Commit Graph

83 Commits

Author SHA1 Message Date
Wan Jiabing 681865a03d libnvdimm: Remove duplicate struct declaration
struct device is declared at 133rd line. The second declaration is
unnecessary, remove it.

Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Link: https://lore.kernel.org/r/20210419112725.42145-1-wanjiabing@vivo.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-05-12 12:37:14 -07:00
Dan Williams a1facc1fff ACPI: NFIT: Add runtime firmware activate support
Plumb the platform specific backend for the generic libnvdimm firmware
activate interface. Register dimm level operations to arm/disarm
activation, and register bus level operations to report the dynamic
platform-quiesce time relative to the number of dimms armed for firmware
activation.

A new nfit-specific bus attribute "firmware_activate_noidle" is added to
allow the activation to switch between platform enforced, and OS
opportunistic device quiesce. In other words, let the hibernate cycle
handle in-flight device-dma rather than the platform attempting to
increase PCI-E timeouts and the like.

Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2020-07-28 19:29:22 -06:00
Dan Williams 48001ea50d PM, libnvdimm: Add runtime firmware activation support
Abstract platform specific mechanics for nvdimm firmware activation
behind a handful of generic ops. At the bus level ->activate_state()
indicates the unified state (idle, busy, armed) of all DIMMs on the bus,
and ->capability() indicates the system state expectations for activate.
At the DIMM level ->activate_state() indicates the per-DIMM state,
->activate_result() indicates the outcome of the last activation
attempt, and ->arm() attempts to transition the DIMM from 'idle' to
'armed'.

A new hibernate_quiet_exec() facility is added to support firmware
activation in an OS defined system quiesce state. It leverages the fact
that the hibernate-freeze state wants to assert that a memory
hibernation snapshot can be taken. This is in contrast to a platform
firmware defined quiesce state that may forcefully quiet the memory
controller independent of whether an individual device-driver properly
supports hibernate-freeze.

The libnvdimm sysfs interface is extended to support detection of a
firmware activate capability. The mechanism supports enumeration and
triggering of firmware activate, optionally in the
hibernate_quiet_exec() context.

[rafael: hibernate_quiet_exec() proposal]
[vishal: fix up sparse warning, grammar in Documentation/]

Cc: Pavel Machek <pavel@ucw.cz>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Co-developed-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2020-07-28 19:28:32 -06:00
Dan Williams d46e6a2176 ACPI: NFIT: Move bus_dsm_mask out of generic nvdimm_bus_descriptor
DSMs are strictly an ACPI mechanism, evict the bus_dsm_mask concept from
the generic 'struct nvdimm_bus_descriptor' object.

As a side effect the test facility ->bus_nfit_cmd_force_en is no longer
necessary. The test infrastructure can communicate that information
directly in ->bus_dsm_mask.

Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2020-07-25 19:34:47 -06:00
Dan Williams 92fe2aa859 libnvdimm: Validate command family indices
The ND_CMD_CALL format allows for a general passthrough of passlisted
commands targeting a given command set. However there is no validation
of the family index relative to what the bus supports.

- Update the NFIT bus implementation (the only one that supports
  ND_CMD_CALL passthrough) to also passlist the valid set of command
  family indices.

- Update the generic __nd_ioctl() path to validate that field on behalf
  of all implementations.

Fixes: 31eca76ba2 ("nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism")
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2020-07-25 19:34:47 -06:00
Dan Williams a0e374525d libnvdimm/region: Introduce NDD_LABELING
The NDD_ALIASING flag is used to indicate where pmem capacity might
alias with blk capacity and require labeling. It is also used to
indicate whether the DIMM supports labeling. Separate this latter
capability into its own flag so that the NDD_ALIASING flag is scoped to
true aliased configurations.

To my knowledge aliased configurations only exist in the ACPI spec,
there are no known platforms that ship this support in production.

This clarity allows namespace-capacity alignment constraints around
interleave-ways to be relaxed.

Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/158041477856.3889308.4212605617834097674.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2020-03-17 12:23:21 -07:00
Dan Williams e755799aef libnvdimm: Move nvdimm_bus_attribute_group to device_type
A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nvdimm_bus_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309903815.1582359.6418211876315050283.stgit@dwillia2-desk3.amr.corp.intel.com
2019-11-19 09:52:12 -08:00
Dan Williams 360eba7ebd libnvdimm: Move nvdimm_attribute_group to device_type
A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nvdimm_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309903201.1582359.10966209746585062329.stgit@dwillia2-desk3.amr.corp.intel.com
2019-11-19 09:52:12 -08:00
Dan Williams 4ce79fa97e libnvdimm: Move nd_mapping_attribute_group to device_type
A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nd_mapping_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309902686.1582359.6749533709859492704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-11-19 09:52:12 -08:00
Dan Williams 7c4fc8cde1 libnvdimm: Move nd_region_attribute_group to device_type
A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nd_region_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309902169.1582359.16828508538444551337.stgit@dwillia2-desk3.amr.corp.intel.com
2019-11-19 09:52:12 -08:00
Dan Williams e2f6a0e348 libnvdimm: Move nd_numa_attribute_group to device_type
A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nd_numa_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157401269537.43284.14411189404186877352.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-11-19 09:51:54 -08:00
Dan Williams adbb68293f libnvdimm: Move nd_device_attribute_group to device_type
A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nd_device_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

For regions this creates a new nd_region_attribute_groups[] added to the
per-region device-type instances.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309901138.1582359.12909354140826530394.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-11-17 09:17:39 -08:00
Dan Williams d78c620a2e libnvdimm/security: Introduce a 'frozen' attribute
In the process of debugging a system with an NVDIMM that was failing to
unlock it was found that the kernel is reporting 'locked' while the DIMM
security interface is 'frozen'. Unfortunately the security state is
tracked internally as an enum which prevents it from communicating the
difference between 'locked' and 'locked + frozen'. It follows that the
enum also prevents the kernel from communicating 'unlocked + frozen'
which would be useful for debugging why security operations like 'change
passphrase' are disabled.

Ditch the security state enum for a set of flags and introduce a new
sysfs attribute explicitly for the 'frozen' state. The regression risk
is low because the 'frozen' state was already blocked behind the
'locked' state, but will need to revisit if there were cases where
applications need 'frozen' to show up in the primary 'security'
attribute. The expectation is that communicating 'frozen' is mostly a
helper for debug and status monitoring.

Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reported-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Link: https://lore.kernel.org/r/156686729474.184120.5835135644278860826.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-08-29 13:49:13 -07:00
Pankaj Gupta fefc1d97fa libnvdimm: add dax_dev sync flag
This patch adds 'DAXDEV_SYNC' flag which is set
for nd_region doing synchronous flush. This later
is used to disable MAP_SYNC functionality for
ext4 & xfs filesystem for devices don't support
synchronous flush.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-07-05 15:19:10 -07:00
Pankaj Gupta c5d4355d10 libnvdimm: nd_region flush callback support
This patch adds functionality to perform flush from guest
to host over VIRTIO. We are registering a callback based
on 'nd_region' type. virtio_pmem driver requires this special
flush function. For rest of the region types we are registering
existing flush function. Report error returned by host fsync
failure to userspace.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-07-05 15:19:10 -07:00
Thomas Gleixner 5b497af42f treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of version 2 of the gnu general public license as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 64 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.894819585@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:38 +02:00
Linus Torvalds f67e3fb489 device-dax for 5.1
* Replace the /sys/class/dax device model with /sys/bus/dax, and include
   a compat driver so distributions can opt-in to the new ABI.
 
 * Allow for an alternative driver for the device-dax address-range
 
 * Introduce the 'kmem' driver to hotplug / assign a device-dax
   address-range to the core-mm.
 
 * Arrange for the device-dax target-node to be onlined so that the newly
   added memory range can be uniquely referenced by numa apis.
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Merge tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull device-dax updates from Dan Williams:
 "New device-dax infrastructure to allow persistent memory and other
  "reserved" / performance differentiated memories, to be assigned to
  the core-mm as "System RAM".

  Some users want to use persistent memory as additional volatile
  memory. They are willing to cope with potential performance
  differences, for example between DRAM and 3D Xpoint, and want to use
  typical Linux memory management apis rather than a userspace memory
  allocator layered over an mmap() of a dax file. The administration
  model is to decide how much Persistent Memory (pmem) to use as System
  RAM, create a device-dax-mode namespace of that size, and then assign
  it to the core-mm. The rationale for device-dax is that it is a
  generic memory-mapping driver that can be layered over any "special
  purpose" memory, not just pmem. On subsequent boots udev rules can be
  used to restore the memory assignment.

  One implication of using pmem as RAM is that mlock() no longer keeps
  data off persistent media. For this reason it is recommended to enable
  NVDIMM Security (previously merged for 5.0) to encrypt pmem contents
  at rest. We considered making this recommendation an actively enforced
  requirement, but in the end decided to leave it as a distribution /
  administrator policy to allow for emulation and test environments that
  lack security capable NVDIMMs.

  Summary:

   - Replace the /sys/class/dax device model with /sys/bus/dax, and
     include a compat driver so distributions can opt-in to the new ABI.

   - Allow for an alternative driver for the device-dax address-range

   - Introduce the 'kmem' driver to hotplug / assign a device-dax
     address-range to the core-mm.

   - Arrange for the device-dax target-node to be onlined so that the
     newly added memory range can be uniquely referenced by numa apis"

NOTE! I'm not entirely happy with the whole "PMEM as RAM" model because
we currently have special - and very annoying rules in the kernel about
accessing PMEM only with the "MC safe" accessors, because machine checks
inside the regular repeat string copy functions can be fatal in some
(not described) circumstances.

And apparently the PMEM modules can cause that a lot more than regular
RAM.  The argument is that this happens because PMEM doesn't necessarily
get scrubbed at boot like RAM does, but that is planned to be added for
the user space tooling.

Quoting Dan from another email:
 "The exposure can be reduced in the volatile-RAM case by scanning for
  and clearing errors before it is onlined as RAM. The userspace tooling
  for that can be in place before v5.1-final. There's also runtime
  notifications of errors via acpi_nfit_uc_error_notify() from
  background scrubbers on the DIMM devices. With that mechanism the
  kernel could proactively clear newly discovered poison in the volatile
  case, but that would be additional development more suitable for v5.2.

  I understand the concern, and the need to highlight this issue by
  tapping the brakes on feature development, but I don't see PMEM as RAM
  making the situation worse when the exposure is also there via DAX in
  the PMEM case. Volatile-RAM is arguably a safer use case since it's
  possible to repair pages where the persistent case needs active
  application coordination"

* tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  device-dax: "Hotplug" persistent memory for use like normal RAM
  mm/resource: Let walk_system_ram_range() search child resources
  mm/memory-hotplug: Allow memory resources to be children
  mm/resource: Move HMM pr_debug() deeper into resource code
  mm/resource: Return real error codes from walk failures
  device-dax: Add a 'modalias' attribute to DAX 'bus' devices
  device-dax: Add a 'target_node' attribute
  device-dax: Auto-bind device after successful new_id
  acpi/nfit, device-dax: Identify differentiated memory with a unique numa-node
  device-dax: Add /sys/class/dax backwards compatibility
  device-dax: Add support for a dax override driver
  device-dax: Move resource pinning+mapping into the common driver
  device-dax: Introduce bus + driver model
  device-dax: Start defining a dax bus model
  device-dax: Remove multi-resource infrastructure
  device-dax: Kill dax_region base
  device-dax: Kill dax_region ida
2019-03-16 13:05:32 -07:00
Dan Williams 451fed24e9 Merge branch 'for-5.1/libnvdimm' into libnvdimm-for-next
Merge miscellaneous libnvdimm sub-system updates for v5.1. Highlights
include:

* Support for the Hyper-V family of device-specific-methods (DSMs)
* Several fixes and workarounds for Hyper-V compatibility.
* Fix for the support to cache the dirty-shutdown-count at init.
2019-03-11 12:13:42 -07:00
Dan Williams d5d30d5a5c libnvdimm/dimm: Add a no-BLK quirk based on NVDIMM family
As Dexuan reports the NVDIMM_FAMILY_HYPERV platform is incompatible with
the existing Linux namespace implementation because it uses
NSLABEL_FLAG_LOCAL for x1-width PMEM interleave sets. Quirk it as an
platform / DIMM that does not provide BLK-aperture access. Allow the
libnvdimm core to assume no potential for aliasing. In case other
implementations make the same mistake, provide a "noblk" module
parameter to force-enable the quirk.

Link: https://lkml.kernel.org/r/PU1P153MB0169977604493B82B662A01CBF920@PU1P153MB0169.APCP153.PROD.OUTLOOK.COM
Reported-by: Dexuan Cui <decui@microsoft.com>
Tested-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-02 16:35:26 -08:00
Dan Williams 1cd7386549 libnvdimm/security: Require nvdimm_security_setup_events() to succeed
The following warning:

    ACPI0012:00: security event setup failed: -19

...is meant to capture exceptional failures of sysfs_get_dirent(),
however it will also fail in the common case when security support is
disabled. A few issues:

1/ A dev_warn() report for a common case is too chatty
2/ The setup of this notifier is generic, no need for it to be driven
   from the nfit driver, it can exist completely in the core.
3/ If it fails for any reason besides security support being disabled,
   that's fatal and should abort DIMM activation. Userspace may hang if
   it never gets overwrite notifications.
4/ The dirent needs to be released.

Move the call to the core 'dimm' driver, make it conditional on security
support being active, make it fatal for the exceptional case, add the
missing sysfs_put() at device disable time.

Fixes: 7d988097c5 ("...Add security DSM overwrite support")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-21 09:57:43 -08:00
Dan Williams 1cb95e072e libnvdimm/dimm: Fix security capability detection for non-Intel NVDIMMs
Kees reports a crash with the following signature...

 RIP: 0010:nvdimm_visible+0x79/0x80
 [..]
 Call Trace:
  internal_create_group+0xf4/0x380
  sysfs_create_groups+0x46/0xb0
  device_add+0x331/0x680
  nd_async_device_register+0x15/0x60
  async_run_entry_fn+0x38/0x100

...when starting a QEMU environment with "label-less" DIMM. Without
labels QEMU does not publish any DSM methods. Without defined methods
the NVDIMM_FAMILY type is not established and the nfit driver will skip
registering security operations.

In that case the security state should be initialized to a negative
value in __nvdimm_create() and nvdimm_visible() should skip
interrogating the specific ops. However, since 'enum
nvdimm_security_state' was only defined to contain positive values the
"if (nvdimm->sec.state < 0)" check always fails.

Define a negative error state to allow negative state values to be
handled as expected.

Fixes: f298939655 ("acpi/nfit, libnvdimm: Introduce nvdimm_security_ops")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reported-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-08 22:06:09 -08:00
Dan Williams 8fc5c73554 acpi/nfit, device-dax: Identify differentiated memory with a unique numa-node
Persistent memory, as described by the ACPI NFIT (NVDIMM Firmware
Interface Table), is the first known instance of a memory range
described by a unique "target" proximity domain. Where "initiator" and
"target" proximity domains is an approach that the ACPI HMAT
(Heterogeneous Memory Attributes Table) uses to described the unique
performance properties of a memory range relative to a given initiator
(e.g. CPU or DMA device).

Currently the numa-node for a /dev/pmemX block-device or /dev/daxX.Y
char-device follows the traditional notion of 'numa-node' where the
attribute conveys the closest online numa-node. That numa-node attribute
is useful for cpu-binding and memory-binding processes *near* the
device. However, when the memory range backing a 'pmem', or 'dax' device
is onlined (memory hot-add) the memory-only-numa-node representing that
address needs to be differentiated from the set of online nodes. In
other words, the numa-node association of the device depends on whether
you can bind processes *near* the cpu-numa-node in the offline
device-case, or bind process *on* the memory-range directly after the
backing address range is onlined.

Allow for the case that platform firmware describes persistent memory
with a unique proximity domain, i.e. when it is distinct from the
proximity of DRAM and CPUs that are on the same socket. Plumb the Linux
numa-node translation of that proximity through the libnvdimm region
device to namespaces that are in device-dax mode. With this in place the
proposed kmem driver [1] can optionally discover a unique numa-node
number for the address range as it transitions the memory from an
offline state managed by a device-driver to an online memory range
managed by the core-mm.

[1]: https://lore.kernel.org/lkml/20181022201317.8558C1D8@viggo.jf.intel.com

Reported-by: Fan Du <fan.du@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-06 21:41:57 -08:00
Dave Jiang 89fa9d8ea7 acpi/nfit, libnvdimm/security: add Intel DSM 1.8 master passphrase support
With Intel DSM 1.8 [1] two new security DSMs are introduced. Enable/update
master passphrase and master secure erase. The master passphrase allows
a secure erase to be performed without the user passphrase that is set on
the NVDIMM. The commands of master_update and master_erase are added to
the sysfs knob in order to initiate the DSMs. They are similar in opeartion
mechanism compare to update and erase.

[1]: http://pmem.io/documents/NVDIMM_DSM_Interface-V1.8.pdf

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-21 12:44:41 -08:00
Dave Jiang 7d988097c5 acpi/nfit, libnvdimm/security: Add security DSM overwrite support
Add support for the NVDIMM_FAMILY_INTEL "ovewrite" capability as
described by the Intel DSM spec v1.7. This will allow triggering of
overwrite on Intel NVDIMMs. The overwrite operation can take tens of
minutes. When the overwrite DSM is issued successfully, the NVDIMMs will
be unaccessible. The kernel will do backoff polling to detect when the
overwrite process is completed. According to the DSM spec v1.7, the 128G
NVDIMMs can take up to 15mins to perform overwrite and larger DIMMs will
take longer.

Given that overwrite puts the DIMM in an indeterminate state until it
completes introduce the NDD_SECURITY_OVERWRITE flag to prevent other
operations from executing when overwrite is happening. The
NDD_WORK_PENDING flag is added to denote that there is a device reference
on the nvdimm device for an async workqueue thread context.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-21 12:44:41 -08:00
Dave Jiang 64e77c8c04 acpi/nfit, libnvdimm: Add support for issue secure erase DSM to Intel nvdimm
Add support to issue a secure erase DSM to the Intel nvdimm. The
required passphrase is acquired from an encrypted key in the kernel user
keyring. To trigger the action, "erase <keyid>" is written to the
"security" sysfs attribute.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-21 12:44:41 -08:00
Dave Jiang 03b65b22ad acpi/nfit, libnvdimm: Add disable passphrase support to Intel nvdimm.
Add support to disable passphrase (security) for the Intel nvdimm. The
passphrase used for disabling is pulled from an encrypted-key in the kernel
user keyring. The action is triggered by writing "disable <keyid>" to the
sysfs attribute "security".

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-21 12:44:41 -08:00
Dave Jiang 4c6926a23b acpi/nfit, libnvdimm: Add unlock of nvdimm support for Intel DIMMs
Add support to unlock the dimm via the kernel key management APIs. The
passphrase is expected to be pulled from userspace through keyutils.
The key management and sysfs attributes are libnvdimm generic.

Encrypted keys are used to protect the nvdimm passphrase at rest. The
master key can be a trusted-key sealed in a TPM, preferred, or an
encrypted-key, more flexible, but more exposure to a potential attacker.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-13 17:54:13 -08:00
Dave Jiang 37833fb798 acpi/nfit, libnvdimm: Add freeze security support to Intel nvdimm
Add support for freeze security on Intel nvdimm. This locks out any
changes to security for the DIMM until a hard reset of the DIMM is
performed. This is triggered by writing "freeze" to the generic
nvdimm/nmemX "security" sysfs attribute.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-13 17:54:13 -08:00
Dave Jiang f298939655 acpi/nfit, libnvdimm: Introduce nvdimm_security_ops
Some NVDIMMs, like the ones defined by the NVDIMM_FAMILY_INTEL command
set, expose a security capability to lock the DIMMs at poweroff and
require a passphrase to unlock them. The security model is derived from
ATA security. In anticipation of other DIMMs implementing a similar
scheme, and to abstract the core security implementation away from the
device-specific details, introduce nvdimm_security_ops.

Initially only a status retrieval operation, ->state(), is defined,
along with the base infrastructure and definitions for future
operations.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-13 17:54:13 -08:00
Dave Jiang d6548ae4d1 acpi/nfit, libnvdimm: Store dimm id as a member to struct nvdimm
The generated dimm id is needed for the sysfs attribute as well as being
used as the identifier/description for the security key. Since it's
constant and should never change, store it as a member of struct nvdimm.

As nvdimm_create() continues to grow parameters relative to NFIT driver
requirements, do not require other implementations to keep pace.
Introduce __nvdimm_create() to carry the new parameters and keep
nvdimm_create() with the long standing default api.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-13 17:54:12 -08:00
Dave Jiang b3ed2ce024 acpi/nfit: Add support for Intel DSM 1.8 commands
Add command definition for security commands defined in Intel DSM
specification v1.8 [1]. This includes "get security state", "set
passphrase", "unlock unit", "freeze lock", "secure erase", "overwrite",
"overwrite query", "master passphrase enable/disable", and "master
erase", . Since this adds several Intel definitions, move the relevant
bits to their own header.

These commands mutate physical data, but that manipulation is not cache
coherent. The requirement to flush and invalidate caches makes these
commands unsuitable to be called from userspace, so extra logic is added
to detect and block these commands from being submitted via the ioctl
command submission path.

Lastly, the commands may contain sensitive key material that should not
be dumped in a standard debug session. Update the nvdimm-command
payload-dump facility to move security command payloads behind a
default-off compile time switch.

[1]: http://pmem.io/documents/NVDIMM_DSM_Interface-V1.8.pdf

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-04 10:31:11 -08:00
Oliver O'Halloran 1ff19f487a libnvdimm: Add of_node to region and bus descriptors
We want to be able to cross reference the region and bus devices
with the device tree node that they were spawned from. libNVDIMM
handles creating the actual devices for these internally, so we
need to pass in a pointer to the relevant node in the descriptor.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-04-07 07:53:23 -07:00
Dan Williams 243f29fe44 libnvdimm: add an api to cast a 'struct nd_region' to its 'struct device'
For debug, it is useful for bus providers to be able to retrieve the
'struct device' associated with an nd_region instance that it
registered. We already have to_nd_region() to perform the reverse cast
operation, in fact its duplicate declaration can be removed from the
private drivers/nvdimm/nd.h header.

Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-04-03 11:51:42 -07:00
Dave Jiang 30e6d7bf29 acpi: nfit: add persistent memory control flag for nd_region
Propagate the ADR attribute flag from the NFIT platform capabilities
sub-table to nd_region.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
2018-02-01 15:01:15 -07:00
Dave Jiang 06e8ccdab1 acpi: nfit: Add support for detect platform CPU cache flush on power loss
In ACPI 6.2a the platform capability structure has been added to the NFIT
tables. That provides software the ability to determine whether a system
supports the auto flushing of CPU caches on power loss. If the capability
is supported, we do not need to do dax_flush(). Plumbing the path to set the
property on per region from the NFIT tables.

This patch depends on the ACPI NFIT 6.2a platform capabilities support code
in include/acpi/actbl1.h.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
2018-02-01 15:01:15 -07:00
Dave Jiang aa9ad44a42 libnvdimm: move poison list functions to a new 'badrange' file
nfit_test needs to use the poison list manipulation code as well. Make
it more generic and in the process rename poison to badrange, and move
all the related helpers to a new file.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
[vishal: Add badrange.o to nfit_test's Kbuild]
[vishal: add a missed include in bus.c for the new badrange functions]
[vishal: rename all instances of 'be' to 'bre']
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-11-02 10:42:30 -07:00
Robin Murphy 5deb67f77a libnvdimm, nd_blk: remove mmio_flush_range()
mmio_flush_range() suffers from a lack of clearly-defined semantics,
and is somewhat ambiguous to port to other architectures where the
scope of the writeback implied by "flush" and ordering might matter,
but MMIO would tend to imply non-cacheable anyway. Per the rationale
in 67a3e8fe90 ("nd_blk: change aperture mapping from WC to WB"), the
only existing use is actually to invalidate clean cache lines for
ARCH_MEMREMAP_PMEM type mappings *without* writeback. Since the recent
cleanup of the pmem API, that also now happens to be the exact purpose
of arch_invalidate_pmem(), which would be a far more well-defined tool
for the job.

Rather than risk potentially inconsistent implementations of
mmio_flush_range() for the sake of one callsite, streamline things by
removing it entirely and instead move the ARCH_MEMREMAP_PMEM related
definitions up to the libnvdimm level, so they can be shared by NFIT
as well. This allows NFIT to be enabled for arm64.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31 15:05:10 -07:00
Dan Williams 401c0a19c6 nfit, libnvdimm, region: export 'position' in mapping info
It is useful to be able to know the position of a DIMM in an
interleave-set. Consider the case where the order of the DIMMs changes
causing a namespace to be invalidated because the interleave-set cookie no
longer matches. If the before and after state of each DIMM position is
known this state debugged by the system owner.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-04 17:20:16 -07:00
Dan Williams 9d92573fff Merge branch 'for-4.13/dax' into libnvdimm-for-next 2017-07-03 16:54:58 -07:00
Jerry Hoemann 7db5bb33ad libnvdimm, acpi, nfit: Add bus level dsm mask for pass thru.
Add a bus level dsm_mask to nvdimm_bus_descriptor to allow the passthru
calling mechanism to specify a different mask from the cmd_mask.

Populate bus_dsm_mask and use it to filter dsm calls that user can
make through the pass thru interface.

Signed-off-by: Jerry Hoemann <jerry.hoemann@hpe.com>
[djbw: use command number constants instead of a magic mask value]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-07-01 08:49:59 -07:00
Dan Williams 0b277961f4 libnvdimm, pmem: disable dax flushing when pmem is fronting a volatile region
The pmem driver attaches to both persistent and volatile memory ranges
advertised by the ACPI NFIT. When the region is volatile it is redundant
to spend cycles flushing caches at fsync(). Check if the hosting region
is volatile and do not set dax_write_cache() if it is.

Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-29 09:29:50 -07:00
Dan Williams ca6a4657e5 x86, libnvdimm, pmem: remove global pmem api
Now that all callers of the pmem api have been converted to dax helpers that
call back to the pmem driver, we can remove include/linux/pmem.h and
asm/pmem.h.

Cc: <x86@kernel.org>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Oliver O'Halloran <oohall@gmail.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-27 16:29:54 -07:00
Dan Williams faec6f8a1c libnvdimm, label: populate the type_guid property for v1.2 namespaces
The type_guid refers to the "Address Range Type GUID" for the region
backing a namespace as defined the ACPI NFIT (NVDIMM Firmware Interface
Table). This 'type' identifier specifies an access mechanism for the
given namespace. This capability replaces the confusing usage of the
'NSLABEL_FLAG_LOCAL' flag to indicate a block-aperture-mode namespace.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-15 14:31:40 -07:00
Dan Williams c12c48ce86 libnvdimm, label: add v1.2 interleave-set-cookie algorithm
The interleave-set-cookie algorithm is extended to incorporate all the
same components that are used to generate an nvdimm unique-id. For
backwards compatibility we still maintain the old v1.1 definition.

Reported-by: Nicholas Moulin <nicholas.w.moulin@intel.com>
Reported-by: Kaushik Kanetkar <kaushik.a.kanetkar@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-15 14:31:39 -07:00
Dan Williams 8f078b38dd libnvdimm: convert NDD_ flags to use bitops, introduce NDD_LOCKED
This is a preparation patch for handling locked nvdimm label regions, a
new concept as introduced by the latest DSM document on pmem.io [1]. A
future patch will leverage nvdimm_set_locked() at DIMM probe time to
flag regions that can not be enabled. There should be no functional
difference resulting from this change.

[1]: http://pmem.io/documents/NVDIMM_DSM_Interface_Example-V1.3.pdf

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-04 14:01:24 -07:00
Dan Williams 23f4984483 libnvdimm: rework region badblocks clearing
Toshi noticed that the new support for a region-level badblocks missed
the case where errors are cleared due to BTT I/O.

An initial attempt to fix this ran into a "sleeping while atomic"
warning due to taking the nvdimm_bus_lock() in the BTT I/O path to
satisfy the locking requirements of __nvdimm_bus_badblocks_clear().
However, that lock is not needed since we are not acting on any data that
is subject to change under that lock. The badblocks instance has its own
internal lock to handle mutations of the error list.

So, in order to make it clear that we are just acting on region devices,
rename __nvdimm_bus_badblocks_clear() to nvdimm_clear_badblocks_regions().
Eliminate the lock and consolidate all support routines for the new
nvdimm_account_cleared_poison() in drivers/nvdimm/bus.c. Finally, to the
opportunity to cleanup to some unnecessary casts, make the calling
convention of nvdimm_clear_badblocks_regions() clearer by replacing struct
resource with the minimal struct clear_badblocks_context, and use the
DEVICE_ATTR macro.

Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-29 15:24:03 -07:00
Dave Jiang b3b454f694 libnvdimm: fix clear poison locking with spinlock and GFP_NOWAIT allocation
The following warning results from holding a lane spinlock,
preempt_disable(), or the btt map spinlock and then trying to take the
reconfig_mutex to walk the poison list and potentially add new entries.

BUG: sleeping function called from invalid context at kernel/locking/mutex.
c:747
in_atomic(): 1, irqs_disabled(): 0, pid: 17159, name: dd
[..]
Call Trace:
dump_stack+0x85/0xc8
___might_sleep+0x184/0x250
__might_sleep+0x4a/0x90
__mutex_lock+0x58/0x9b0
? nvdimm_bus_lock+0x21/0x30 [libnvdimm]
? __nvdimm_bus_badblocks_clear+0x2f/0x60 [libnvdimm]
? acpi_nfit_forget_poison+0x79/0x80 [nfit]
? _raw_spin_unlock+0x27/0x40
mutex_lock_nested+0x1b/0x20
nvdimm_bus_lock+0x21/0x30 [libnvdimm]
nvdimm_forget_poison+0x25/0x50 [libnvdimm]
nvdimm_clear_poison+0x106/0x140 [libnvdimm]
nsio_rw_bytes+0x164/0x270 [libnvdimm]
btt_write_pg+0x1de/0x3e0 [nd_btt]
? blk_queue_enter+0x30/0x290
btt_make_request+0x11a/0x310 [nd_btt]
? blk_queue_enter+0xb7/0x290
? blk_queue_enter+0x30/0x290
generic_make_request+0x118/0x3b0

A spinlock is introduced to protect the poison list. This allows us to not
having to acquire the reconfig_mutex for touching the poison list. The
add_poison() function has been broken out into two helper functions. One to
allocate the poison entry and the other to apppend the entry. This allows us
to unlock the poison_lock in non-I/O path and continue to be able to allocate
the poison entry with GFP_KERNEL. We will use GFP_NOWAIT in the I/O path in
order to satisfy being in atomic context.

Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-13 14:23:51 -07:00
Dave Jiang 006358b35c libnvdimm: add support for clear poison list and badblocks for device dax
Providing mechanism to clear poison list via the ndctl ND_CMD_CLEAR_ERROR
call. We will update the poison list and also the badblocks at region level
if the region is in dax mode or in pmem mode and not active. In other
words we force badblocks to be cleared through write requests if the
address is currently accessed through a block device, otherwise it can
only be done via the ioctl+dsm path.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-12 21:56:43 -07:00
Dan Williams 86ef58a4e3 nfit, libnvdimm: fix interleave set cookie calculation
The interleave-set cookie is a sum that sanity checks the composition of
an interleave set has not changed from when the namespace was initially
created.  The checksum is calculated by sorting the DIMMs by their
location in the interleave-set. The comparison for the sort must be
64-bit wide, not byte-by-byte as performed by memcmp() in the broken
case.

Fix the implementation to accept correct cookie values in addition to
the Linux "memcmp" order cookies, but only allow correct cookies to be
generated going forward. It does mean that namespaces created by
third-party-tooling, or created by newer kernels with this fix, will not
validate on older kernels. However, there are a couple mitigating
conditions:

    1/ platforms with namespace-label capable NVDIMMs are not widely
       available.

    2/ interleave-sets with a single-dimm are by definition not affected
       (nothing to sort). This covers the QEMU-KVM NVDIMM emulation case.

The cookie stored in the namespace label will be fixed by any write the
namespace label, the most straightforward way to achieve this is to
write to the "alt_name" attribute of a namespace in sysfs.

Cc: <stable@vger.kernel.org>
Fixes: eaf961536e ("libnvdimm, nfit: add interleave-set state-tracking infrastructure")
Reported-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com>
Tested-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-03-01 00:49:42 -08:00
Dan Williams efda1b5d87 acpi, nfit, libnvdimm: fix / harden ars_status output length handling
Given ambiguities in the ACPI 6.1 definition of the "Output (Size)"
field of the ARS (Address Range Scrub) Status command, a firmware
implementation may in practice return 0, 4, or 8 to indicate that there
is no output payload to process.

The specification states "Size of Output Buffer in bytes, including this
field.". However, 'Output Buffer' is also the name of the entire
payload, and earlier in the specification it states "Max Query ARS
Status Output Buffer Size: Maximum size of buffer (including the Status
and Extended Status fields)".

Without this fix if the BIOS happens to return 0 it causes memory
corruption as evidenced by this result from the acpi_nfit_ctl() unit
test.

 ars_status00000000: 00020000 00000000                    ........
 BUG: stack guard page was hit at ffffc90001750000 (stack is ffffc9000174c000..ffffc9000174ffff)
 kernel stack overflow (page fault): 0000 [#1] SMP DEBUG_PAGEALLOC
 task: ffff8803332d2ec0 task.stack: ffffc9000174c000
 RIP: 0010:[<ffffffff814cfe72>]  [<ffffffff814cfe72>] __memcpy+0x12/0x20
 RSP: 0018:ffffc9000174f9a8  EFLAGS: 00010246
 RAX: ffffc9000174fab8 RBX: 0000000000000000 RCX: 000000001fffff56
 RDX: 0000000000000000 RSI: ffff8803231f5a08 RDI: ffffc90001750000
 RBP: ffffc9000174fa88 R08: ffffc9000174fab0 R09: ffff8803231f54b8
 R10: 0000000000000008 R11: 0000000000000001 R12: 0000000000000000
 R13: 0000000000000000 R14: 0000000000000003 R15: ffff8803231f54a0
 FS:  00007f3a611af640(0000) GS:ffff88033ed00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: ffffc90001750000 CR3: 0000000325b20000 CR4: 00000000000406e0
 Stack:
  ffffffffa00bc60d 0000000000000008 ffffc90000000001 ffffc9000174faac
  0000000000000292 ffffffffa00c24e4 ffffffffa00c2914 0000000000000000
  0000000000000000 ffffffff00000003 ffff880331ae8ad0 0000000800000246
 Call Trace:
  [<ffffffffa00bc60d>] ? acpi_nfit_ctl+0x49d/0x750 [nfit]
  [<ffffffffa01f4fe0>] nfit_test_probe+0x670/0xb1b [nfit_test]

Cc: <stable@vger.kernel.org>
Fixes: 747ffe11b4 ("libnvdimm, tools/testing/nvdimm: fix 'ars_status' output buffer sizing")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-12-06 16:08:10 -08:00