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From: "Luke A. Guest" <laguest@archeia.com>
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Subject: Re: The Ravenscar profile and capabilities paradigm
Date: Tue, 12 Oct 2021 12:58:48 +0100
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On 12/10/2021 12:51, Richard Iswara wrote:

>>>> there isn't any existing OS that provides capability-security from the
>>>> ground up, I intend to implement my own.
>>>>
>>> seL4? The whitepaper includes the proofs also.
>> eh yes, I forgot seL4, however it isn't much used I think
> Has Qualcomm and Apple iOS abandoned it when it changed from OKL4 to seL4?
> I thought they use it for isolating their modem firmware from general OS.
> 

The biggest flaw in L4 I found is that sigma0 cannot claim memory back 
from processes when it runs out. There was apparently work being done, 
but I don't know if they did it.