Userapi, Reflection

[Emiel Kollof]

* Lewis, Todd (todd.lewis at xxxxxx) wrote:
> Maybe I'm misunderstanding, I don't understand why code needs to be in the
> kernel.  Why not just, at run-time, link in the appropriate
> syscall-decoder/rewriter depending on the personality of the binary?  New
> syscalls for linux would just require updating
> /lib/libpersonality_linux.so...

I like this idea. The more we can push into userspace, the better.

> Also, Matt, when you're talking about 0x80 being a userspace interrupt,
> would that require rewriting the binary, valgrind-style, or is there some
> hardware trick that could be used, or is there some other way?  My
> understanding of x86 is that 0x80 always context-switches into the kernel,
> but I am a novice in such matters.

I don't think that apps need to be rewritten. int 0x80 can always be
hooked up to do something else (like figure out which syscall is called
from which personality, and then send the required dragonfly message).

Of course, IANAAH (asm hacker), so I could be completely wrong about
this.

Cheers,
Emiel
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