Re: Dom0 crash with old style AMD NUMA detection

[Andre Przywara <andre.przywara@amd.com>]

On 09/14/2012 08:58 PM, Konrad Rzeszutek Wilk wrote:
>>>> [    0.000000] Kernel panic - not syncing: Attempted to kill the idle task!
>>>> (XEN) Domain 0 crashed: 'noreboot' set - not rebooting.
>>>>
>>>>
>>>>
>>>> The obvious solution would be to explicitly deny northbridge scanning
>>>> when running as Dom0, though I am not sure how to implement this without
>>>> upsetting the other kernel folks about "that crappy Xen thing" again ;-)
>>>
>>> Heh.
>>> Is there a numa=0 option that could be used to override it to turn it
>>> off?
>>
>> Not compile tested.. but was thinking something like this:
>
> ping?

That looks good to me - at least for the time being.
I just want to check how this interacts with upcoming Dom0 NUMA support. 
It wouldn't be too clever if we deliberately disable NUMA and future Xen 
version will allow us to use it. So let me check if I can confine this 
turn-off to the fallback K8 northbridge reading.

Thanks,
Andre.

>>
>> diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
>> index 43fd630..838cc1f 100644
>> --- a/arch/x86/xen/setup.c
>> +++ b/arch/x86/xen/setup.c
>> @@ -17,6 +17,7 @@
>>   #include <asm/e820.h>
>>   #include <asm/setup.h>
>>   #include <asm/acpi.h>
>> +#include <asm/numa.h>
>>   #include <asm/xen/hypervisor.h>
>>   #include <asm/xen/hypercall.h>
>>
>> @@ -528,4 +529,7 @@ void __init xen_arch_setup(void)
>>   	disable_cpufreq();
>>   	WARN_ON(set_pm_idle_to_default());
>>   	fiddle_vdso();
>> +#ifdef CONFIG_NUMA
>> +	numa_off = 1;
>> +#endif
>>   }
>



-- 
Andre Przywara
AMD-OSRC (Dresden)
Tel: x29712