Re: perf: perf_fuzzer quickly locks up on 4.15-rc7

[Vince Weaver]

On Mon, 8 Jan 2018, Ingo Molnar wrote:
> 
> Note that the page table isolation (PTI) feature has a number of effects on perf 
> and on NMI handlers, so one of the things to try would be to disable PTI.

Yes, it seems to be a KPTI issue.

With KPTI disabled I can fuzz for a few hours, no problems.

With KPTI enabled the perf_fuzzer on this haswell machine will lock up 
within minutes.

It's a hard lockup with nothing over the serial console.  It is not 
deterministic/reproducible either.

Vince