Description of problem:

After booting a fresh system with NVDIMM devices, trying to run 'ndctl list -N' will hang.
No pmem devices will appear in the system ('lsblk' doesn't list them).

This was investigated and found related to address-range-scrub process performed by the NVDIMM/NFIT kernel driver. The process takes a long time (usually times out after 90 seconds for each NVDIMM, may take more that 20 minutes for a large amount of devices) and during it, NVDIMM driver and devices are not accessible.

Version-Release number of selected component (if applicable):
ndctl version 56
kernel version 3.10.0-693

How reproducible:
Boot system with NVDIMMs
Login to prompt
Run 'ndctl list -N'

Actual results:
The command will be stuck.


Expected results:
The command should return "busy" or a list of nvdimm devices.


Additional info:
There are linux kernel patches proposed here:
https://www.spinics.net/lists/linux-acpi/msg81584.html
That should mitigate this issue.