Cannot read the structure of Hardware Feedback Interface and ThreadDirector in the memory

y4nx1ang — Tue, 29 Aug 2023 07:10:09 GMT

According to the Intel Manual Vol. 3A/B chatpter 15.6: the Hardware Feedback Interface and Intel® Thread Director both have a structure in memory to record some information changes of the CPU. However, I couldn’t find any information about the content of that memory region being '0'.

The manual says that the memory region's address is in :

and the MAXPHYADDR can be found from

2. I have an i7-12700 CPU and the maxphyaddr is '46'. I obtained the physical address of the Hardware Feedback Interface and Thread Director structure and attempted to read it from a kernel module. However, the content of that memory region appears to be all '0'. I have ensured that both the HFI and Thread Director have been enabled.

Is there any method to deal with this? Thanks!

topic Cannot read the structure of Hardware Feedback Interface and ThreadDirector in the memory in Software Tuning, Performance Optimization & Platform Monitoring

Cannot read the structure of Hardware Feedback Interface and ThreadDirector in the memory