Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758137AbXEMHHe (ORCPT ); Sun, 13 May 2007 03:07:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757258AbXEMHH2 (ORCPT ); Sun, 13 May 2007 03:07:28 -0400 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:39440 "EHLO ebiederm.dsl.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755109AbXEMHH1 (ORCPT ); Sun, 13 May 2007 03:07:27 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: "Yinghai Lu" Cc: "Andi Kleen" , "Andrew Morton" , "Vivek Goyal" , "Linux Kernel Mailing List" Subject: Re: [PATCH]x86_64: build and use GDT on copied compressed kernel References: <86802c440705122233y327756e7te534199f46b2059d@mail.gmail.com> <86802c440705122329y27c6ef92v8cff43d52b99ae69@mail.gmail.com> <86802c440705122355r5f811d5bg2006b0b22ca885e6@mail.gmail.com> Date: Sun, 13 May 2007 01:06:51 -0600 In-Reply-To: <86802c440705122355r5f811d5bg2006b0b22ca885e6@mail.gmail.com> (Yinghai Lu's message of "Sat, 12 May 2007 23:55:34 -0700") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2512 Lines: 53 "Yinghai Lu" writes: > On 5/12/07, Eric W. Biederman wrote: >> >> For data segments we never use that GDT, it is only for the code >> segment we use the GDT and that only to get us into 64bit mode. >> > > after the patch > linux:/home/yhlu/xx/xx/kernel/linux-2.6/arch/x86_64/boot/compressed # > readelf -e vmlinux > ... > Section Headers: > [Nr] Name Type Address Offset > Size EntSize Flags Link Info Align > [ 0] NULL 0000000000000000 00000000 > 0000000000000000 0000000000000000 0 0 0 > [ 1] .text PROGBITS 0000000000000000 00100000 > 000000000032617c 0000000000000000 AX 0 0 16 > [ 2] .rodata PROGBITS 0000000000326180 00426180 > 0000000000000400 0000000000000000 A 0 0 32 > [ 3] .eh_frame PROGBITS 0000000000326580 00426580 > 0000000000000210 0000000000000000 A 0 0 8 > [ 4] .data PROGBITS 0000000000326790 00426790 > 0000000000000008 0000000000000000 WA 0 0 8 > [ 5] .bss NOBITS 00000000003267a0 00426798 > 000000000000b860 0000000000000000 WA 0 0 32 > [ 6] .comment PROGBITS 0000000000000000 00426798 > 0000000000000035 0000000000000000 0 0 1 > [ 7] .shstrtab STRTAB 0000000000000000 004267cd > 0000000000000047 0000000000000000 0 0 1 > [ 8] .symtab SYMTAB 0000000000000000 00426a98 > 00000000000007c8 0000000000000018 9 60 8 > [ 9] .strtab STRTAB 0000000000000000 00427260 > 0000000000000350 0000000000000000 0 0 1 > Key to Flags: > W (write), A (alloc), X (execute), M (merge), S (strings) > I (info), L (link order), G (group), x (unknown) > O (extra OS processing required) o (OS specific), p (processor specific) > > after the patch, it seems .data section size still have 8 bytes. > before that will 0x28. > don't know what are the 8 bytes. Probably variables in misc.c Eric - 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/