other: 0.148
device: 0.138
boot: 0.116
PID: 0.077
files: 0.072
semantic: 0.071
performance: 0.067
socket: 0.061
vnc: 0.056
debug: 0.046
graphic: 0.046
network: 0.041
permissions: 0.035
KVM: 0.028
boot: 0.478
debug: 0.318
performance: 0.046
other: 0.026
files: 0.024
PID: 0.023
socket: 0.023
graphic: 0.018
semantic: 0.010
network: 0.009
vnc: 0.009
device: 0.008
permissions: 0.004
KVM: 0.004

qemu-system-x86_64 kernel panic 30% of the time starting up VM

I have created a Fedora Core 5 x86_64 VM image. When I run the image using QEMU on Windows the VM hangs while loading the kernel about 30% of the time. I am trying to use this VM with a CI software, looking at the history the build failed 27 out of 79 attempts. QEMU 3.0.0 is installed on the CI machine. I have tried using the exact same image using QEMU on Linux (Ubuntu) and found the image boot successful every time (40+ attempts). The VM image is fairly old it was created using QEMU 0.11.1.

I have tried multiple versions on QEMU on windows; 0.11.1, 2.12.1, and 3.0.0 all of them fail randomly. I can reproduce the issue on several different Windows 10 computers.

The command I am using to start the VM is “qemu-system-x86_64.exe -cpu qemu64 -smp cores=2 -device e1000,netdev=net0 -boot menu=off -m 1G -drive `"file=C:\qimages\Fedora-Core-5-x64.qcow2,index=0,media=disk`" -snapshot -netdev user,id=net0,hostfwd=tcp::10022-:22”

I can provide the qcow image but it is somewhat large coming it at 4.15GB so I’m not sure what would be the best way to transfer it.



Is this using TCG (i.e. emulation) rather than Hyper V virtualisation?

There are problems reliable booting the VM using TCG, HAXM, and Hyper-V. TCG fails the least often. Attached is a pic of the error using HAXM, a lot of "BUG: soft lockup detect on CPU#x!". 

I tried to add logging but nothing ever shows up in the log file. I tried adding "-d cpu,guest_errors -D E:\log.txt" to the command but the log file is always empty.

The QEMU project is currently considering to move its bug tracking to
another system. For this we need to know which bugs are still valid
and which could be closed already. Thus we are setting older bugs to
"Incomplete" now.

If you still think this bug report here is valid, then please switch
the state back to "New" within the next 60 days, otherwise this report
will be marked as "Expired". Or please mark it as "Fix Released" if
the problem has been solved with a newer version of QEMU already.

Thank you and sorry for the inconvenience.


[Expired for QEMU because there has been no activity for 60 days.]