From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5BDE4C3A5A0 for ; Mon, 20 Apr 2020 14:55:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 38C8020775 for ; Mon, 20 Apr 2020 14:55:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="iDbMYWuE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728912AbgDTOz5 (ORCPT ); Mon, 20 Apr 2020 10:55:57 -0400 Received: from mail27.static.mailgun.info ([104.130.122.27]:62390 "EHLO mail27.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725944AbgDTOz4 (ORCPT ); Mon, 20 Apr 2020 10:55:56 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1587394556; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=7MhmolhOBg+potQk9sjLeyxXiHqBAvP6Cxd5Xrm2ty4=; b=iDbMYWuEUd9rBgcUKpFGYdbHV7LJNkOmxswH5RU7wsqpukzaQPkJ/pz4zVGcRRslOaP1VE72 PAo0Vy5Znp6aGHp2xe5zVbXm7xLYCc+vSwND0YD9exEC+fUdstD8oQyZZJDVwpFld43Akd16 mflHfy6jCt0Bex0OEClIBMNTYI4= X-Mailgun-Sending-Ip: 104.130.122.27 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by mxa.mailgun.org with ESMTP id 5e9db7ef.7f8e566372d0-smtp-out-n04; Mon, 20 Apr 2020 14:55:43 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 9C0B8C433F2; Mon, 20 Apr 2020 14:55:42 +0000 (UTC) Received: from congzhan-gv.qualcomm.com (unknown [180.166.53.21]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: congzhan) by smtp.codeaurora.org (Postfix) with ESMTPSA id CE7D4C433D2; Mon, 20 Apr 2020 14:55:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org CE7D4C433D2 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=none smtp.mailfrom=congzhan@codeaurora.org From: Cong Zhang To: Russell King Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Cong Zhang Subject: [PATCH] ARM: align the start and end of v7_setup_stack to cache line Date: Mon, 20 Apr 2020 22:50:35 +0800 Message-Id: <1587394235-24008-1-git-send-email-congzhan@codeaurora.org> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The v7_setup_stack is used when D-cache disabled. When CPU is reading something nearby with D-cache enabled. It is possible to read v7_setup_stack to cache line. There is a risk that when cache line write back the data, v7_setup_stack may already been modified by other CPU with D-cache disabled. The change make v7_setup_stack align cache line size and use the whole cache line to prevent corrupting v7_setup_stack. Signed-off-by: Cong Zhang --- arch/arm/mm/proc-v7.S | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index 339eb17..587e2eb 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -18,6 +18,7 @@ #include #include #include +#include #include "proc-macros.S" @@ -548,10 +549,10 @@ __v7_setup_stack_ptr: ENDPROC(__v7_setup) .bss - .align 2 + .align L1_CACHE_SHIFT __v7_setup_stack: .space 4 * 7 @ 7 registers - + .align L1_CACHE_SHIFT __INITDATA .weak cpu_v7_bugs_init -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project