From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 7 Jun 2001 11:00:33 +0100 From: "Stephen C. Tweedie" Subject: Re: temp. mem mappings Message-ID: <20010607110033.Q1757@redhat.com> References: <3B2C3149@MailAndNews.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3B2C3149@MailAndNews.com>; from cohutta@MailAndNews.com on Wed, Jun 06, 2001 at 05:14:26PM -0400 Sender: owner-linux-mm@kvack.org Return-Path: To: cohutta Cc: "Stephen C. Tweedie" , linux-mm List-ID: Hi, On Wed, Jun 06, 2001 at 05:14:26PM -0400, cohutta wrote: > I think this is part of the problem: on my 1 GB system, the > ACPI tables are at physical 0x3fffxxxx == virtual 0xffffxxxx, > which could conflict with the APIC and IOAPIC mappings > (from fixmap.h). Shouldn't be --- the fixmaps should be part of the kernel's dynamic virtual area, which is not identity mapped. You can still map those physical addresses via kmap() on a highmem system (and a 1GB machine should be running a highmem kernel). > Well, i'm talking about physical memory, but it's marked as ACPI > data. If it is marked PG_Reserved, then ioremap() will work on it despite it being inside the normal physical memory area. If not, kmap() will still work. > Another part of the problem is that I need to do this early in > arch/i386/kernel/setup.c::setup_arch(), like between calls to > paging_init() and init_apic_mappings(). I can't use ioremap() > here can i? ioremap() calls get_vm_area() which calls > kmalloc(), and i don't think i can use kmalloc() just yet. Right --- you can use alloc_pages but we haven't done the initialisation of the kmalloc slabsl by this point. _Why_ do you need access to the ACPI tables so early, though? Cheers, Stephen -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/