From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19313 invoked by alias); 10 Mar 2005 06:59:13 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 19238 invoked from network); 10 Mar 2005 06:59:07 -0000 Received: from unknown (HELO ebiederm.dsl.xmission.com) (166.70.28.69) by sourceware.org with SMTP; 10 Mar 2005 06:59:07 -0000 Received: from ebiederm.dsl.xmission.com (localhost [127.0.0.1]) by ebiederm.dsl.xmission.com (8.12.3/8.12.3/Debian-7.1) with ESMTP id j2A6u99N021324; Wed, 9 Mar 2005 23:56:09 -0700 Received: (from eric@localhost) by ebiederm.dsl.xmission.com (8.12.3/8.12.3/Debian-7.1) id j2A6u4uI021321; Wed, 9 Mar 2005 23:56:04 -0700 X-Authentication-Warning: ebiederm.dsl.xmission.com: eric set sender to ebiederm@xmission.com using -f To: Vivek Goyal Cc: Andrew Morton , gdb , Dave Anderson , lkml , fastboot Subject: Re: [Fastboot] Re: Query: Kdump: Core Image ELF Format References: <1110286210.4195.27.camel@wks126478wss.in.ibm.com> <1110350629.31878.7.camel@wks126478wss.in.ibm.com> <1110430955.3574.11.camel@wks126478wss.in.ibm.com> From: ebiederm@xmission.com (Eric W. Biederman) Date: Thu, 10 Mar 2005 06:59:00 -0000 In-Reply-To: <1110430955.3574.11.camel@wks126478wss.in.ibm.com> Message-ID: User-Agent: Gnus/5.0808 (Gnus v5.8.8) Emacs/21.2 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SW-Source: 2005-03/txt/msg00092.txt.bz2 Vivek Goyal writes: > I want to fill the virtual addresses of linearly mapped region. That is > physical addresses from 0 to MAXMEM (896 MB) are mapped by kernel at > virtual addresses PAGE_OFFSET to (PAGE_OFFSET + MAXMEM). Values of > PAGE_OFFSET and MAXMEM are already known and hard-coded. PAGE_OFFSET has a common value of 0xc0000000, on x86. However that value is by no means fixed. The 4G/4G split changes it as do some other patches floating around at the time. On x86-64 I don't know how stable those kinds of offsets are. > I think I used the terminology kernel virtual address and that is adding > to the confusion. Kernel virtual addresses are not necessarily linearly > mapped. What I meant was kernel logical addresses whose associated > physical addresses differ only by a constant offset. I know what you meant. I simply meant that things don't look that constant to me. Especially in Linux where there are enough people to try most of the reasonable possibilities. I don't even think it is a bad idea. But I do think we have a different idea of what is constant. Eric