Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758950AbcCDPJG (ORCPT ); Fri, 4 Mar 2016 10:09:06 -0500 Received: from bes.se.axis.com ([195.60.68.10]:48929 "EHLO bes.se.axis.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752387AbcCDPJE convert rfc822-to-8bit (ORCPT ); Fri, 4 Mar 2016 10:09:04 -0500 From: Lars Persson To: Paul Burton CC: "linux-mips@linux-mips.org" , Ralf Baechle , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 1/4] MIPS: Flush dcache for flush_kernel_dcache_page Thread-Topic: [PATCH 1/4] MIPS: Flush dcache for flush_kernel_dcache_page Thread-Index: AQHRc2N2P9HTweD4gUC06+JPi1vOcJ9JaMnV Date: Fri, 4 Mar 2016 15:09:00 +0000 Message-ID: References: <1456799879-14711-1-git-send-email-paul.burton@imgtec.com>,<1456799879-14711-2-git-send-email-paul.burton@imgtec.com> In-Reply-To: <1456799879-14711-2-git-send-email-paul.burton@imgtec.com> Accept-Language: en-US Content-Language: sv-SE X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1373 Lines: 38 > 1 mars 2016 kl. 03:38 Paul Burton : > > The flush_kernel_dcache_page function was previously essentially a nop. > This is incorrect for MIPS, where if a page has been modified & either > it aliases or it's executable & the icache doesn't fill from dcache then > the content needs to be written back from dcache to the next level of > the cache hierarchy (which is shared with the icache). > > Implement this by simply calling flush_dcache_page, treating this > kmapped cache flush function (flush_kernel_dcache_page) exactly the same > as its non-kmapped counterpart (flush_dcache_page). > > Signed-off-by: Paul Burton > --- > > arch/mips/include/asm/cacheflush.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/mips/include/asm/cacheflush.h b/arch/mips/include/asm/cacheflush.h > index 723229f..7e9f468 100644 > --- a/arch/mips/include/asm/cacheflush.h > +++ b/arch/mips/include/asm/cacheflush.h > @@ -132,6 +132,7 @@ static inline void kunmap_noncoherent(void) > static inline void flush_kernel_dcache_page(struct page *page) > { > BUG_ON(cpu_has_dc_aliases && PageHighMem(page)); > + flush_dcache_page(page); Should we use instead __flush_dcache_page() that flushes immediately for mapped pages ? Steven J Hill's old patch set for highmem had done it like this. > } > > /* > -- > 2.7.1 >