From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 9 May 2002 20:13:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 9 May 2002 20:13:16 -0400 Received: from smtpzilla3.xs4all.nl ([194.109.127.139]:24073 "EHLO smtpzilla3.xs4all.nl") by vger.kernel.org with ESMTP id ; Thu, 9 May 2002 20:13:15 -0400 Message-ID: <3CDB108F.8B092095@linux-m68k.org> Date: Fri, 10 May 2002 02:13:03 +0200 From: Roman Zippel X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.4.18 i686) X-Accept-Language: en MIME-Version: 1.0 To: Daniel Phillips CC: Andrea Arcangeli , "Martin J. Bligh" , linux-kernel@vger.kernel.org Subject: Re: Bug: Discontigmem virt_to_page() [Alpha,ARM,Mips64?] In-Reply-To: <3CDAFF7C.57A59FB8@linux-m68k.org> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, Daniel Phillips wrote: > Show me where the 'physical' address is actually treated as a physical address. > You can't, because it isn't. The 'physical' address is merely a zero-based > logical address, and the code *relies* on it being contiguous. Most of the code doesn't care about physical addresses, because they either work with virtual memory or with the page structure. Physical addresses are only interesting to pass them to the hardware or to put them into the page table. > Your code is going to do __pa there, and you are going to go walking into places > you don't expect. Even you need my logical address space abstraction, or else you > want to go making global changes to the common kernel code that just add cruft. So far I've only seen a virtual address with some offset. You can maybe move that offset around, but you can't remove it. In the end it's the same. > I enjoy the feeling of removing cruft, even when it's an uphill battle. I'm happy to see patches. bye, Roman