device: 0.852
other: 0.839
graphic: 0.814
instruction: 0.722
socket: 0.697
network: 0.685
semantic: 0.663
vnc: 0.640
assembly: 0.620
KVM: 0.487
boot: 0.464
mistranslation: 0.266

Changing CD ROM medium sometimes fails with 'Tray of device is not open'
Description of problem:
QEMU reports that a CD ROM tray is not open when exchanging media:
`unable to execute QEMU command 'blockdev-remove-medium': Tray of device 'ide0-1-0' is not open`

We see the issue in upstream libvirt integration tests. However, this issue is a race and the reproducibility rate is <15%.
Steps to reproduce:
On the high level this is what we do:
1. eject medium that the machine was started with
2. insert a different medium into the CD ROM

Translating the above to QEMU QMP commands this is what the test exercises:
1. blockdev-open-tray
2. blockdev-remove-medium
3. blockdev-del
4. blockdev-close-tray
5. blockdev-open-tray
6. blockdev-remove-medium
7. blockdev-add
8. blockdev-insert-medium <<< This is where the test fails
9. blockdev-close-tray
Additional information:
I bisected the code (3 times just to be sure since it's a race) and the following commit fell out of it:
55adb3c45620c31f29978f209e2a44a08d34e2da

I'm attaching QEMU trace events and a bunch of libvirt test logs (good and bad for comparison). If you think of anything else I should provide in order to help with the issue analysis, please let me know what other option should be turned on.[qemu_traces.tar.gz](/uploads/32e48c92efce3484e552df063795af4d/qemu_traces.tar.gz)