kernel panic during kernel module load (powerpc specific part)

[Gabriel Paubert]

On Tue, Jun 05, 2012 at 08:00:42AM +1000, Benjamin Herrenschmidt wrote:
> On Mon, 2012-06-04 at 13:03 +0200, Gabriel Paubert wrote:
> > There is no conflict to the ABI. These functions are supposed to be
> > directly reachable from whatever code
> > section may need them.
> > 
> > Now I have a question: how did you get the need for this?
> > 
> > None of my kernels uses them:
> > - if I compile with -O2, the compiler simply expands epilogue and
> > prologue to series of lwz and stw
> > - if I compile with -Os, the compiler generates lmw/stmw which give
> > the smallest possible cache footprint
> > 
> > Neither did I find a single reference to these functions in several
> > systems that I grepped for.
> 
> Newer gcc's ... even worse, with -Os, it does it for a single register
> spill afaik. At least that's how I hit it with grub2 using whatever gcc
> is in fc17.

Ok, it's beyond stupid, and at this point must be considered a gcc bug.

	Gabriel