On Thu, Jun 15, 2017 at 11:14:27AM +0200, Maxime Villard wrote:
I can't see how this improves the security.
AFAIK on linux PMCs can be used without root.
We don't do application tracking, contrary to linux. That is, we don't
save/restore the counters on context switch. So the average user will have
only little interest in PMCs.
Verily the current implementation is mainly useful to measure the kernel
itself; when you make a change, and want to see whether the hit/miss ratios
are improved.
So yes, our implementation is not very useful. Also, we support only few
CPUs. But as I said it's still better than nothing, and so far I appear to
have been the only one that has shown (some) interest in developing this.
OK, so once we have proper userland support we can revisit the access rights