From 1b5576e69a5fe168c08a159685ac366316ac9bbc Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Fri, 22 Jan 2010 11:21:04 +0800 Subject: x86: Remove BIOS data range from e820 In preparation for moving to the generic page_is_ram(), make explicit what we expect to be reserved and not reserved. Tested-by: Wu Fengguang Signed-off-by: Yinghai Lu LKML-Reference: <20100122033004.335813103@intel.com> Cc: Andrew Morton Signed-off-by: H. Peter Anvin --- arch/x86/kernel/setup.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) (limited to 'arch/x86/kernel/setup.c') diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index cdb6a8a506dd..f9b1f4e5ab74 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -650,6 +650,23 @@ static struct dmi_system_id __initdata bad_bios_dmi_table[] = { {} }; +static void __init trim_bios_range(void) +{ + /* + * A special case is the first 4Kb of memory; + * This is a BIOS owned area, not kernel ram, but generally + * not listed as such in the E820 table. + */ + e820_update_range(0, PAGE_SIZE, E820_RAM, E820_RESERVED); + /* + * special case: Some BIOSen report the PC BIOS + * area (640->1Mb) as ram even though it is not. + * take them out. + */ + e820_remove_range(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_RAM, 1); + sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map); +} + /* * 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 @@ -813,7 +830,7 @@ void __init setup_arch(char **cmdline_p) insert_resource(&iomem_resource, &data_resource); insert_resource(&iomem_resource, &bss_resource); - + trim_bios_range(); #ifdef CONFIG_X86_32 if (ppro_with_ram_bug()) { e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM, -- cgit v1.2.3 From e808bae2407a087bfd40200a27587898e5a9909d Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo Date: Tue, 9 Feb 2010 21:38:45 -0200 Subject: x86: Do not reserve brk for DMI if it's not going to be used This will save 64K bytes from memory when loading linux if DMI is disabled, which is good for embedded systems. Signed-off-by: Thadeu Lima de Souza Cascardo LKML-Reference: <1265758732-19320-1-git-send-email-cascardo@holoscopio.com> Signed-off-by: H. Peter Anvin --- arch/x86/kernel/setup.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86/kernel/setup.c') diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 3499b4fabc94..cb42109a55b4 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -121,7 +121,9 @@ unsigned long max_low_pfn_mapped; unsigned long max_pfn_mapped; +#ifdef CONFIG_DMI RESERVE_BRK(dmi_alloc, 65536); +#endif unsigned int boot_cpu_id __read_mostly; -- cgit v1.2.3