[Info-vax] Intel junk...Kernel-memory-leaking Intel processor design flaw forces Linux, Windows redesign

[Pabst Blue Ribbon]

Alan Browne <bitbucket at blackhole.com> wrote:
> On 2018-01-05 09:15, DaveFroble wrote:
>> Jan-Erik Soderholm wrote:
> 
>>> Becuse the designers, for performance reasons, has mapped kernel memory
>>> into the user process address space and relies on the OS to check
>>> protection before any kernel memory (or code) is accessed.
>>> 
>>> The issue with the current issues is that the hardware (the CPU) does
>>> these accesses in hardware "under the hood" without control by the OS.
>>> 
>>> If you map your kernel memory in another way that uses the hardware
>>> protection facilities, you are (as I understand) safe, at the cost
>>> of worse performance to switch between user and kernel mode.
>>> 
>>> 
>> 
>> As I wrote, someone dropped the ball on this one.
>> 
>> Speculative execution is part of the HW, not software.  It appears the 
>> HW doesn't follow it's own rules.  Or, perhaps I don't actually 
>> understand the problem?
> 
> At least as well as I do.  These are very complex mechanisms and 
> complexity is usually where you're most likely to get problems.
> 
> In this case the h/w implementation didn't reflect the design goal.
> 
> This means intel had very poor design review and abysmal testing of 
> security features.

I doubt it. Yes, it's assumption but I think Intel was aware and gave OK to
flawed design because of performance/cost.