libnvdimm for 4.6 1/ Asynchronous address range scrub: Given the capacities of next generation persistent memory devices a scrub operation to find all poison may take 10s of seconds. We want this scrub work to be done asynchronously with the rest of system initialization, so we move it out of line from the NFIT probing, i.e. acpi_nfit_add(). 2/ Clear poison: ACPI 6.1 introduces the ability to send "clear error" commands to the ACPI0012:00 device representing the root of an "nvdimm bus". Similar to relocating a bad block on a disk, this support clears media errors in response to a write. 3/ Persistent memory resource tracking: A persistent memory range may be designated as simply "reserved" by platform firmware in the efi/e820 memory map. Later when the NFIT driver loads it discovers that the range is "Persistent Memory". The NFIT bus driver inserts a resource to advertise that "persistent" attribute in the system resource tree for /proc/iomem and kernel-internal usages. 4/ Miscellaneous cleanups and fixes: Workaround section misaligned pmem ranges when allocating a struct page memmap, fix handling of the read-only case in the ioctl path, and clean up block device major number allocation.