OT: Evidence of A Intel Virtual Memory Vulnerability

[Brad Roberts]

On 1/3/2018 7:51 AM, Jack Stouffer via Digitalmars-d wrote:
> The gist of the story is that an Intel vulnerability is requiring OS 
> vendors to institute Page Table Isolation in their kernels. This fix has 
> an _across the board_ 5-7% slowdown on Intel chips.
> 
> Worse yet, programs which do lots of syscalls will see around a 30% 
> slowdown or more, including compilation.
> 
> AMD is not effected.
> 
> Details and discussion:
> Reddit: 
> https://www.reddit.com/r/sysadmin/comments/7nl8r0/intel_bug_incoming/
> HN: https://news.ycombinator.com/item?id=16046636

Calling it a vendor or architecture specific issue is a bit misleading, 
based on the reading I did today.  There's a couple different 
vulnerabilities here and they tie back to speculative (ie out of order) 
execution, timing of branch prediction, and timing of various 
conditions.  These techniques are _widely_ used among high speed 
processors and any that use them are likely to be vulnerable when an 
adversary can control and time execution of code and data in caches. 
The same basic techniques have shown up in a number of recent exploits, 
for example some of those in SSL and TLS over the last few years.

It's very interesting research and I fully expect more of this sort of 
issue as more and more research is done.