We are running a survey to help us improve the experience for all of our members. If you see the survey appear, please take the time to tell us about your experience if you can.
This question was raised in the 'How to implement a secure IoT system on ARMv8-M' webinar, view all the questions in the round up blog post.
There are separate stacks for the secure and non-secure code. These register values will be pushed onto the secure stack so they won't be exposed to the non-secure code.