Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757329Ab0KLBR1 (ORCPT ); Thu, 11 Nov 2010 20:17:27 -0500 Received: from hqemgate04.nvidia.com ([216.228.121.35]:6215 "EHLO hqemgate04.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754001Ab0KLBR0 (ORCPT ); Thu, 11 Nov 2010 20:17:26 -0500 X-PGP-Universal: processed; by hqnvupgp04.nvidia.com on Thu, 11 Nov 2010 17:17:25 -0800 From: James Jones To: Russell King Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, James Jones Subject: [PATCH] ARM: Fix find_next_zero_bit and related assembly Date: Thu, 11 Nov 2010 17:16:55 -0800 Message-Id: <1289524615-22484-1-git-send-email-jajones@nvidia.com> X-Mailer: git-send-email 1.7.1 X-NVConfidentiality: public X-OriginalArrivalTime: 12 Nov 2010 01:17:20.0096 (UTC) FILETIME=[5A43B600:01CB8207] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1383 Lines: 46 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 --- arch/arm/lib/findbit.S | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/arm/lib/findbit.S b/arch/arm/lib/findbit.S index 1e4cbd4..64f6bc1 100644 --- a/arch/arm/lib/findbit.S +++ b/arch/arm/lib/findbit.S @@ -174,8 +174,8 @@ ENDPROC(_find_next_bit_be) */ .L_found: #if __LINUX_ARM_ARCH__ >= 5 - rsb r1, r3, #0 - and r3, r3, r1 + rsb r0, r3, #0 + and r3, r3, r0 clz r3, r3 rsb r3, r3, #31 add r0, r2, r3 @@ -190,5 +190,7 @@ ENDPROC(_find_next_bit_be) addeq r2, r2, #1 mov r0, r2 #endif + cmp r1, r0 @ Clamp to maxbit + movlo r0, r1 mov pc, lr -- 1.7.1 -- 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/