[Info-vax] VMS port to x86

[Bob Koehler]

In article <c0ce4a20-dd64-4c50-92b2-c0cf480ce336 at q11g2000vbu.googlegroups.com>, John Wallace <johnwallace4 at yahoo.co.uk> writes:
> 
> There's a discussion for anyone interested to have about how well the
> AMD64 and IA64 protection mechanisms map onto the VMS-required
> mechanisms, and how exploit-proof they might be in reality. My
> recollection is that Alpha only had two protection levels in the
> hardware, the rest was implemented in PALcode, but the Alpha
> architecture and design and the VMS implementation appeared reasonably
> leakproof, subject to the occasional near-inevitable software bug.

   Yes, there are some "OS defined" bits in Alpha where you might
   expect support for twice as many modes.

   Alpha modes aren't a perfect map to VAX, and neither are IA64,
   but they are good enough and IA32 looks like it would be, too.