Is it possible to "freeze" Tumbleweed on Kernel 4.11.8 while updating other packages through zipper? I usually do a zipper dup - how can I avoid that kernel 4.12.x is installed?

I have severe problems with Kernel 4.12.7 and 4.12.8 - both kernels corrupt the graphical system during boot, I did not manage to get Nouveau working, and the legacy NVidia driver .340 fails to compile and install. While trying to find a solution I nearly broke my system and only managed to safe the installation through reviving a snapshot ...

While I find several posts on issues in relation to NVidia cards and Kernel 4.12.x through Google, it seems not many openSuse users have this problem ... Maybe it is really linked to the NVidia NVS 3100m series. Still, I hope that someone is working on this issue.

For the time being I need to stay with 4.11.x (or 4.11.8). How can I do this?