How should anaconda check for PAE? (was Re: arch fun.)

[Chris Lalancette]

Thorsten Leemhuis wrote:
> On 25.02.2009 13:27, Chris Lalancette wrote:
>> Gerd Hoffmann wrote:
>>> We can also simply do this:
>>>
>>>  - Install PAE kernel if the CPU supports PAE.
>>>
>>> i.e. make PAE the default kernel.
>> Yes, I really think we should just do this.  It's simple, it means we get the
>> logic right for Xen as well as bare-metal (without any special cases), and the
>> performance hit for those who have PAE and < 4GB isn't that bad, I don't think
>> (although numbers one way or the other would be interesting to see).
> 
> What about compatibility problems? My old laptop had a PAE capable CPU 
> but could not boot a PAE kernel -- I noticed when I was trying a PAE 
> kernel for some tests two or three years ago. I asked a kernel-developer 
> back then if it was worth reporting and I got told that such problems 
> are not unusual and often BIOS or hardware problems. Those likely didn't 
> vanish magically is that statement is correct.

Hm, it's an interesting point, and not one that I've heard about or seen before.
 Xen in Fedora required PAE for quite some time, and despite plenty of other
problems (mostly having to do with people wanting to run Xen on non-PAE
platforms), we didn't hear about any of this specific problem.  Doesn't mean it
doesn't exist, though :).

Do you have pointers to specific problems?  A quick google didn't turn up
anything, but I didn't try all that hard.

-- 
Chris Lalancette