[Info-vax] Intel x86-64 Processor Design Security Vulnerability?

[Simon Clubley]

On 2018-01-02, Stephen Hoffman <seaohveh at hoffmanlabs.invalid> wrote:
> On 2018-01-02 18:24:24 +0000, Simon Clubley said:
>> 
>> If this is what it sounds like, I wonder if a microkernel based 
>> operating system would be more protected against this than a monolithic 
>> operating system would be ?
>
> For those inclined, I'd expect that OpenVMS can be targeted by 
> rowhammer on both Itanium and Alpha.  Rowhammer is likely too "new" to 
> particularly have hardware mitigations available in either platform, 
> too.
>
> VSI hasn't specifically indicated if they're porting OpenVMS directly 
> or if they're going to repeat the earlier experimental Mach port.  But 
> I'd expect that they're porting without using Mach, given there were no 
> discussions of Mach at the boot camp.
>

No, I wasn't expecting VSI to start using a microkernel (although I was
indeed aware of the older VMS on Mach experiment).

I was thinking more that the microkernel internals could be more
shielded than in a monolithic kernel, although until we know the
details, that's just a guess.

What is interesting is that people put down microkernels because of
the additional overheads they incur, but now monolithic kernels are
likely to have most, if not all, of those overheads on Intel 64-bit
processors without getting the benefits that come with microkernels.

In fact, some microkernel designs mitigate a part of this overhead,
so I wonder if the monolithic kernels are actually going to become 
slightly _slower_ than a microkernel for some things ?

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
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