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| author | Yinghai Lu <Yinghai.Lu@Sun.COM> | 2008-02-22 13:37:26 -0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-04-17 17:40:49 +0200 |
| commit | 1e934dda0c77c8ad13fdda02074f2cfcea118a56 (patch) | |
| tree | 83c149b09859f143eb81e2447bcdd78e54e311f1 /Documentation/tty.txt | |
| parent | 3def3d6ddf43dbe20c00c3cbc38dfacc8586998f (diff) | |
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 <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'Documentation/tty.txt')
0 files changed, 0 insertions, 0 deletions