I took a look at the situation. It boils down to this:
1. In the internal Xen tree, there is a bug (my fault) in which
firmware bootargs are overridden by the builtin "xen" bootarg. This
is fixed (by Hollis) in the current public Xen tree.
2. In the internal Xen tree, the SMP patch apparently causes
dom0 Linux to fail on Kawachiya's JS20, but no other JS20.
3. In the public Xen tree, the 32-bit objcopy produces an image that
Kawachiya's yaboot apparently cannot load.
The catch-22 is that if Maria updates the internal tree to get the fixes
in the public tree, the bootargs problem will go away, but the yaboot
problem will appear.
So we really need to know what yaboot is complaining about.
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