Comment # 1 on bug 1203968 from Takashi Iwai

Could you check the behavior with the latest SLE15-SP4 git build?  The kernel
package is available at OBS Kernel:SLE15-SP4 repo,
  http://download.opensuse.org/repositories/Kernel:/SLE15-SP4/pool/

Note that it's an official build, hence Secure Boot needs to be disabled.