[Info-vax] CRTL and RMS vs SSIO

[Dave Froble]

On 10/13/2021 2:14 PM, Simon Clubley wrote:
> On 2021-10-12, Lawrence D?Oliveiro <lawrencedo99 at gmail.com> wrote:
>> On Wednesday, October 13, 2021 at 9:54:14 AM UTC+13, Stephen Hoffman wrote:
>>> The DEC OpenVMS advanced development group did do a prototype of
>>> OpenVMS on Mach a ~quarter-century ago.
>>
>> Yeah, but Mach is a microkernel, with all the downsides that microkernels have.
>>
>
> Microkernels have moved on and microkernels have massive security advantages.
>
> BTW, QNX, which is a RTOS with a massive user base, is microkernel based.
>
>>> Possible areas where kernel modifications might necessary? Linux memory
>>> management is thoroughly two-ring, and OpenVMS expectations are
>>> four-ring. Do you drop those areas from OpenVMS, and force app source
>>> code changes?
>>
>> Where is there app code that cares about this?
>>
>
> Any program that interacts with DCL for one simple example.
>
> In the current VMS design, you can't move DCL into user mode, or allow
> user-controlled code to execute in DCL's supervisor mode, without ending
> up with an operating system that has all the security of MS-DOS.

MS-DOS has excellent security.

When nothing can be done, that is excellent security.


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