Re: [PATCH v2] x86: Disable kernel stack offset randomization for !TSC

[Maciej W. Rozycki]

Hi Jason,

> >  Thank you for your input.  I've had a look at the function and it seems a
> > bit heavyweight compared to a mere single CPU instruction, but I guess why
> > not.  Do you have any performance figures (in terms of CPU cycles) for the
> > usual cases?  Offhand I'm not sure how I could benchmark it myself.
> 
> Generally it's very very fast, as most cases wind up being only a
> memcpy -- in this case, a single byte copy. So by and large it should
> be suitable. It's fast enough now that most networking things are able
> to use it. And lots of other places where you'd want really high
> performance. So I'd expect it's okay to use here too. And if it is too
> slow, we should figure out how to make it faster. But I don't suspect
> it'll be too slow.

 Thank you for your explanation.  I have v3 ready for submission; would 
you mind if I added you with a Suggested-by: tag?

  Maciej