Re: System crash with perf_fuzzer (kernel: 5.0.0-rc3)

[Vince Weaver]

On Fri, 25 Jan 2019, Ravi Bangoria wrote:

> I'm seeing a system crash while running perf_fuzzer with upstream kernel
> on an Intel machine. I hit the crash twice (out of which I don't have log
> of first crash so don't know if the reason is same for both the crashes).
> I've attached my .config with the mail.
>                   type = PERF_TYPE_HARDWARE;



>   ========
> 
> And, I'm running fuzzer in a loop with *root*. (Let me know if running
> as root is harmful ;-) ).


There's a known issue related to Intel BTS events that you can trigger 
with the perf_fuzzer, even as a normal user.  I reported it a few months 
ago but I don't think it ever got resolved.  The traces you get look 
similar to some that you posted.

It's hard to track down as it doesn't seem to be a simple issue, but 
rather it looks like the BTS event handling is stomping over memory it 
shouldn't somehow.

Vince