Re: Current mainline git (24e700e291d52bd2) hangs when building e.g. perf

[Thomas Gleixner]

On Fri, 8 Sep 2017, Markus Trippelsdorf wrote:

CC+ Borislav. He might have access to such a beast

> On 2017.09.07 at 08:28 +0200, Markus Trippelsdorf wrote:
> > On 2017.09.06 at 15:15 +0200, Markus Trippelsdorf wrote:
> > > On 2017.09.06 at 14:52 +0200, Thomas Gleixner wrote:
> > > > On Tue, 5 Sep 2017, Markus Trippelsdorf wrote:
> > > > > On 2017.09.05 at 10:53 +0200, Peter Zijlstra wrote:
> > > > > > > Any ideas on how to debug this further?
> > > > > > 
> > > > > > So you have a (real) serial line on that box?
> > > > > 
> > > > > Sadly, no. But hopefully somebody else (with a proper kernel debugging
> > > > > setup) will reproduce the issue soon.
> > > > 
> > > > Does the machine respond to ping or is it entirely dead?
> > > 
> > > It is entirely dead and doesn't respond to ping.
> > 
> > The bug even kills the host (running 4.13) when running 24e700e2 in qemu
> > (kvm) and compiling stuff in parallel in the guest.
> > I see an RCU CPU stall in dmesg (on the host), but unfortunately cannot
> > save it, because nothing gets written to disk after the stall.
> > Connecting to qemu via gdb also doesn't work.
> 
> My guess would be a bug in a low level function (asm) that only hits AMD
> machines. I'm running an old Phenom II X4 processor. My config is
> attached.
> 
> -- 
> Markus
>