CPU2 gone "missing" on 4 CPU box.

CPU2 gone "missing" on 4 CPU box.

[Chris Evans]

Hello-

I've got a very interesting problem with a 4 CPU box. I've
never seen anything quite like it.
After booting, all 4 CPUs seem to be available (e.g.
/proc/cpuinfo sees them all), but one of them is never
used for anything. It always stays at 100% idle. So it
is effectively a 3 CPU box :-(

There is a highly suspicious entry in the kernel logs
after bootup. It shows some differing values for the CPU
which does not come up properly. Here is the entry:

cpu: 0, clocks: 996796, slice: 199359
CPU0<T0:996784,T1:797424,D:1,S:199359,C:996796>
cpu: 1, clocks: 996796, slice: 199359
cpu: 2, clocks: 996796, slice: 199359
cpu: 3, clocks: 996796, slice: 199359
CPU2<T0:996784,T1:-133220960,D:133619667,S:199359,C:996796>
CPU1<T0:996784,T1:598064,D:2,S:199359,C:996796>
CPU3<T0:996784,T1:199344,D:4,S:199359,C:996796>

As you can see, CPU2 has some weird looking values for
"T1" and "D", compared with CPU0, CPU1 and CPU3.

Has anyone seen anything like this?

The kernel is:
Linux <snip> 2.4.9-e.12enterprise #1 SMP Tue Feb 11
01:29:18 EST 2003 i686 unknown

I'm not entirely sure what the hardware is because the
machine is remote.

Thanks in advance.
Chris

Re: CPU2 gone "missing" on 4 CPU box.

[Alan Cox]

On Thu, 2003-03-27 at 14:30, Chris Evans wrote:
> The kernel is:
> Linux <snip> 2.4.9-e.12enterprise #1 SMP Tue Feb 11
> 01:29:18 EST 2003 i686 unknown

Stick it in Red Hat bugzilla. The RHAS and United Linux
enterprise trees are so diverged from the "genuine article"
you really need to take it up with the vendor.

Alan