitre wrote: > > >> On Thu, 11 Nov 2010, James Jones wrote: > > >>> The find_next_bit, find_first_bit, find_next_zero_bit > > >>> and find_first_zero_bit functions were not properly > > >>> clamping to the maxbit argument at the bit level. They > > >>> were instead only checking maxbit at the byte level. > > >>> To fix this, add a compare and a conditional move > > >>> instruction to the end of the common bit-within-the- > > >>> byte code used by all the functions and be sure not to > > >>> clobber the maxbit argument before it is used. > > >>> > > >>> Signed-off-by: James Jones > > >>> Tested-by: Stephen Warren > > >> > > >> Reviewed-by: Nicolas Pitre > > >> > > >> Please send to RMK's patch system. > > > > > > Thanks for the review. It's already in the patch system, but I updated > > > the entry to include your reviewed-by line. > > > > Should this be sent to the stable tree too? > > It could, yes. This is hardly an urgent fix though, as the bug has been > there virtually forever. > > > Nicolas While ancient, it does cause per-cpu allocations to fail in some situations, which generally causes panics. Thanks, -James -- 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/