[Info-vax] CRTL and RMS vs SSIO

[Arne Vajhøj]

On 10/12/2021 5:39 PM, Lawrence D’Oliveiro wrote:
> On Wednesday, October 13, 2021 at 9:54:14 AM UTC+13, Stephen Hoffman wrote:
>> 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?

Some.

Even though it may sound like totally irrelevant, then
there are implications.

The model with DCL in P1 space and loading and unloading
EXE in P0 space sort of rely on being able to blow the U stack
while keeping DCL in the S stack. And many programs depend
on process context.

> 
>> Other considerations awaiting VSI developers: any hypothetical chunks
>> of OpenVMS linked against Linux, seL4, or some of the other kernels
>> necessarily involves working within GPL2, which means VSI must write
>> all of that source code themselves, and must then release it.
> 
> Oracle vs Google notwithstanding, it has long been the position in most of the open-source community that APIs are not copyrightable.

Yes. But I am not sure that it is so relevant.

It is not a problem to keep user mode stuff under proprietary
license with a GPL kernel.

But keeping other kernel stuff under proprietary
license with an otherwise GPL kernel is potentially tricky.

The argument to use is well known:
     proprietary kernel code---(non kernel specific API)---GPL kernel code

It has been used in the past.

But not all GPL people consider it a valid model.

Arne