Re: [Mactel-linux-users] lost one cpu core when upgraded to RHEL 5.5

[Geoffrey <li...@se...>]

Geoffrey wrote:
> Anyone out there running 64 bit OS on a macbook pro 4,1.  I upgraded 
> from 32 bit Red Hat EL 5.4 to 64 bit RHEL 5.4, then again to 64 bit RHEL 
> 5.5, which is actually still in beta.  I don't know if I lost the core 
> in the 64 bit 5.4 or not.  I see the following from dmesg:
> 
> SMP: Allowing 2 CPUs, 0 hotplug CPUs
> .
> .
> SMP alternatives: switching to UP code
> .
> .
> SMP motherboard not detected.
> .
> .
> SMP disabled

Thought I'd update the list with a recent success:

For whatever reason, I could not get the initial installation RHEL 5.4 
disk to even boot until I stumbled across a link that suggested the 
following boot parms:

acpi=force noapic irqpoll

I don't know why they worked, but they did.  Once installed, I found 
that I had to add them to my grub.conf to get the install to boot, but 
all was happy.  After moving to 64bit, I lost one core of my two core 
processor.  After much discussion with RH, I revisited these parameters 
and found that by removing the noapic, parm, my macbook would still boot 
and I got both cores.  The weird thing is, I've tried every combination 
of these parms before in order to remove them from my boot process in 
the past, but my macbook would not boot.  There must be something about 
the latest RHEL 5.5 kernel that resolved that issue.

The weird thing is, I did not have this issue on 32bit RHEL 5.4.  That 
is, I had both cores using all these parms.

-- 
Until later, Geoffrey

"I predict future happiness for America if they can prevent
the government from wasting the labors of the people under
the pretense of taking care of them."
- Thomas Jefferson