Comment # 4 on bug 1219444 from Takashi Iwai

Yes, the lack of KMP is a known issue with the TW kernel build for Leap,
unfortunately.

Honestly speaking, fixing this kind of bug for amdgpu on SLE15-SP5 kernel is
really tough.  It seems hitting on only certain models / hardware configs.

You may try Leap 15.6 kernel instead of TW backport kernel, too; which should
be new enough and receive most of fixes from the latest code, too.  vbox driver
should be available for Leap 15.6, too.  But maybe some later point after the
kABI freeze.