From: Andi Kleen <ak@muc.de>
To: virtualization@lists.osdl.org
Subject: Re: [PATCH 5/7] Use %gs for per-cpu sections in kernel
Date: Sat, 23 Sep 2006 01:52:43 +0200
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On Saturday 23 September 2006 00:43, Jeremy Fitzhardinge wrote:
> Andi Kleen wrote:
> > BTW I changed my copy sorry. I redid the early PDA support
> > to not be in assembler.
> 
> I went to the trouble of making the PDA completely set up before any C 
> code ran.  

Yes, but your patch never applied to anything even remotely 
looking like the code in my tree. I got so frustrated that
I ended up reimplementing it in a cleaner way.

Now head.S calls i386_start_kernel() and that calls pda_init()
without any additional assembly code or other special cases etc. 

This is very similar to how x86-64 works.

> which means that that they 
> have to work from the first function prologue.

I mainly did it to fix lockdep.

I used to do mcount hacks myself, but you typically need
a few special annotations for those anyways so I am not too 
concerned about them.

> It also simplifies things to get all that set up ASAP so there's no 
> bootstrap dependency problem.

Yes no argument on that.

-Andi
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