Thanks Christian for the info on initrd.
Technical musings - how does root=LABEL=xxx really work?
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The kernel starts booting, and loads an initrd (initial ram disk).
The kernel runs the 'linuxrc' script in the initrd.
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Use pivot_root to make it the current root.
Since CFE loads initrd in our case, not the kernel it seems a little different.
I was wondering how the kernel knows how to find how to call the
code in initrd (and whether the initrd was even loaded).
Our kernel hardcoded to know that initrd is at 0x2400000?
not that I'm anywhere near to building kernels here however.
tom