From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Fri, 06 Apr 2018 03:34:48 +0200 (CEST) Received: from smtp.codeaurora.org ([198.145.29.96]:52710 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23994626AbeDFBelTL6Xd (ORCPT ); Fri, 6 Apr 2018 03:34:41 +0200 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 766806081B; Fri, 6 Apr 2018 01:34:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1522978474; bh=34v6SXWpP8Vzfv7iQcsdoIDgGYEUWjUInnSMnkoV26w=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=iWdOw430WazP1Set4sfbNgX1jgTTj7OvQCxQmpN4yGVlXYOkrMQmPQ+XMBonSmwFY NbccUnwyJOX7R/CMzOqGdB8Hvg/Zg54Ks5jPMULHOwN7yB8pd+93UHepOJwtWlLaec I0wrmFq1y/x3fS0QVTPT1Lcxk7ZLSKc/0GfRnXoc= Received: from [192.168.0.105] (cpe-174-109-247-98.nc.res.rr.com [174.109.247.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: okaya@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id B79DA60274; Fri, 6 Apr 2018 01:34:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1522978473; bh=34v6SXWpP8Vzfv7iQcsdoIDgGYEUWjUInnSMnkoV26w=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=KOy+EwgeXu0X83sPVFmcur52Ybfs9rjEfEw5I0I+oEAfGLJf9GX8lOSvuqWXJsCxZ +qjKl9E+mGprTaetmUiNVFbKAlSILNnh+qLQWucJzxKiurx9ucIz6AlgPIhVf19Fsh SJT5rR1tdUEwp5tpg7WfKmW9BpuNA8j/gBs0+Tqw= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org B79DA60274 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=okaya@codeaurora.org Subject: Re: [PATCH v3 2/2] MIPS: io: add a barrier after register read in readX() To: linux-mips@linux-mips.org, arnd@arndb.de, timur@codeaurora.org, sulrich@codeaurora.org Cc: linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Ralf Baechle , James Hogan , Paul Burton , linux-kernel@vger.kernel.org References: <1522760109-16497-1-git-send-email-okaya@codeaurora.org> <1522760109-16497-2-git-send-email-okaya@codeaurora.org> From: Sinan Kaya Message-ID: <41e184ae-689e-93c9-7b15-0c68bd624130@codeaurora.org> Date: Thu, 5 Apr 2018 21:34:31 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <1522760109-16497-2-git-send-email-okaya@codeaurora.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 63420 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: okaya@codeaurora.org Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips On 4/3/2018 8:55 AM, Sinan Kaya wrote: > While a barrier is present in writeX() function before the register write, > a similar barrier is missing in the readX() function after the register > read. This could allow memory accesses following readX() to observe > stale data. > > Signed-off-by: Sinan Kaya > Reported-by: Arnd Bergmann > --- > arch/mips/include/asm/io.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h > index fd00ddaf..6ac502f 100644 > --- a/arch/mips/include/asm/io.h > +++ b/arch/mips/include/asm/io.h > @@ -377,6 +377,7 @@ static inline type pfx##read##bwlq(const volatile void __iomem *mem) \ > BUG(); \ > } \ > \ > + rmb(); \ > return pfx##ioswab##bwlq(__mem, __val); \ > } > > Can we get these merged to 4.17? There was a consensus to fix the architectures having API violation issues. https://www.mail-archive.com/netdev@vger.kernel.org/msg225971.html -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.