Re: [Squeak-VMdev] Versiojn 4 changes

[Andreas R. <and...@gm...>]

[fixed bit objects]
> Like allocating video memory? Great! We need this - GPUs are becoming
> general-purpose co-processors now (see http://www.gpgpu.org/).

This would be one of the things you *might* use it for. All I'm really
saying is that we should have something that allows us to load/save these
"bit objects" without having to do ridiculous amounts of relocation.

> Are there security implications of this? It should be impossible from
> the image to just allocate some random memory, I suspect.

Unrelated to the V4 aspects. Those things need to be handled by plugins
anyway. Say if you want to use the ATI client texture storage (which I *do*
want to use) you need to have the lower-level hooks to get this right.

> Also, are there any hooks we should set into place to allow secure
> execution of ... whatever? Just thinking aloud. If we need any bits
> security-wise, now would be the time to get them in.

Not at the VM level, I don't think. These issues must be addressed at a
higher level and we really shouldn't start handing out ACLs or similar and
then try to guess if some portion of Squeak code can be "trusted" or not.
Security doesn't work well (if at all) on this level. The only reason why we
have the security hooks we have today is that when we needed to ship at DOL
there simply wasn't any viable solution other than building in these "last
resort hooks" that we did. Not that they are "secure" in any reasonable
meaning of the word. We're just lucky that no seasoned hacker sees Squeak a
viable target for doing some Real Harm (tm).

Cheers,
  - Andreas