Comment # 2 on bug 1120317 from Theodor M�ller

a new kernel update point me to the problem
in /var/log/zypp/history i found
# Creating initrd: /boot/initrd-4.12.14-lp150.12.45-default
# dracut: Executing: /usr/bin/dracut --logfile /var/log/YaST2/mkinitrd.log
--force /boot/initrd-4.12.14-lp150.12.45-default 4.12.14-lp150.12.45-default
# dracut: *** Including module: bash ***
# dracut: *** Including module: systemd ***
# dracut: *** Including module: warpclock ***
# dracut: *** Including module: systemd-initrd ***
# dracut: *** Including module: i18n ***
# dracut: Could not find FONT_MAP none!
# dracut: *** Including module: drm ***
# dracut: Possible missing firmware "amdgpu/polaris12_k_mc.bin" for kernel
module "amdgpu.ko"
# dracut: Possible missing firmware "amdgpu/polaris10_k_mc.bin" for kernel
module "amdgpu.ko"
# dracut: Possible missing firmware "amdgpu/polaris11_k_mc.bin" for kernel
module "amdgpu.ko"


the amd amdgtpu-pro-18.50 driver installation script installed the firmware
files in the directory /usr/source/amdgpu-18.50.708487/amdgpu/
during zypper kernel update the firmware files are read from
/lib/firmware/amdgpu/
manual copy the firmware files from /usr/source/.... to /lib/firmware/amdgpu
and running 
/usr/bin/dracut --logfile /var/log/YaST2/mkinitrd.log --force
/boot/initrd-4.12.14-lp150.12.28-default 4.12.14-lp150.12.28-default
fixed the problerm

please close the record