Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752754Ab2HNWja (ORCPT ); Tue, 14 Aug 2012 18:39:30 -0400 Received: from ch1ehsobe004.messaging.microsoft.com ([216.32.181.184]:12536 "EHLO ch1outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751552Ab2HNWj1 (ORCPT ); Tue, 14 Aug 2012 18:39:27 -0400 X-Forefront-Antispam-Report: CIP:163.181.249.108;KIP:(null);UIP:(null);IPV:NLI;H:ausb3twp01.amd.com;RD:none;EFVD:NLI X-SpamScore: 0 X-BigFish: VPS0(zzzz1202hzz8275dhz2dh668h839hd24he5bhf0ah107ah) X-WSS-ID: 0M8RO9M-01-LYT-02 X-M-MSG: From: Jacob Shin To: X86-ML CC: LKML , Yinghai Lu , "H. Peter Anvin" , Andreas Herrmann , Tejun Heo , Borislav Petkov , Dave Young , Chao Wang , Vivek Goyal , Jacob Shin Subject: [PATCH V3 0/4] x86: Create direct mappings for E820_RAM only Date: Tue, 14 Aug 2012 17:39:13 -0500 Message-ID: <1344983957-4996-1-git-send-email-jacob.shin@amd.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 Content-Type: text/plain X-OriginatorOrg: amd.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1664 Lines: 42 Currently kernel direct mappings are created for all pfns between [ 0 to max_low_pfn ) and [ 4GB to max_pfn ). When we introduce memory holes, we end up mapping memory ranges that are not backed by physical DRAM. This is fine for lower memory addresses which can be marked as UC by fixed/variable range MTRRs, however we run in to trouble with high addresses. The following patchset creates direct mappings only for E820_RAM regions between 0 ~ max_low_pfn and 4GB ~ max_pfn. And leaves non-E820_RAM and memory holes unmapped. This third revision of the patchset attempts to resolve comments and concerns from the following threads: * https://lkml.org/lkml/2012/8/13/512 * https://lkml.org/lkml/2012/8/9/536 * https://lkml.org/lkml/2011/10/20/323 Jacob Shin (4): x86: Move enabling of PSE and PGE out of init_memory_mapping x86: find_early_table_space based on memory ranges that are being mapped x86: Only direct map addresses that are marked as E820_RAM x86: Fixup code testing if a pfn is direct mapped arch/x86/include/asm/page_types.h | 9 +++ arch/x86/kernel/cpu/amd.c | 6 +- arch/x86/kernel/setup.c | 121 +++++++++++++++++++++++++++++++------ arch/x86/mm/init.c | 74 +++++++++++------------ arch/x86/mm/init_64.c | 6 +- arch/x86/platform/efi/efi.c | 8 +-- 6 files changed, 155 insertions(+), 69 deletions(-) -- 1.7.9.5 -- 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/