debxo 0.3 release

John Gilmore gnu at toad.com
Sun Nov 2 23:46:09 EST 2008


> things that I can see as possibly needed:
> hardware encryption engine (does this show up to the kernel as an 
> available encryption device? (it would be handy if at least the 
> development builds of the kernel enabled /proc/config.gz for all xo 
> distros (including the OLPC builds) it costs about 10k 
> compressed, 40k raw)

The Geode hardware encryption engine is useless for Unix user
programs.  It was apparently designed for/by hardware engineers who
had no idea how an operating system or a crypto library works.  It can
only be accessed via DMA using physical addresses, which means a user
program that wanted to do AES would have to do a kernel call and the
kernel would have to copy the data to reside in contiguous physical
memory, then copy the results back and return to user space.  It's
much faster to simply do AES in software for virtually every
application (and that software's already coded and tested).  If the
Geode designers had only made the engine accessible via unprivileged
instructions that took operands from registers or virtual memory, we'd
have seen a very different result.

> is there anything else that may need special handling?

Suspend/resume, e.g. when you close the lid.

	John



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