Re: UVM crash in NetBSD/i386 PAE with 32 GB of RAM

[Christoph Egger <christoph_egger%gmx.de@localhost>]

Am 21.01.14 20:54, schrieb David Laight:
> On Tue, Jan 21, 2014 at 10:31:08AM +0000, Emmanuel Dreyfus wrote:
>> On Mon, Jan 20, 2014 at 04:18:38PM +0000, Emmanuel Dreyfus wrote:
>>> Changing memory fixed the problem. The machine now boots 6.0 i386 PAE
>>> with SMP enabled and 128 GB of RAM installed, and it seems to be stable.
>>
>> But I spoke too fast. It is stable, but the i386 PAE kernel does not
>> sees more than 2 GB of memory. An amd64 kernel sees the whole 128 GB.
>>
>> Is it possible that the chipset cannot run PAE?
> 
> I doubt it.
> 
> 2G sounds like the amount of memory below 4G - but I'd have thought that
> would be 3G (or even 3.5G).

That depends on the PCI MMIO memory layout.

And I am wondering if 64bit PCI devices are accessable at all when their
PCI bar is above 4G.

Christoph