cpu does not support long mode

Nate Eldredge neldredge at math.ucsd.edu
Wed Jun 17 18:58:57 UTC 2009

On Wed, 17 Jun 2009, Jo Rhett wrote:

>> On Wed, 17 Jun 2009, Jo Rhett wrote:
>>> I've got a Tyan S2720 with dual Xeon 2.4G dual-core processors here that I 
>>> was going to test out 64-bit support with.  However, the system fails 
>>> during boot of the 7.2-RELEASE CD with
>>> warning: module 'acpi' already loaded
>>> Booting [/boot/kernel/kernel]...
>>> CPU does not support long mode
>>> OK
> On Jun 17, 2009, at 10:11 AM, Nate Eldredge wrote:
>> Do you have FreeBSD/i386 working on the machine?  If so, please install the 
>> misc/cpuid port and post the output of `cpuid'.
> Here it is:
> eax in    eax      ebx      ecx      edx
> 00000000 00000002 756e6547 6c65746e 49656e69
> 00000001 00000f27 0002080b 00000000 bfebfbff
> 00000002 665b5001 00000000 00000000 007b7040
> 80000000 80000004 00000000 00000000 00000000
> 80000001 00000000 00000000 00000000 00000000
> 80000002 20202020 20202020 20202020 20202020
> 80000003 6e492020 286c6574 58202952 286e6f65
> 80000004 20294d54 20555043 30342e32 007a4847
> Vendor ID: "GenuineIntel"; CPUID level 2
> Intel-specific functions:
> Version 00000f27:

Poking around on Intel's Processor Identification site, I found an entry 
with a matching version number of 0f27h.


There isn't a lot of info there, but it has the OEM order number 
RN80532KC056512.  Wikipedia lists that as one of the "Prestonia" family.


See the "Xeon 2.4" entry.

The main Wikipedia Xeon page describes Prestonia as a series of 130nm 
32-bit CPUs released in 2002.  (The first amd64 CPU to be released was 
AMD's Opteron in April 2003; Intel did not get in that game until the 
Nocona family was released in mid-2004.)


The Prestonia family was single-core, but supported hyper-threading, and 
so would appear to FreeBSD as two logical CPUs.  This is probably the 
source of most of the confusion.

> Hyper threading siblings: 2
> HT     Hyper Threading

Ah, there it is.

So it appears that you really do have a 32-bit machine on your hands. 
Sorry :(

This was some interesting research, by the way: I learned something about 
CPU history, and the horrific mess that is Intel's part numbering system.


Nate Eldredge
neldredge at math.ucsd.edu

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