From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757744AbYACP3e (ORCPT ); Thu, 3 Jan 2008 10:29:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754566AbYACPYj (ORCPT ); Thu, 3 Jan 2008 10:24:39 -0500 Received: from mx2.suse.de ([195.135.220.15]:43026 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754360AbYACPYe (ORCPT ); Thu, 3 Jan 2008 10:24:34 -0500 From: Andi Kleen References: <20080103424.989432000@suse.de> In-Reply-To: <20080103424.989432000@suse.de> To: linux-kernel@vger.kernel.org Subject: [PATCH CPA] [18/28] CPA: Make change_page_attr() more robust against use of PAT bits Message-Id: <20080103152433.22C3F14E23@wotan.suse.de> Date: Thu, 3 Jan 2008 16:24:33 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use the page table level instead of the PSE bit to check if the PTE is for a 4K page or not. This makes the code more robust when the PAT bit is changed because the PAT bit on 4K pages is in the same position as the PSE bit. Signed-off-by: Andi Kleen --- arch/x86/mm/pageattr_32.c | 4 ++-- arch/x86/mm/pageattr_64.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) Index: linux/arch/x86/mm/pageattr_32.c =================================================================== --- linux.orig/arch/x86/mm/pageattr_32.c +++ linux/arch/x86/mm/pageattr_32.c @@ -209,7 +209,7 @@ __change_page_attr(struct page *page, pg set_tlb_flush(address); if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL)) { - if (!pte_huge(*kpte)) { + if (level == 3) { set_pte_atomic(kpte, mk_pte(page, prot)); } else { pgprot_t ref_prot; @@ -225,7 +225,7 @@ __change_page_attr(struct page *page, pg kpte_page = split; } page_private(kpte_page)++; - } else if (!pte_huge(*kpte)) { + } else if (level == 3) { set_pte_atomic(kpte, mk_pte(page, PAGE_KERNEL)); BUG_ON(page_private(kpte_page) == 0); page_private(kpte_page)--; Index: linux/arch/x86/mm/pageattr_64.c =================================================================== --- linux.orig/arch/x86/mm/pageattr_64.c +++ linux/arch/x86/mm/pageattr_64.c @@ -184,7 +184,7 @@ __change_page_attr(unsigned long address set_tlb_flush(address); if (pgprot_val(prot) != pgprot_val(ref_prot)) { - if (!pte_huge(*kpte)) { + if (level == 4) { set_pte(kpte, pfn_pte(pfn, prot)); } else { /* @@ -201,7 +201,7 @@ __change_page_attr(unsigned long address kpte_page = split; } page_private(kpte_page)++; - } else if (!pte_huge(*kpte)) { + } else if (level == 4) { set_pte(kpte, pfn_pte(pfn, ref_prot)); BUG_ON(page_private(kpte_page) == 0); page_private(kpte_page)--;