Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753518Ab0HZAOW (ORCPT ); Wed, 25 Aug 2010 20:14:22 -0400 Received: from hera.kernel.org ([140.211.167.34]:57081 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752400Ab0HZAOT (ORCPT ); Wed, 25 Aug 2010 20:14:19 -0400 Date: Thu, 26 Aug 2010 00:12:46 GMT From: "tip-bot for H. Peter Anvin" Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, akpm@linux-foundation.org, tglx@linutronix.de, hpa@linux.intel.com Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, tglx@linutronix.de, hpa@linux.intel.com In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/bios] x86, bios: Make the x86 early memory reservation a kernel option Message-ID: Git-Commit-ID: 9ea77bdb39b62c9bf9fd3cdd1c25a9420bccd380 X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Thu, 26 Aug 2010 00:12:46 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3635 Lines: 109 Commit-ID: 9ea77bdb39b62c9bf9fd3cdd1c25a9420bccd380 Gitweb: http://git.kernel.org/tip/9ea77bdb39b62c9bf9fd3cdd1c25a9420bccd380 Author: H. Peter Anvin AuthorDate: Wed, 25 Aug 2010 16:38:20 -0700 Committer: H. Peter Anvin CommitDate: Wed, 25 Aug 2010 17:10:49 -0700 x86, bios: Make the x86 early memory reservation a kernel option Add a kernel command-line option so the x86 early memory reservation size can be adjusted at runtime instead of only at compile time. Suggested-by: Andrew Morton LKML-Reference: Signed-off-by: H. Peter Anvin --- Documentation/kernel-parameters.txt | 5 +++++ arch/x86/Kconfig | 2 +- arch/x86/kernel/setup.c | 28 ++++++++++++++++++++++++++-- 3 files changed, 32 insertions(+), 3 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 2c85c06..41ce93e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2150,6 +2150,11 @@ and is between 256 and 4096 characters. It is defined in the file Reserves a hole at the top of the kernel virtual address space. + reservelow= [X86] + Format: nn[K] + Set the amount of memory to reserve for BIOS at + the bottom of the address space. + reset_devices [KNL] Force drivers to reset the underlying device during initialization. diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 683ae8f..d359000 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1326,7 +1326,7 @@ config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK Set whether the default state of memory_corruption_check is on or off. -config X86_LOW_RESERVE +config X86_RESERVE_LOW int "Amount of low memory, in kilobytes, to reserve for the BIOS" default 64 range 4 640 diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index eb87f1c..af277e3 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -618,6 +618,8 @@ static __init void reserve_ibft_region(void) reserve_early_overlap_ok(addr, addr + size, "ibft"); } +static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10; + static void __init trim_bios_range(void) { /* @@ -627,9 +629,9 @@ static void __init trim_bios_range(void) * * This typically reserves additional memory (64KiB by default) * since some BIOSes are known to corrupt low memory. See the - * Kconfig help text for X86_LOW_RESERVE. + * Kconfig help text for X86_RESERVE_LOW. */ - e820_update_range(0, ALIGN(CONFIG_X86_LOW_RESERVE << 10, PAGE_SIZE), + e820_update_range(0, ALIGN(reserve_low, PAGE_SIZE), E820_RAM, E820_RESERVED); /* @@ -641,6 +643,28 @@ static void __init trim_bios_range(void) sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map); } +static int __init parse_reservelow(char *p) +{ + unsigned long long size; + + if (!p) + return -EINVAL; + + size = memparse(p, &p); + + if (size < 4096) + size = 4096; + + if (size > 640*1024) + size = 640*1024; + + reserve_low = size; + + return 0; +} + +early_param("reservelow", parse_reservelow); + /* * Determine if we were loaded by an EFI loader. If so, then we have also been * passed the efi memmap, systab, etc., so we should use these data structures -- 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/