Comment 52 for bug 1413540

@baco-1

1) What kind of hardware are you running on L0? ('ubuntu-bug linux' and filing a bug would collect the necessary info)
2) What kind of load are you seeing in L0, L1?
3) Can you give me the output of 'tail /sys/module/kvm_intel/parameters/*' ?
4) You could setup crashdump to dump on a hang (if we think its the right one), or just have a full backtrace on a softlockup by adding the following to the kernel cmdline:
softlockup_all_cpu_backtrace=1

Having a single vCPU could either be reducing the load, or avoiding a race; it would be hard to tell without a proper backtrace of the hang itsself.

This seems like a pretty simple testcase, I will put it on my list of things to try and reproduce.