Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755949Ab0KXTNM (ORCPT ); Wed, 24 Nov 2010 14:13:12 -0500 Received: from relais.videotron.ca ([24.201.245.36]:17519 "EHLO relais.videotron.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754006Ab0KXTNL (ORCPT ); Wed, 24 Nov 2010 14:13:11 -0500 MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: TEXT/PLAIN; charset=US-ASCII Date: Wed, 24 Nov 2010 14:13:05 -0500 (EST) From: Nicolas Pitre X-X-Sender: nico@xanadu.home To: James Jones Cc: Stephen Boyd , Russell King , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH] ARM: Fix find_next_zero_bit and related assembly In-reply-to: <201011241108.47776.jajones@nvidia.com> Message-id: References: <1289524615-22484-1-git-send-email-jajones@nvidia.com> <4CED55A6.5090608@codeaurora.org> <201011241108.47776.jajones@nvidia.com> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1831 Lines: 46 On Wed, 24 Nov 2010, James Jones wrote: > 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. That would be a good justification for the stable tree then. Nicolas -- 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/