Re: [PATCH] Make Intel 8-way Xeons boot again

[Yinghai Lu <yinghai@kernel.org>]

On Sat, Jan 9, 2010 at 6:30 PM, Ananth N Mavinakayanahalli
<ananth@in.ibm.com> wrote:
> On Sat, Jan 09, 2010 at 01:13:39PM -0800, Yinghai Lu wrote:
>> On Sat, Jan 9, 2010 at 2:10 AM, Ananth N Mavinakayanahalli
>> <ananth@in.ibm.com> wrote:
>> > On an 8-way system with Intel Xeon X7350 CPUs, booting 2.6.32 or newer
>> > kernels fails at:
>> >
>> > ...
>> > CPU0: Intel(R) Xeon(R) CPU           X7350  @ 2.93GHz stepping 0b
>> > Booting Node   0, Processors  #1 #2 #3 #4 #5 #6 #7 Ok.
>> > Brought up 8 CPUs
>> > Total of 8 processors activated (46906.05 BogoMIPS).
>> >
>> > Git bisect showed 2fbd07a5f as the offending commit.
>> >
>> > With the patch below, I am able to boot the latest Linus' git tree on
>> > the machine. If this patch is correct, it needs to get into the stable
>> > tree too.
>> >
>> > Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
>> > ---
>> > Index: linux-2.6/arch/x86/kernel/apic/probe_64.c
>> > ===================================================================
>> > --- linux-2.6.orig/arch/x86/kernel/apic/probe_64.c      2010-01-09 14:54:29.000000000 +0530
>> > +++ linux-2.6/arch/x86/kernel/apic/probe_64.c   2010-01-09 14:57:53.000000000 +0530
>> > @@ -70,7 +70,7 @@
>> >        if (apic == &apic_flat) {
>> >                switch (boot_cpu_data.x86_vendor) {
>> >                case X86_VENDOR_INTEL:
>> > -                       if (num_processors > 8)
>> > +                       if (num_processors >= 8)
>> >                                apic = &apic_physflat;
>> >                        break;
>> >                case X86_VENDOR_AMD:
>>
>> can you send out whole bootlog with apic=debug?
>
> Here it is:
> ACPI: LAPIC (acpi_id[0x00] lapic_id[0x0c] enabled)
> ACPI: LAPIC (acpi_id[0x01] lapic_id[0x10] enabled)
> ACPI: LAPIC (acpi_id[0x02] lapic_id[0x0d] enabled)
> ACPI: LAPIC (acpi_id[0x03] lapic_id[0x11] enabled)
> ACPI: LAPIC (acpi_id[0x04] lapic_id[0x0e] enabled)
> ACPI: LAPIC (acpi_id[0x05] lapic_id[0x12] enabled)
> ACPI: LAPIC (acpi_id[0x06] lapic_id[0x0f] enabled)
> ACPI: LAPIC (acpi_id[0x07] lapic_id[0x13] enabled)
...
> Setting APIC routing to flat
> Getting VERSION: 50014
> Getting VERSION: 50014
> Getting ID: c000000
> Getting ID: f3000000
> Getting LVT0: 700
> Getting LVT1: 400
> enabled ExtINT on CPU#0
> ESR value before enabling vector: 0x00000040  after: 0x00000000
> ENABLING IO-APIC IRQs
> ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1
> CPU0: Intel(R) Xeon(R) CPU           X7350  @ 2.93GHz stepping 0b
...

the BSP's physical apic id is 0x0c instead of 0.

not sure Suresh test that or not.

YH