Problems with AMD64 and 8 GB RAM?

[Scott Long]

Jon Noack wrote:
> On 03/30/05 23:14, Greg 'groggy' Lehey wrote:
> 
>> On Wednesday, 30 March 2005 at 21:28:36 -0700, Scott Long wrote:
>>
>>> Greg 'groggy' Lehey wrote:
>>>
>>>> On Wednesday, 30 March 2005 at 23:01:03 -0500, John Baldwin wrote:
>>>>
>>>>> On Mar 30, 2005, at 8:54 PM, Greg 'groggy' Lehey wrote:
>>>>>
>>>>>>> lapic0: LINT1 trigger: edge
>>>>>>> lapic0: LINT1 polarity: high
>>>>>>> lapic1: Routing NMI -> LINT1
>>>>>>> lapic1: LINT1 trigger: edge
>>>>>>> lapic1: LINT1 polarity: high
>>>>>>> -ioapic0 <Version 0.3> irqs 0-23 on motherboard
>>>>>>> +ioapic0 <Version 0.0> irqs 0-23 on motherboard
>>>>>>> cpu0 BSP:
>>>>>>>   ID: 0x00000000   VER: 0x00040010 LDR: 0x01000000 DFR: 0x0fffffff
>>>>>>> lint0: 0x00010700 lint1: 0x00000400 TPR: 0x00000000 SVR: 0x000001ff
>>>>>
>>>>>
>>>>> This shows that in the - case the APIC is broken somehow (0.0 isn't a
>>>>> valid I/O APIC version).
>>>>
>>>>
>>>> You mean the + case, I suppose.  Yes, that's what I suspected.
>>>>
>>>>
>>>>> It would seem that the system has mapped RAM over top of the I/O
>>>>> APIC perhaps?
>>>>
>>>>
>>>> That's what I suspected too, but imp doesn't think so.
>>>
>>>
>>> I'd be more inclined to believe that there is an erroneous mapping
>>> by the OS, not that things are fundamentally broken in hardware.
>>
>>
>> Agreed.  This has been my favourite hypothesis all along.  But isn't
>> that what jhb is saying?
>>
>>> Your SMAP table shows everything correctly.  It's becoming hard to
>>> break through your pre-concieved notions here and explain how things
>>> actually work.
>>
>>
>> No, there's nothing to break through.  I think you're just having
>> problems
>>
>> 1.  expressing yourself, and
>> 2.  understanding what I'm saying.
>>
>> I have no preconceived notions.  All I can see here is an antagonistic
>> attitude on your part.  What's the problem?  You'll recall from my
>> first message that I asked for suggestions about how to approach the
>> issue.  jhb provided some; you haven't so far.  From what you've
>> written, it's unclear whether you disagree with jhb or not.  If you
>> do, why?  If you don't, what's your point here?
>>
>>>>> It would be interesting to see the contents of your MADT to see if
>>>>> it's trying to use a 64-bit PA for your APIC.
>>>>
>>>>
>>>> Any suggestions about how to do so?
>>>
>>>
>>> man acpidump
>>
>>
>> How do you run that on a system that won't boot?
> 
> 
> You said the system worked with 4 GB (albeit detecting only 3.5 GB).  My 
> perception of this whole ACPI thing is that it is fixed in your BIOS 
> (although it can be overridden by the OS).  As such, the amount of RAM 
> you have in the machine shouldn't change acpidump results.  Is that not 
> correct?
> 
> Jon

This is absolutely correct.

Scott