From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sinan Kaya Subject: Re: [PATCH v3 2/2] MIPS: io: add a barrier after register read in readX() Date: Fri, 6 Apr 2018 14:15:57 -0400 Message-ID: References: <1522760109-16497-1-git-send-email-okaya@codeaurora.org> <1522760109-16497-2-git-send-email-okaya@codeaurora.org> <41e184ae-689e-93c9-7b15-0c68bd624130@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <41e184ae-689e-93c9-7b15-0c68bd624130@codeaurora.org> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org 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 List-Id: linux-arm-msm@vger.kernel.org On 4/5/2018 9:34 PM, Sinan Kaya wrote: > 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 > > Any news on the MIPS front? Is this something that Arnd can merge? or does it have to go through the MIPS tree. It feels like the MIPS is dead since nobody replied to me in the last few weeks on a very important topic. -- 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. From mboxrd@z Thu Jan 1 00:00:00 1970 From: okaya@codeaurora.org (Sinan Kaya) Date: Fri, 6 Apr 2018 14:15:57 -0400 Subject: [PATCH v3 2/2] MIPS: io: add a barrier after register read in readX() In-Reply-To: <41e184ae-689e-93c9-7b15-0c68bd624130@codeaurora.org> References: <1522760109-16497-1-git-send-email-okaya@codeaurora.org> <1522760109-16497-2-git-send-email-okaya@codeaurora.org> <41e184ae-689e-93c9-7b15-0c68bd624130@codeaurora.org> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 4/5/2018 9:34 PM, Sinan Kaya wrote: > 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 at vger.kernel.org/msg225971.html > > Any news on the MIPS front? Is this something that Arnd can merge? or does it have to go through the MIPS tree. It feels like the MIPS is dead since nobody replied to me in the last few weeks on a very important topic. -- 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.