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From: mitchalsup@aol.com (MitchAlsup1)
Newsgroups: comp.arch
Subject: Re: Virtualization layers
Date: Wed, 16 Apr 2025 22:12:22 +0000
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On Wed, 16 Apr 2025 21:48:49 +0000, Stefan Monnier wrote:

>> Given 4 layers in the stack {Secure, Hyper, Super, User} and we have
>> interrupts targeting {Secure, Hyper, Super}, do we pick up any liability
>> or do we gain flexibility by being able to target interrupts directly to
>> {user} ?? (the 4th element).
>
> All these discussions seem to presume a very fixed structure that (I
> presume) corresponds to a typical situation in servers nowadays.
>
> But shouldn't the hardware aim for something more flexible to account
> for other use cases?

The goal is that::
The two layers in the middle can be managed as an accordion; supporting
any number of HVs and GuestOSs between Secure and User.

> E.g. What if I want to run my own VM as a user?  Or my own HV?
> That's likely to be a common desire for people working on the
> development and testing of OSes and HVs?

Use the accordion

>
>         Stefan