From 1e934dda0c77c8ad13fdda02074f2cfcea118a56 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Fri, 22 Feb 2008 13:37:26 -0800 Subject: [PATCH] x86: insert_resorce for lapic addr after e820_reserve_resources when comparing the e820 direct from BIOS, and the one by kexec: BIOS-provided physical RAM map: - BIOS-e820: 0000000000000000 - 0000000000097400 (usable) + BIOS-e820: 0000000000000100 - 0000000000097400 (usable) BIOS-e820: 0000000000097400 - 00000000000a0000 (reserved) BIOS-e820: 00000000000e6000 - 0000000000100000 (reserved) BIOS-e820: 0000000000100000 - 00000000dffa0000 (usable) - BIOS-e820: 00000000dffae000 - 00000000dffb0000 type 9 + BIOS-e820: 00000000dffae000 - 00000000dffb0000 (reserved) BIOS-e820: 00000000dffb0000 - 00000000dffbe000 (ACPI data) BIOS-e820: 00000000dffbe000 - 00000000dfff0000 (ACPI NVS) BIOS-e820: 00000000dfff0000 - 00000000e0000000 (reserved) BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved) - BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved) =======> that is the local apic address... somewhere we lost it BIOS-e820: 00000000ff700000 - 0000000100000000 (reserved) BIOS-e820: 0000000100000000 - 0000004020000000 (usable) found one entry about reserved is missing for the kernel by kexec. it turns out init_apic_mappings is called before e820_reserve_resources in setup_arch. but e820_reserve_resources is using request_resource. it will not handle the conflicts. there are three ways to fix it: 1. change request_resource in e820_reserve_resources to to insert_resource 2. move init_apic_mappings after e820_reserve_resources 3. use late_initcall to insert lapic resource. this patch is using method 3, that is less intrusive. in later version could consider to use method 1. before patch fed20000-ffffffff : PCI Bus #00 fee00000-fee00fff : Local APIC fefff000-feffffff : pnp 00:09 ff700000-ffffffff : reserved with patch will get map in first kernel fed20000-ffffffff : PCI Bus #00 fee00000-fee00fff : Local APIC fee00000-fee00fff : reserved fefff000-feffffff : pnp 00:09 ff700000-ffffffff : reserved Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar --- arch/x86/kernel/apic_64.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c index 7d8ffdaa0ab3..ac2405ed504d 100644 --- a/arch/x86/kernel/apic_64.c +++ b/arch/x86/kernel/apic_64.c @@ -881,11 +881,6 @@ void __init init_apic_mappings(void) apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n", APIC_BASE, apic_phys); - /* Put local APIC into the resource map. */ - lapic_resource.start = apic_phys; - lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1; - insert_resource(&iomem_resource, &lapic_resource); - /* * Fetch the APIC ID of the BSP in case we have a * default configuration (or the MP table is broken). @@ -1300,3 +1295,21 @@ static __init int setup_apicpmtimer(char *s) } __setup("apicpmtimer", setup_apicpmtimer); +static int __init lapic_insert_resource(void) +{ + if (!apic_phys) + return -1; + + /* Put local APIC into the resource map. */ + lapic_resource.start = apic_phys; + lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1; + insert_resource(&iomem_resource, &lapic_resource); + + return 0; +} + +/* + * need call insert after e820_reserve_resources() + * that is using request_resource + */ +late_initcall(lapic_insert_resource);