Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757553AbYBGHcN (ORCPT ); Thu, 7 Feb 2008 02:32:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754315AbYBGHb6 (ORCPT ); Thu, 7 Feb 2008 02:31:58 -0500 Received: from rv-out-0910.google.com ([209.85.198.188]:59489 "EHLO rv-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751967AbYBGHb5 (ORCPT ); Thu, 7 Feb 2008 02:31:57 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:organization:to:subject:date:user-agent:cc:mime-version:content-disposition:content-type:content-transfer-encoding:message-id; b=gJhji4Q/cR6N/TxXB7e/1hX8jiuI5aV7K+bCbSjysf3KyK/AGcku5gsBbST2y6IoFUNN9l7Zg7mHU7xFN6ivwRdifEDg9fG4+cEMRZkEApB+F2J2KFb3xLKEqWix9X6EMuUEIhOnFZGn0UPSb9pC9BoVJfk61Dd3Tsq7P0IXfkE= From: Balaji Rao Organization: National Institute of Technology, Karnataka To: linux-kernel@vger.kernel.org Subject: [PATCH][Regression] x86, 32-bit: trim memory not covered by wb mtrrs - FIX Date: Thu, 7 Feb 2008 12:57:51 +0530 User-Agent: KMail/1.9.6 (enterprise 0.20071012.724442) Cc: Ingo Molnar , Thomas Gleixner , jesse.barnes@intel.com, yhlu.kernel@gmail.com, ak@suse.de, balajirrao@gmail.com MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Message-Id: <200802071257.51893.balajirrao@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2377 Lines: 71 Hello, The following commit caused my X server to stop working. commit 99fc8d424bc5d803fe92cad56c068fe64e73747a Author: Jesse Barnes Date: Wed Jan 30 13:33:18 2008 +0100 x86, 32-bit: trim memory not covered by wb mtrrs This patch fixes the improper handling of addresses > 4G by mtrr_trim_uncached_memory. This, now brings up X on my system. Signed-off-by: Balaji Rao diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index 1e27b69..b0f1d48 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -659,7 +659,7 @@ static __init int amd_special_default_mtrr(void) */ int __init mtrr_trim_uncached_memory(unsigned long end_pfn) { - unsigned long i, base, size, highest_addr = 0, def, dummy; + unsigned long i, base, size, highest_pfn = 0, def, dummy; mtrr_type type; u64 trim_start, trim_size; @@ -682,30 +682,27 @@ int __init mtrr_trim_uncached_memory(unsigned long end_pfn) mtrr_if->get(i, &base, &size, &type); if (type != MTRR_TYPE_WRBACK) continue; - base <<= PAGE_SHIFT; - size <<= PAGE_SHIFT; - if (highest_addr < base + size) - highest_addr = base + size; + if (highest_pfn < base + size) + highest_pfn = base + size; } /* kvm/qemu doesn't have mtrr set right, don't trim them all */ - if (!highest_addr) { + if (!highest_pfn) { printk(KERN_WARNING "WARNING: strange, CPU MTRRs all blank?\n"); WARN_ON(1); return 0; } - if ((highest_addr >> PAGE_SHIFT) < end_pfn) { + if (highest_pfn < end_pfn) { printk(KERN_WARNING "WARNING: BIOS bug: CPU MTRRs don't cover" " all of memory, losing %LdMB of RAM.\n", - (((u64)end_pfn << PAGE_SHIFT) - highest_addr) >> 20); + ((u64)(end_pfn - highest_pfn) << PAGE_SHIFT) >> 20); WARN_ON(1); printk(KERN_INFO "update e820 for mtrr\n"); - trim_start = highest_addr; - trim_size = end_pfn; - trim_size <<= PAGE_SHIFT; + trim_start = highest_pfn << PAGE_SHIFT; + trim_size = end_pfn << PAGE_SHIFT; trim_size -= trim_start; add_memory_region(trim_start, trim_size, E820_RESERVED); update_e820(); -- 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/