Change in USB Handling for KVM betweeen kernels 4.9.0-5 and 4.14.0-2 ?

[Erwan David <erwan@rail.eu.org>]

I have a QEMU/KVM virtual machine on which I linked a USB device.

I use testing, however with the 4.14.0-2 of testing, the VM does not
start because it cannot access the USB device. Running the same testing
userland, but with kernel 4.9.0-5 from stable, everything works. What
could be the reason, which setting should I change ?

Thanks.