LAPCI disabled for second Processor in 2.6.8-11-amd64-k8-smp kernel - need help reading source code
Siju George <[email protected]> Wed, 28 Dec 2005 20:41:19 +0530
| Newsgroups | org.kernel.vger.linux-smp |
|---|---|
| Message-ID | <[email protected]> |
Hi,
I need some help to sort out this :-)
The following lines appear in the dmesg of my Dual Opteron Server
running on 2.6.8-11-amd64-k8-smp kernel
--------------
Processor #0 15:5 APIC version 16
ACPI: LAPIC (acpi_id[0x02] lapic_id[0x01] enabled)
Processor #1 15:5 APIC version 16
ACPI: LAPIC (acpi_id[0x03] lapic_id[0x82] disabled)
ACPI: LAPIC (acpi_id[0x04] lapic_id[0x83] disabled)
---------------------------------
What is LAPIC?
Why is it disabled for the second processor?
Is it normal beavior?
I have posted to several mailinglist and got no reply on this :-(
I have traced to the kernel code at
http://fxr.watson.org/fxr/source/drivers/acpi/tables.c?v=linux-2.6.11.8#L121
From lines 121-127 I find this.
-----------------------------
case ACPI_MADT_LAPIC:
{
struct acpi_table_lapic *p =
(struct acpi_table_lapic*) header;
printk(KERN_INFO PREFIX "LAPIC (acpi_id[0x%02x]
lapic_id[0x%02x] %s)\n",
p->acpi_id, p->id,
p->flags.enabled?"enabled":"disabled");
}
----------------------------------
Could some one who works on the kernel or who knows C please interpret
this for me?
The code version is differrent but I hope it does not affect.
Please let me know if you need the full dmesg
Thankyou so much :-)
Kind Regards
Siju