After some investigation, it appears that if I upgrade the Linux kernel package first, then the upgrade works, like this: sed -i s/stretch/sid/ /etc/apt/sources.list apt-get update apt-get install linux-image-amd64 apt-get dist-upgrade If I just do apt-get dist-upgrade, then the bug is triggered. So my idea is that probably, adding a versionned breaks: somewhere will fix the upgrade problem. Let's see if I can find out... Cheers, Thomas Goirand (zigo)