There are a number of mechanisms at work for such use cases. You can flush caches manually, or have the memory uncached, also you need to make sure, some access

There are a number of mechanisms at work for such use cases. You can flush caches manually, or have the memory uncached, also you need to make sure, some accesses don't reorder. If you are interested, you might search i.e. for ARM device memory. https://www.embedded.com/dealing-with-memory-access-ordering-in-complex-embedded-designs/ https://www.embedded.com/dealing-with-memory-access-ordering...