From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753014Ab0ETAJH (ORCPT ); Wed, 19 May 2010 20:09:07 -0400 Received: from rcsinet10.oracle.com ([148.87.113.121]:23435 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752467Ab0ETAJE (ORCPT ); Wed, 19 May 2010 20:09:04 -0400 Message-ID: <4BF47D25.8060209@oracle.com> Date: Wed, 19 May 2010 17:07:01 -0700 From: Yinghai User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100317 SUSE/3.0.4-1.1.1 Thunderbird/3.0.4 MIME-Version: 1.0 To: Mathieu Rondonneau CC: "H. Peter Anvin" , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Ingo Molnar , Linus Torvalds Subject: Re: [PATCH] Prevent reserving RAM in the region already reserved by BIOS References: <4BF42296.1030905@oracle.com> <4BF4235D.3080904@zytor.com> <4BF46D9B.4090806@zytor.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Auth-Type: Internal IP X-Source-IP: rcsinet13.oracle.com [148.87.113.125] X-CT-RefId: str=0001.0A090201.4BF47D77.00DE:SCFMA4539811,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/19/2010 05:01 PM, Mathieu Rondonneau wrote: > it' s not in ISA space. > once loading the NVIDIA driver, the warnign oops shows up. > 4K starting at 0x9f800 (i.e. to 0xa007ff) overlap with the ISA space > (starting at 0xa0000). > > When I don' t load the driver, no oops. > So I am assuming nvidia driver request 4K of memory, that happens to > be available in the bios area. > > I think that there is a check missing somewhere to report that > available RAM buffer is already reserved (by BIOS) so we need to get > it from somewhere else. please check if this patch fix the problem. Subject: [PATCH] x86: Align e820 ram range to page To workaround wrong BIOS memory map. Signed-off-by: Yinghai Lu --- arch/x86/kernel/e820.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) Index: linux-2.6/arch/x86/kernel/e820.c =================================================================== --- linux-2.6.orig/arch/x86/kernel/e820.c +++ linux-2.6/arch/x86/kernel/e820.c @@ -910,6 +910,47 @@ static int __init parse_memmap_opt(char } early_param("memmap", parse_memmap_opt); +static void __init e820_align_ram_page(void) +{ + int i; + bool changed = false;; + + for (i = 0; i < e820.nr_map; i++) { + struct e820entry *entry = &e820.map[i]; + u64 start, end; + u64 start_aligned, end_aligned; + + if (entry->type != E820_RAM) + continue; + + start = entry->addr; + end = start + entry->size; + + start_aligned = round_up(start, PAGE_SIZE); + end_aligned = round_down(end, PAGE_SIZE); + + if (end_aligned <= start_aligned) { + e820_update_range(start, end - start, E820_RAM, E820_RESERVED); + changed = true; + continue; + } + if (start < start_aligned) { + e820_update_range(start, start_aligned - start, E820_RAM, E820_RESERVED); + changed = true; + } + if (end_aligned < end) { + e820_update_range(end_aligned, end - end_aligned, E820_RAM, E820_RESERVED); + changed = true; + } + } + + if (changed) { + sanitize_e820_map(); + printk(KERN_INFO "aligned physical RAM map:\n"); + e820_print_map("aligned"); + } +} + void __init finish_e820_parsing(void) { if (userdef) { @@ -922,6 +963,9 @@ void __init finish_e820_parsing(void) printk(KERN_INFO "user-defined physical RAM map:\n"); e820_print_map("user"); } + + /* In case, We have RAM entres that are not PAGE aligned */ + e820_align_ram_page(); } static inline const char *e820_type_to_string(int e820_type)