Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753000AbaKCTXr (ORCPT ); Mon, 3 Nov 2014 14:23:47 -0500 Received: from g4t3427.houston.hp.com ([15.201.208.55]:8011 "EHLO g4t3427.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752128AbaKCTXn (ORCPT ); Mon, 3 Nov 2014 14:23:43 -0500 Message-ID: <1415041782.10958.26.camel@misato.fc.hp.com> Subject: Re: [PATCH v4 5/7] x86, mm, pat: Refactor !pat_enabled handling From: Toshi Kani To: Thomas Gleixner Cc: hpa@zytor.com, mingo@redhat.com, akpm@linux-foundation.org, arnd@arndb.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org, jgross@suse.com, stefan.bader@canonical.com, luto@amacapital.net, hmh@hmh.eng.br, yigal@plexistor.com, konrad.wilk@oracle.com Date: Mon, 03 Nov 2014 12:09:42 -0700 In-Reply-To: References: <1414450545-14028-1-git-send-email-toshi.kani@hp.com> <1414450545-14028-6-git-send-email-toshi.kani@hp.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4 (3.10.4-4.fc20) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2014-11-03 at 20:01 +0100, Thomas Gleixner wrote: > On Mon, 27 Oct 2014, Toshi Kani wrote: > > diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c > > index ee58a0b..96aa8bf 100644 > > --- a/arch/x86/mm/iomap_32.c > > +++ b/arch/x86/mm/iomap_32.c > > @@ -70,29 +70,23 @@ void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot) > > return (void *)vaddr; > > } > > > > -/* > > - * Map 'pfn' using protections 'prot' > > - */ > > -#define __PAGE_KERNEL_WC (__PAGE_KERNEL | \ > > - cachemode2protval(_PAGE_CACHE_MODE_WC)) > > - > > void __iomem * > > iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot) > > { > > /* > > - * For non-PAT systems, promote PAGE_KERNEL_WC to PAGE_KERNEL_UC_MINUS. > > - * PAGE_KERNEL_WC maps to PWT, which translates to uncached if the > > - * MTRR is UC or WC. UC_MINUS gets the real intention, of the > > - * user, which is "WC if the MTRR is WC, UC if you can't do that." > > + * For non-PAT systems, translate non-WB request to UC- just in > > + * case the caller set the PWT bit to prot directly without using > > + * pgprot_writecombine(). UC- translates to uncached if the MTRR > > + * is UC or WC. UC- gets the real intention, of the user, which is > > + * "WC if the MTRR is WC, UC if you can't do that." > > */ > > - if (!pat_enabled && pgprot_val(prot) == __PAGE_KERNEL_WC) > > + if (!pat_enabled && pgprot2cachemode(prot) != _PAGE_CACHE_MODE_WB) > > prot = __pgprot(__PAGE_KERNEL | > > cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS)); > > > > return (void __force __iomem *) kmap_atomic_prot_pfn(pfn, prot); > > } > > EXPORT_SYMBOL_GPL(iomap_atomic_prot_pfn); > > -#undef __PAGE_KERNEL_WC > > Rejects. Please update against Juergens latest. Yes, I have addressed this merge conflict in my next version. I will submit it shortly after all other comments are addressed. :-) Thanks, -Toshi -- 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/