[Arm-netbook] microkernels

[Paul Boddie]

On Tuesday 11. December 2018 01.46.29 Luke Kenneth Casson Leighton wrote:
> 
>  SE/L4.  one research group actually created a complete
> minimum-compliant POSIX subsystem on top of SE/L4, absolutely nothing
> to do with any operating system "per se", and then successfully ported
> an entire qt-based webkit browser *and all its dependencies* to run on
> it.

Was this related to Genode or something else? I know that Genode 
supports/supported a WebKit browser - maybe Arora - and that it supports a 
range of microkernels, although the focus seems to be on using their favoured 
Nova microkernel instead these days [*].

> the "filesystem" was entirely flat.  no subdirectories.  so when i say
> "minimally compliant" it really really was "minimally compliant".

That would be an odd decision to make given that it would need to have a 
filesystem of some kind and that beyond a rudimentary memory-based temporary 
filesystem, pretty much all of the ones out there have directories. If they'd 
gone to the trouble of porting a WebKit browser, porting an established 
filesystem would surely have been straightforward.

L4Re has virtual filesystem support, but it seems pretty limited in a number 
of ways, and the bulk of the heavy lifting needed to support dynamic linking 
seems to be left to a "rom" filesystem. But even that supports directories. 
(Of course, L4Re is not aimed at seL4, but there are fairly comparable things 
for seL4, I believe.)

Paul

[*] As is increasingly customary with various projects, I hesitate to depict 
Genode in any particular way, even after digging through the copious 
promotional/educational materials so that I might precipitate a coherent 
impression, in case it gets perceived as misrepresenting something or someone.