# [SOLVED] Kernel does not recognize Intel Xeon 3040 Dual Core

## Soef

Hi folks,

I have this problem and I cannot find a solution anywhere! Either this is has a really easy solution or I have some kind of configuration conflicts.

I have a server with a single Intel Xeon 3040 (Dual Core). However, my Gentoo (kernel 2.6.20-r8) only finds one processor. I've compiled kernels before on Inten Xeon's, and I expect to have 2 processors showing in /proc/cpuinfo.

Here is my 'cat /proc/cpuinfo' output:

```

processor       : 0

vendor_id       : GenuineIntel

cpu family      : 6

model           : 15

model name      : Intel(R) Xeon(R) CPU            3040  @ 1.86GHz

stepping        : 6

cpu MHz         : 1866.857

cache size      : 2048 KB

physical id     : 0

siblings        : 1

core id         : 0

cpu cores       : 1

fdiv_bug        : no

hlt_bug         : no

f00f_bug        : no

coma_bug        : no

fpu             : yes

fpu_exception   : yes

cpuid level     : 10

wp              : yes

flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc up pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr lahf_lm

bogomips        : 3739.97

clflush size    : 64

```

As you can see, its a Xeon support 'ht' and such. CPU family is '6', so i think 'newer xeon' option in Kernel (old xeon doesn't work either). What also is weird (or maybe not becouse my kernel doesn't find more) 'cpu cores' says only '1'...

Here is are my kernel options according to processor type:

```

[*] Symmetric multi-processing support

    Processor family (Core 2/newer Xeon)  --->

[ ] Generic x86 support

(4) Maximum number of CPUs (2-255)

[*] SMT (Hyperthreading) scheduler support

[*] Multi-core scheduler support

```

Here is my complete config: http://www.xs4all.nl/~fkoning9/.config

Anyone any idea what I am doing wrong? Please help me, this is breaking my head for over 24 hours now! Not sure I can take it much longer...

----------

## Genewb

 *Soef wrote:*   

> Hi folks,
> 
> Here is my 'cat /proc/cpuinfo' output:
> 
> ```
> ...

 

I could be wrong here, but I believe all Conroes and Allendales do not include HT, rebranded Xeon or not.

----------

## Soef

 *Genewb wrote:*   

> 
> 
> I could be wrong here, but I believe all Conroes and Allendales do not include HT, rebranded Xeon or not.

 

Still, 'ht' is in CPU flags...

What are you trying to say? Gentoo should not display more CPU's at all with this type?

----------

## eccerr0r

Do you have ACPI enabled (and compiled into the kernel), or APIC + MPS 1.1/1.4 , all enabled in BIOS?

What does the startup debug output say?

You should see two CPUs, at least my E6700 says two CPUs.  I was able to make one "disappear" by mucking with BIOS...

----------

## Genewb

 *Soef wrote:*   

>  *Genewb wrote:*   
> 
> I could be wrong here, but I believe all Conroes and Allendales do not include HT, rebranded Xeon or not. 
> 
> Still, 'ht' is in CPU flags...
> ...

 

I'm not trying to say anything other than what I said. What I'd do though, is to just try compiling your kernel without HT, since IIRC, people with Core 2s have had problems similar to your own with HT support in their kernel.

----------

## Soef

 *eccerr0r wrote:*   

> Do you have ACPI enabled (and compiled into the kernel), or APIC + MPS 1.1/1.4 , all enabled in BIOS?
> 
> What does the startup debug output say?
> 
> You should see two CPUs, at least my E6700 says two CPUs.  I was able to make one "disappear" by mucking with BIOS...

 

I do not have any ACPI compiled, it is turned on in BIOS though. Should I compile it in kernel??

----------

## Soef

Tried to compile ACPI in kernel, no luck though. BIOS doesn't say anythink about ACPI, its an Intel server. Maybe its on by default?

Any more idea's I could try?

----------

## Soef

My startup output (dmesg | grep CPU):

```

Initializing CPU#0

CPU: After generic identify, caps: bfebfbff 20100000 00000000 00000000 0000e3bd 00000000 00000001

CPU: After vendor identify, caps: bfebfbff 20100000 00000000 00000000 0000e3bd 00000000 00000001

CPU: L1 I cache: 32K, L1 D cache: 32K

CPU: L2 cache: 2048K

CPU: Physical Processor ID: 0

CPU: Processor Core ID: 0

CPU: After all inits, caps: bfebfbff 20100000 00000000 00000940 0000e3bd 00000000 00000001

Intel machine check reporting enabled on CPU#0.

CPU0: Intel(R) Xeon(R) CPU            3040  @ 1.86GHz stepping 06

Brought up 1 CPUs

```

----------

## Soef

 *Genewb wrote:*   

>  *Soef wrote:*    *Genewb wrote:*   
> 
> I could be wrong here, but I believe all Conroes and Allendales do not include HT, rebranded Xeon or not. 
> 
> Still, 'ht' is in CPU flags...
> ...

 

I looked it up, and the Xeon 3040 does not have HT support. It doesn't have Core 2 Duo either. It is just Core Duo.

I'm pretty sure I need to see 2 CPU's in cat /proc/cpuinfo... I searched google for cpuinfo output with the exact type CPU like mine and saw my proc having 2 cores and 2 procs in cpuinfo... So I am running on half speed now.

Maybe good to mention: in my grub.conf I have the following kernel line:

```
kernel /kernel-2.6.18-r6 root=/dev/md3 irqpoll
```

Maybe 'irqpoll' is the problem? I can't turn it off though, becouse it's needed for my LVM Raid setup.

----------

## Soef

I read somewhere via google. Something with the 2.6.18 - 2.6.20 kernels:

- Turn on ACPI in the kernel (Just ACPI, not processor sub modules or something).

- Expand your kernel-line in boot loader with 'acpi=ht'

Voila!! Thanks for the help!

----------

