Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754975AbbKLPlG (ORCPT ); Thu, 12 Nov 2015 10:41:06 -0500 Received: from mail-wm0-f44.google.com ([74.125.82.44]:34647 "EHLO mail-wm0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754892AbbKLPkg (ORCPT ); Thu, 12 Nov 2015 10:40:36 -0500 From: Matt Fleming To: Ingo Molnar , Thomas Gleixner , "H . Peter Anvin" Cc: Toshi Kani , Matt Fleming , linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, Borislav Petkov , Sai Praneeth Prakhya , Linus Torvalds , Dave Jones , Andrew Morton , Andy Lutomirski , Denys Vlasenko , Stephen Smalley Subject: [PATCH 6/6] Documentation/x86: Update EFI memory region description Date: Thu, 12 Nov 2015 15:40:23 +0000 Message-Id: <1447342823-3612-7-git-send-email-matt@codeblueprint.co.uk> X-Mailer: git-send-email 2.6.2 In-Reply-To: <1447342823-3612-1-git-send-email-matt@codeblueprint.co.uk> References: <1447342823-3612-1-git-send-email-matt@codeblueprint.co.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2502 Lines: 61 Make it clear that the EFI page tables are only available during EFI runtime calls since that subject has come up a fair numbers of times in the past. Additionally, add the EFI region start and end addresses to the table so that it's possible to see at a glance where they fall in relation to other regions. Cc: Borislav Petkov Cc: Sai Praneeth Prakhya Cc: Ingo Molnar Cc: Linus Torvalds Cc: Dave Jones Cc: Thomas Gleixner Cc: H. Peter Anvin Cc: Andrew Morton Cc: Andy Lutomirski Cc: Denys Vlasenko , Cc: Stephen Smalley Signed-off-by: Matt Fleming --- Documentation/x86/x86_64/mm.txt | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt index 05712ac83e38..a9885bb1ac22 100644 --- a/Documentation/x86/x86_64/mm.txt +++ b/Documentation/x86/x86_64/mm.txt @@ -16,6 +16,8 @@ ffffec0000000000 - fffffc0000000000 (=44 bits) kasan shadow memory (16TB) ... unused hole ... ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks ... unused hole ... +ffffffef00000000 - ffffffff00000000 (=64 GB) EFI region mapping space +... unused hole ... ffffffff80000000 - ffffffffa0000000 (=512 MB) kernel text mapping, from phys 0 ffffffffa0000000 - ffffffffff5fffff (=1525 MB) module mapping space ffffffffff600000 - ffffffffffdfffff (=8 MB) vsyscalls @@ -32,11 +34,9 @@ reference. Current X86-64 implementations only support 40 bits of address space, but we support up to 46 bits. This expands into MBZ space in the page tables. -->trampoline_pgd: - -We map EFI runtime services in the aforementioned PGD in the virtual -range of 64Gb (arbitrarily set, can be raised if needed) - -0xffffffef00000000 - 0xffffffff00000000 +We map EFI runtime services in the efi_pgd PGD in the virtual range of +64Gb (arbitrarily set, can be raised if needed). The mappings are not +part of any other kernel PGD and are only available during EFI runtime +calls. -Andi Kleen, Jul 2004 -- 2.6.2 -- 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/