Re: Guest OS becomes totally unresponsive when running on VMware

[Lukas Straub]

On Sat, 30 Jan 2021 14:28:08 +0100
Salvatore Mazzarino <apocalipse89@gmail.com> wrote:

> I'm running QEMU v4.2.0 inside a Docker container. The Docker container runs 
> on a VMware VM running Flatcar Linux OS with kernel version 5.4.92. It 
> happens that the QEMU process starts to show up an high usage of CPU. The 
> CPUs that the Qemu process uses go into saturation and the guest OS running 
> by QEMU becomes totally unresponsive. Note that this issue does not occur 
> when QEMU runs on a bare metal machine. It only happens when we have nested 
> virtualization. 
> 
> I would like to debug the QEMU process to get where it get stuck. Then I 
> compiled a version with tracing enabled. Following the tracing doc I was able 
> to get traces of QEMU. 
> 
> Problem here is that I'm not sure exactly what function to trace. If I trace 
> all the file is huge. In 5 seconds of tracing in fact I get over 2GB. I would 
> need some guidance to narrow down the issue finding the right QEMU trace to 
> get some useful info. Which function would you recommend to trace? 
> 

I'd first check if nested virtualization works at all in the guest and the 
docker container.

--

pgpLz0yDAbCTC.pgp
Description: OpenPGP digital signature