High CPU from ntoskrnl.exe during idle on GetStackLimits
I found the answer to my problem a long time ago, but forgot to add it in here.
It was the maintenance functionality in Windows 10 called:
RunFullMemoryDiagnostic
Found under:
\Microsoft\Windows\MemoryDiagnostic
After disabling this my maintenance tasks can finish instead of just using CPU on this task.
I do not have any memory problems or BSODs lately, but I do have 32GB of memory, which might play a role for this task to finish.
I did run it for some hours, but it never finished, so I am much better off without it.
Thank you for the help though!