RE: [discuss] [OOPS] powernow on smp dual core amd64

Langsdorf, Mark
2005-06-13T22:47:32Z

> On Mon, 2005-06-13 at 16:47 -0500, Langsdorf, Mark wrote:
> > Okay, I think I have figured this out. During initialization, the
> > cpufreq infrastruture only initializes the first core of each
> > processor. When a request comes into the second core, it's data
> > structre is unitialized and we get the null point dereference.
> >
> > The solution is to assign the pointer to the data structure for the
> > first core to all the other cores.
> >
> > Tom, could you try this patch and see if it helps?
>
> Yes! It fixed the panic. I get much further.

Great, I'll test that some more then submit it.

> Unfortunately, after starting cpuspeed daemon, I get this:

It looks like it's happening sometime after cpuspeed starts.
Could you disable cpuspeed and see if the problem still
occurs?

> Starting cpuspeed: [ OK ]
> Starting pcmcia: Starting PCMCIA services:
> CPU 6: Machine Check Exception: 4 Bank 4:
> b200000000070f0f
> TSC 4129a3d70d

> Code: Bad RIP value.
> RIP [<00000000000000ff>] RSP <ffff81003fe63fa0>
> CR2: 00000000000000ff
> <0>Kernel panic - not syncing: Oops

Andi said that "Something tried to access a physical memory
address that was not mapped in the CPU." Andi, is this
related to the bug that you thought might have been fixed
in 2.6.12-rc6-git4?

-Mark Langsdorf
AMD, Inc.