[Info-vax] Intel junk...Kernel-memory-leaking Intel processor design flaw forces Linux, Windows redesign

[Johnny Billquist]

On 2018-01-06 12:40, johnwallace4 at yahoo.co.uk wrote:
> Alpha did/does have a documented architecture, and
> implementations have documented behaviours (as did,
> fwiw, various PDP11s and similar - this isn't rocket
> science).

This is slightly offtopic, but anyway...
Actually, the PDP-11 did not have a documented architecture, and that 
was recognized over time as one of the big problems of the PDP-11, and 
why DEC did such a thorough job on the VAX with the architecture 
reference manual.

For the PDP-11, different models do behave differently on some more odd 
things, and there is no defined "right" way.

(That said, had the PDP-11 ever had speculative execution and all those 
fanciness, it would still be pretty safe, since the PDP-11 actually have 
different page tables for different processor modes, and also have 
execute only page protection and cannot execute code on the stack or 
other data areas, if properly set up. :-) )

   Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol