Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm fixes from Dan Williams:
 "Several fixes to the DSM (ACPI device specific method) marshaling
  implementation.

  I consider these urgent enough to send for 4.9 consideration since
  they fix the kernel's handling of ARS (Address Range Scrub) commands.
  Especially for platforms without machine-check-recovery capabilities,
  successful execution of ARS commands enables the platform to
  potentially break out of an infinite reboot problem if a media error
  is present in the boot path. There is also a one line fix for a
  device-dax read-only mapping regression.

  Commits 9a901f54 ("acpi, nfit: fix extended status translations
  for ACPI DSMs") and 325896ff ("device-dax: fix private mapping
  restriction, permit read-only") are true regression fixes for changes
  introduced this cycle.

  Commit efda1b5d ("acpi, nfit, libnvdimm: fix / harden ars_status
  output length handling") fixes the kernel's handling of zero-length
  results, this never would have worked in the past, but we only just
  recently discovered a BIOS implementation that emits this arguably
  spec non-compliant result.

  The remaining two commits are additional fall out from thinking
  through the implications of a zero / truncated length result of the
  ARS Status command.

  In order to mitigate the risk that these changes introduce yet more
  regressions they are backstopped by a new unit test in commit
  a7de92da ("tools/testing/nvdimm: unit test acpi_nfit_ctl()") that
  mocks up inputs to acpi_nfit_ctl()"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  device-dax: fix private mapping restriction, permit read-only
  tools/testing/nvdimm: unit test acpi_nfit_ctl()
  acpi, nfit: fix bus vs dimm confusion in xlat_status
  acpi, nfit: validate ars_status output buffer size
  acpi, nfit, libnvdimm: fix / harden ars_status output length handling
  acpi, nfit: fix extended status translations for ACPI DSMs