[Info-vax] VSI: "Official 8.4-1H1 Launch"

[Bill Gunshannon]

In article <mkth2s$8mp$1 at dont-email.me>,
	David Froble <davef at tsoft-inc.com> writes:
> JF Mezei wrote:
>> I apologize for having questions in advance. Having deffective genes is
>> not my fault :-)
> 
> Yes it is   :-)
> 
> 
>> At what point in the boot sequence does VMS establish virtual memory,
>> and the various modes for code execution (and memory protection) ?
>> 
>> Would it be correct that this section of the boot is where the most work
>> is needed to tailor to an architecture such as x86 ?
>> 
>> When VMS implements the various memory protection schemes, is this a one
>> time x86 specific setup early in boot, or do those x86 specific changes
>> propagate well beyond initial boot all the way (for instance) to image
>> activator etc ?
> 
> I haven't been near this stuff for many, many years.  I can only answer 
> from long ago experience.  Most from RSTS, and I've probably forgotten 
> 90% of that.
> 
> The first thing that happens is a rather simple task of copying 
> essential code into memory.  At this time there is no virtual memory, 
> because the code to support it is not present.
> 
> What is essential code?  That can vary.  I don't know exactly how VMS 
> works at this stage.  What I will guess is that you don't have VM until 
> the code that handles VM is loaded and running.
> 
> As for the autoconfig, I'm guessing the code at that point probes for 
> various HW.  That's part of the reason for HW releases, along with 
> drivers.  Can't probe for something you don't know exists.  If a device 
> is found, then requirements for that device are loaded, and whatever 
> device tables are updated.
> 
> But enough guessing.  The short answer, get and study the Internals and 
> Data Structures book.

This may come off as a really stupid question, but isn't VMS a monolithic
kernel?  In which case VM and everything else is available as soon as the
secondary (or tertiary) boot loader loads the kernel into memory and jumps
there.  Right?

bill

-- 
Bill Gunshannon          |  de-moc-ra-cy (di mok' ra see) n.  Three wolves
billg999 at cs.scranton.edu |  and a sheep voting on what's for dinner.
University of Scranton   |
Scranton, Pennsylvania   |         #include <std.disclaimer.h>