Commit Graph

156 Commits

Author SHA1 Message Date
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
Linus Torvalds
523634db14 libnvdimm fixes v5.3-rc2
- Fix duplicate device_unregister() calls (multiple threads competing to
   do unregister work when scheduling device removal from a sysfs attribute
   of the self-same device).
 
 - Fix badblocks registration order bug. Ensure region badblocks are
   initialized in advance of namespace registration.
 
 - Fix a deadlock between the bus lock and probe operations.
 
 - Export device-core infrastructure to coordinate async operations via
   the device ->dead state.
 
 - Add device-core infrastructure to validate device_lock() usage with
   lockdep.
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Merge tag 'libnvdimm-fixes-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm fixes from Dan Williams:
 "A collection of locking and async operations fixes for v5.3-rc2. These
  had been soaking in a branch targeting the merge window, but missed
  due to a regression hunt. This fixed up version has otherwise been in
  -next this past week with no reported issues.

  In order to gain confidence in the locking changes the pull also
  includes a debug / instrumentation patch to enable lockdep coverage
  for libnvdimm subsystem operations that depend on the device_lock for
  exclusion. As mentioned in the changelog it is a hack, but it works
  and documents the locking expectations of the sub-system in a way that
  others can use lockdep to verify. The driver core touches got an ack
  from Greg.

  Summary:

   - Fix duplicate device_unregister() calls (multiple threads competing
     to do unregister work when scheduling device removal from a sysfs
     attribute of the self-same device).

   - Fix badblocks registration order bug. Ensure region badblocks are
     initialized in advance of namespace registration.

   - Fix a deadlock between the bus lock and probe operations.

   - Export device-core infrastructure to coordinate async operations
     via the device ->dead state.

   - Add device-core infrastructure to validate device_lock() usage with
     lockdep"

* tag 'libnvdimm-fixes-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  driver-core, libnvdimm: Let device subsystems add local lockdep coverage
  libnvdimm/bus: Fix wait_nvdimm_bus_probe_idle() ABBA deadlock
  libnvdimm/bus: Stop holding nvdimm_bus_list_mutex over __nd_ioctl()
  libnvdimm/bus: Prepare the nd_ioctl() path to be re-entrant
  libnvdimm/region: Register badblocks before namespaces
  libnvdimm/bus: Prevent duplicate device_unregister() calls
  drivers/base: Introduce kill_device()
2019-07-27 08:25:51 -07:00
Dan Williams
87a30e1f05 driver-core, libnvdimm: Let device subsystems add local lockdep coverage
For good reason, the standard device_lock() is marked
lockdep_set_novalidate_class() because there is simply no sane way to
describe the myriad ways the device_lock() ordered with other locks.
However, that leaves subsystems that know their own local device_lock()
ordering rules to find lock ordering mistakes manually. Instead,
introduce an optional / additional lockdep-enabled lock that a subsystem
can acquire in all the same paths that the device_lock() is acquired.

A conversion of the NFIT driver and NVDIMM subsystem to a
lockdep-validate device_lock() scheme is included. The
debug_nvdimm_lock() implementation implements the correct lock-class and
stacking order for the libnvdimm device topology hierarchy.

Yes, this is a hack, but hopefully it is a useful hack for other
subsystems device_lock() debug sessions. Quoting Greg:

    "Yeah, it feels a bit hacky but it's really up to a subsystem to mess up
     using it as much as anything else, so user beware :)

     I don't object to it if it makes things easier for you to debug."

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/156341210661.292348.7014034644265455704.stgit@dwillia2-desk3.amr.corp.intel.com
2019-07-18 16:23:27 -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
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Dave Jiang
d2e5b6436c libnvdimm/security, acpi/nfit: unify zero-key for all security commands
With zero-key defined, we can remove previous detection of key id 0 or null
key in order to deal with a zero-key situation. Syncing all security
commands to use the zero-key. Helper functions are introduced to return the
data that points to the actual key payload or the zero_key. This helps
uniformly handle the key material even with zero_key.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-03-30 08:27:07 -07:00
Dan Williams
351f339faa acpi/nfit: Always dump _DSM output payload
The dynamic-debug statements for command payload output only get emitted
when the command is not ND_CMD_CALL. Move the output payload dumping
ahead of the early return path for ND_CMD_CALL.

Fixes: 31eca76ba2 ("...whitelisted dimm command marshaling mechanism")
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-03-22 16:19:18 -07:00
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
4083014e32 Merge branch 'for-5.1/nfit/ars' into libnvdimm-for-next
Merge several updates to the ARS implementation. Highlights include:

* Support retrieval of short-ARS results if the ARS state is "requires
  continuation", and even if the "no_init_ars" module parameter is
  specified.
* Allow busy-polling of the kernel ARS state by allowing root to reset
  the exponential back-off timer.
* Filter potentially stale ARS results by tracking query-ARS relative to
  the previous start-ARS.
2019-03-11 12:37:55 -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
Toshi Kani
5c9d62d002 acpi/nfit: Update NFIT flags error message
ACPI NFIT flags field reports major errors on NVDIMM, which need
user's attention.

Update the current log to a proper error message with dev_err().
The current message string is kept for grep-compatibility.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Robert Elliott <elliott@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-03-01 09:44:59 -08:00
Dan Williams
78153dd45e nfit/ars: Avoid stale ARS results
Gate ARS result consumption on whether the OS issued start-ARS since the
previous consumption. The BIOS may only clear its result buffers after a
successful start-ARS.

Fixes: 0caeef63e6 ("libnvdimm: Add a poison list and export badblocks")
Cc: <stable@vger.kernel.org>
Reported-by: Krzysztof Rusocki <krzysztof.rusocki@intel.com>
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-20 14:18:59 -08:00
Dan Williams
5479b2757f nfit/ars: Allow root to busy-poll the ARS state machine
The ARS implementation implements exponential back-off on the poll
interval to prevent high-frequency access to the DIMM / platform
interface. Depending on when the ARS completes the poll interval may
exceed the completion event by minutes. Allow root to reset the timeout
each time it probes the status. A one-second timeout is still enforced,
but root can otherwise can control the poll interval.

Fixes: bc6ba80858 ("nfit, address-range-scrub: rework and simplify ARS...")
Cc: <stable@vger.kernel.org>
Reported-by: Erwin Tsaur <erwin.tsaur@oracle.com>
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-20 14:18:59 -08:00
Dan Williams
e34b8252a3 nfit/ars: Introduce scrub_flags
In preparation for introducing new flags to gate whether ARS results are
stale, or poll the completion state, convert the existing flags to an
unsigned long with enumerated values. This conversion allows the flags
to be atomically updated outside of ->init_mutex.

Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-20 14:18:59 -08:00
Dan Williams
317a992ab9 nfit/ars: Remove ars_start_flags
The ars_start_flags property of 'struct acpi_nfit_desc' is no longer
used since ARS_REQ_SHORT and ARS_REQ_LONG were added.

Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-20 14:18:59 -08:00
Dan Williams
fa3ed4d981 nfit/ars: Attempt short-ARS even in the no_init_ars case
The no_init_ars option is meant to prevent long-ARS, but short-ARS
should be allowed to grab any immediate results.

Fixes: bc6ba80858 ("nfit, address-range-scrub: rework and simplify ARS...")
Cc: <stable@vger.kernel.org>
Reported-by: Erwin Tsaur <erwin.tsaur@oracle.com>
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-20 14:18:59 -08:00
Dan Williams
c6c5df293b nfit/ars: Attempt a short-ARS whenever the ARS state is idle at boot
If query-ARS reports that ARS has stopped and requires continuation
attempt to retrieve short-ARS results before continuing the long
operation.

Fixes: bc6ba80858 ("nfit, address-range-scrub: rework and simplify ARS...")
Cc: <stable@vger.kernel.org>
Reported-by: Krzysztof Rusocki <krzysztof.rusocki@intel.com>
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-13 08:58:40 -08:00
Dan Williams
0171b6b781 acpi/nfit: Require opt-in for read-only label configurations
Recent fixes to command handling enabled Linux to read label
configurations that it could not before. Unfortunately that means that
configurations that were operating in label-less mode will be broken as
the kernel ignores the existing namespace configuration and tries to
honor the new found labels.

Fortunately this seems limited to a case where Linux can quirk the
behavior and maintain the existing label-less semantics by default.
When the platform does not emit an _LSW method, disable all label access
methods. Provide a 'force_labels' module parameter to allow read-only
label operation.

Fixes: 11189c1089 ("acpi/nfit: Fix command-supported detection")
Reported-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-12 20:14:15 -08:00
Dan Williams
ebe9f6f19d acpi/nfit: Fix bus command validation
Commit 11189c1089 "acpi/nfit: Fix command-supported detection" broke
ND_CMD_CALL for bus-level commands. The "func = cmd" assumption is only
valid for:

    ND_CMD_ARS_CAP
    ND_CMD_ARS_START
    ND_CMD_ARS_STATUS
    ND_CMD_CLEAR_ERROR

The function number otherwise needs to be pulled from the command
payload for:

    NFIT_CMD_TRANSLATE_SPA
    NFIT_CMD_ARS_INJECT_SET
    NFIT_CMD_ARS_INJECT_CLEAR
    NFIT_CMD_ARS_INJECT_GET

Update cmd_to_func() for the bus case and call it in the common path.

Fixes: 11189c1089 ("acpi/nfit: Fix command-supported detection")
Cc: <stable@vger.kernel.org>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: Grzegorz Burzynski <grzegorz.burzynski@intel.com>
Tested-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-02-07 14:56:50 -08:00
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
Dexuan Cui
1194c41331 nfit: Add Hyper-V NVDIMM DSM command set to white list
Add the Hyper-V _DSM command set to the white list of NVDIMM command
sets.

This command set is documented at http://www.uefi.org/RFIC_LIST
(see "Virtual NVDIMM 0x1901").

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-29 22:09:31 -08:00
Dexuan Cui
43f89877f2 nfit: acpi_nfit_ctl(): Check out_obj->type in the right place
In the case of ND_CMD_CALL, we should also check out_obj->type.

The patch uses out_obj->type, which is a short alias to
out_obj->package.type.

Fixes: 31eca76ba2 ("nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism")
Cc: <stable@vger.kernel.org>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-29 22:08:34 -08:00
Dan Williams
f596c8844f nfit: Fix nfit_intel_shutdown_status() command submission
The implementation is broken in all the ways the unit test did not touch:

1/ The local definition of in_buf and in_obj violated C99 initializer
   expectations for zeroing. By only initializing 2 out of the three
   struct members the compiler was free to zero-initialize the remaining
   entry even though the aliased location in the union was initialized.

2/ The implementation made assumptions about the state of the 'smart'
   payload after command execution that are satisfied by
   acpi_nfit_ctl(), but not acpi_evaluate_dsm().

3/ populate_shutdown_status() is skipped on Intel NVDIMMs due to the early
   return for skipping the common _LS{I,R,W} enabling.

4/ The input length should be zero.

This breakage was missed due to the unit test implementation only
testing the case where nfit_intel_shutdown_status() returns a valid
payload.

Much of this complexity would be saved if acpi_nfit_ctl() could be used, but
that currently requires a 'struct nvdimm *' argument and one is not created
until later in the init process. The health result is needed before the device
is created because the payload gates whether the nmemX/nfit/dirty_shutdown
property is visible in sysfs.

Cc: <stable@vger.kernel.org>
Fixes: 0ead11181f ("acpi, nfit: Collect shutdown status")
Reported-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-29 22:08:34 -08:00
Dan Williams
11189c1089 acpi/nfit: Fix command-supported detection
The _DSM function number validation only happens to succeed when the
generic Linux command number translation corresponds with a
DSM-family-specific function number. This breaks NVDIMM-N
implementations that correctly implement _LSR, _LSW, and _LSI, but do
not happen to publish support for DSM function numbers 4, 5, and 6.

Recall that the support for _LS{I,R,W} family of methods results in the
DIMM being marked as supporting those command numbers at
acpi_nfit_register_dimms() time. The DSM function mask is only used for
ND_CMD_CALL support of non-NVDIMM_FAMILY_INTEL devices.

Fixes: 31eca76ba2 ("nfit, libnvdimm: limited/whitelisted dimm command...")
Cc: <stable@vger.kernel.org>
Link: https://github.com/pmem/ndctl/issues/78
Reported-by: Sujith Pandel <sujith_pandel@dell.com>
Tested-by: Sujith Pandel <sujith_pandel@dell.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-21 09:58:31 -08:00
Dan Williams
5e9e38d0db acpi/nfit: Block function zero DSMs
In preparation for using function number 0 as an error value, prevent it
from being considered a valid function value by acpi_nfit_ctl().

Cc: <stable@vger.kernel.org>
Cc: stuart hayes <stuart.w.hayes@gmail.com>
Fixes: e02fb7264d ("nfit: add Microsoft NVDIMM DSM command set...")
Reported-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-21 09:58:29 -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
Wei Yang
b4fe30e45a acpi/nfit: Remove duplicate set nd_set in acpi_nfit_init_interleave_set()
We allocate nd_set in acpi_nfit_init_interleave_set() and assignn it to
ndr_desc, while the assignment is done twice in this function.

This patch removes the first assignment. No functional change.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-14 18:59:08 -08:00
Tony Luck
0919871ac3 acpi/nfit: Fix race accessing memdev in nfit_get_smbios_id()
Possible race accessing memdev structures after dropping the
mutex. Dan Williams says this could race against another thread
that is doing:

 # echo "ACPI0012:00" > /sys/bus/acpi/drivers/nfit/unbind

Reported-by: Jane Chu <jane.chu@oracle.com>
Fixes: 23222f8f8d ("acpi, nfit: Add function to look up nvdimm...")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-11 14:50:29 -08:00
Nathan Chancellor
ccb7f15a8a nfit: Mark some functions as __maybe_unused
On arm64 little endian allyesconfig:

drivers/acpi/nfit/intel.c:149:12: warning: unused function 'intel_security_unlock' [-Wunused-function]
static int intel_security_unlock(struct nvdimm *nvdimm,
           ^
drivers/acpi/nfit/intel.c:230:12: warning: unused function 'intel_security_erase' [-Wunused-function]
static int intel_security_erase(struct nvdimm *nvdimm,
           ^
drivers/acpi/nfit/intel.c:279:12: warning: unused function 'intel_security_query_overwrite' [-Wunused-function]
static int intel_security_query_overwrite(struct nvdimm *nvdimm)
           ^
drivers/acpi/nfit/intel.c:316:12: warning: unused function 'intel_security_overwrite' [-Wunused-function]
static int intel_security_overwrite(struct nvdimm *nvdimm,
           ^
4 warnings generated.

Mark these functions as __maybe_unused because they are only used when
CONFIG_X86 is set.

Fixes: 4c6926a23b ("acpi/nfit, libnvdimm: Add unlock of nvdimm support for Intel DIMMs")
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-08 22:04:38 -08:00
Xiaochun Lee
8a7f02f67c ACPI/nfit: delete the function to_acpi_nfit_desc
The function to_acpi_nfit_desc and function to_acpi_desc
do the same things,delete the function to_acpi_nfit_desc,
and keep the inline function to_acpi_desc.

Signed-off-by: Xiaochun Lee <lixc17@lenovo.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-08 17:28:46 -08:00
Xiaochun Lee
dadbcb450c ACPI/nfit: delete the redundant header file
The header file "intel.h" is repeated here, So delete one.

Signed-off-by: Xiaochun Lee <lixc17@lenovo.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-01-08 17:28:45 -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
Dan Williams
4b5f747e82 Merge miscellaneous libnvdimm updates for 4.21
* Use common helpers, bitmap_zalloc() and kstrndup(), to replace open
  coded versions.
* Clarify the comments around hotplug vs initial init case for the nfit
  driver.
* Cleanup the libnvdimm init path.
2018-12-27 19:54:10 -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
Ocean He
9f619d4769 ACPI/nfit: Adjust annotation for why return 0 if fail to find NFIT at start
Add detailed explanation for why it's ok to return 0 if we fail to find
an NFIT at startup. Refer to chapter 9.20.2 NVDIMM Root Device in ACPI
6.2 spec.

Signed-off-by: Ocean He <hehy1@lenovo.com>
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>
2018-12-10 15:41:50 -08:00
Dan Williams
b5fd2e00a6 acpi/nfit: Fix user-initiated ARS to be "ARS-long" rather than "ARS-short"
A "short" ARS (address range scrub) instructs the platform firmware to
return known errors. In contrast, a "long" ARS instructs platform
firmware to arrange every data address on the DIMM to be read / checked
for poisoned data.

The conversion of the flags in commit d3abaf43ba "acpi, nfit: Fix
Address Range Scrub completion tracking", changed the meaning of passing
'0' to acpi_nfit_ars_rescan(). Previously '0' meant "not short", now '0'
is ARS_REQ_SHORT. Pass ARS_REQ_LONG to restore the expected scrub-type
behavior of user-initiated ARS sessions.

Fixes: d3abaf43ba ("acpi, nfit: Fix Address Range Scrub completion tracking")
Reported-by: Jacek Zloch <jacek.zloch@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-05 14:16:13 -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
Linus Torvalds
25e19c1fe4 libnvdimm 4.20-rc3
- Address Range Scrub overflow continuation handling has been broken
   since it was initially merged. It was only recently that error injection
   and platform-BIOS support enabled this corner case to be exercised.
 
 - The recent attempt to provide more isolation for the kernel Address
   Range Scrub state machine from userapace initiated sessions triggers a
   lockdep report. Revert and try again at the next merge window.
 
 - Fix a kasan reported buffer overflow in libnvdimm unit test
   infrastrucutre (nfit_test)
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Merge tag 'libnvdimm-fixes-4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm fixes from Dan Williams:
 "A small batch of fixes for v4.20-rc3.

  The overflow continuation fix addresses something that has been broken
  for several releases. Arguably it could wait even longer, but it's a
  one line fix and this finishes the last of the known address range
  scrub bug reports. The revert addresses a lockdep regression. The unit
  tests are not critical to fix, but no reason to hold this fix back.

  Summary:

   - Address Range Scrub overflow continuation handling has been broken
     since it was initially merged. It was only recently that error
     injection and platform-BIOS support enabled this corner case to be
     exercised.

   - The recent attempt to provide more isolation for the kernel Address
     Range Scrub state machine from userapace initiated sessions
     triggers a lockdep report. Revert and try again at the next merge
     window.

   - Fix a kasan reported buffer overflow in libnvdimm unit test
     infrastrucutre (nfit_test)"

* tag 'libnvdimm-fixes-4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  Revert "acpi, nfit: Further restrict userspace ARS start requests"
  acpi, nfit: Fix ARS overflow continuation
  tools/testing/nvdimm: Fix the array size for dimm devices.
2018-11-18 12:21:09 -08:00
Dan Williams
2121db0963 Revert "acpi, nfit: Further restrict userspace ARS start requests"
The following lockdep splat results from acquiring the init_mutex in
acpi_nfit_clear_to_send():

 WARNING: possible circular locking dependency detected
 lt-daxdev-error/7216 is trying to acquire lock:
 00000000f694db15 (&acpi_desc->init_mutex){+.+.}, at: acpi_nfit_clear_to_send+0x27/0x80 [nfit]

 but task is already holding lock:
 00000000182298f2 (&nvdimm_bus->reconfig_mutex){+.+.}, at: __nd_ioctl+0x457/0x610 [libnvdimm]

 which lock already depends on the new lock.


 the existing dependency chain (in reverse order) is:

 -> #1 (&nvdimm_bus->reconfig_mutex){+.+.}:
        nvdimm_badblocks_populate+0x41/0x150 [libnvdimm]
        nd_region_notify+0x95/0xb0 [libnvdimm]
        nd_device_notify+0x40/0x50 [libnvdimm]
        ars_complete+0x7f/0xd0 [nfit]
        acpi_nfit_scrub+0xbb/0x410 [nfit]
        process_one_work+0x22b/0x5c0
        worker_thread+0x3c/0x390
        kthread+0x11e/0x140
        ret_from_fork+0x3a/0x50

 -> #0 (&acpi_desc->init_mutex){+.+.}:
        __mutex_lock+0x83/0x980
        acpi_nfit_clear_to_send+0x27/0x80 [nfit]
        __nd_ioctl+0x474/0x610 [libnvdimm]
        nd_ioctl+0xa4/0xb0 [libnvdimm]
        do_vfs_ioctl+0xa5/0x6e0
        ksys_ioctl+0x70/0x80
        __x64_sys_ioctl+0x16/0x20
        do_syscall_64+0x60/0x210
        entry_SYSCALL_64_after_hwframe+0x49/0xbe

New infrastructure is needed to be able to perform this check without
acquiring the lock.

Fixes: 594861215c ("acpi, nfit: Further restrict userspace ARS start")
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-11-10 09:54:28 -08:00
Dan Williams
3fa58dcab5 acpi, nfit: Fix ARS overflow continuation
When the platform BIOS is unable to report all the media error records
it requires the OS to restart the scrub at a prescribed location. The
driver detects the overflow condition, but then fails to report it to
the ARS state machine after reaping the records. Propagate -ENOSPC
correctly to continue the ARS operation.

Cc: <stable@vger.kernel.org>
Fixes: 1cf03c00e7 ("nfit: scrub and register regions in a workqueue")
Reported-by: Jacek Zloch <jacek.zloch@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-11-10 09:54:28 -08:00
Vishal Verma
e8a308e5f4 acpi/nfit, x86/mce: Validate a MCE's address before using it
The NFIT machine check handler uses the physical address from the mce
structure, and compares it against information in the ACPI NFIT table
to determine whether that location lies on an NVDIMM. The mce->addr
field however may not always be valid, and this is indicated by the
MCI_STATUS_ADDRV bit in the status field.

Export mce_usable_address() which already performs validation for the
address, and use it in the NFIT handler.

Fixes: 6839a6d96f ("nfit: do an ARS scrub on hitting a latent media error")
Reported-by: Robert Elliott <elliott@hpe.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Williams <dan.j.williams@intel.com>
CC: Dave Jiang <dave.jiang@intel.com>
CC: elliott@hpe.com
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: Len Brown <lenb@kernel.org>
CC: linux-acpi@vger.kernel.org
CC: linux-edac <linux-edac@vger.kernel.org>
CC: linux-nvdimm@lists.01.org
CC: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
CC: "Rafael J. Wysocki" <rjw@rjwysocki.net>
CC: Ross Zwisler <zwisler@kernel.org>
CC: stable <stable@vger.kernel.org>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Tony Luck <tony.luck@intel.com>
CC: x86-ml <x86@kernel.org>
CC: Yazen Ghannam <yazen.ghannam@amd.com>
Link: http://lkml.kernel.org/r/20181026003729.8420-2-vishal.l.verma@intel.com
2018-11-06 19:13:26 +01:00
Vishal Verma
5d96c9342c acpi/nfit, x86/mce: Handle only uncorrectable machine checks
The MCE handler for nfit devices is called for memory errors on a
Non-Volatile DIMM and adds the error location to a 'badblocks' list.
This list is used by the various NVDIMM drivers to avoid consuming known
poison locations during IO.

The MCE handler gets called for both corrected and uncorrectable errors.
Until now, both kinds of errors have been added to the badblocks list.
However, corrected memory errors indicate that the problem has already
been fixed by hardware, and the resulting interrupt is merely a
notification to Linux.

As far as future accesses to that location are concerned, it is
perfectly fine to use, and thus doesn't need to be included in the above
badblocks list.

Add a check in the nfit MCE handler to filter out corrected mce events,
and only process uncorrectable errors.

Fixes: 6839a6d96f ("nfit: do an ARS scrub on hitting a latent media error")
Reported-by: Omar Avelar <omar.avelar@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Dan Williams <dan.j.williams@intel.com>
CC: Dave Jiang <dave.jiang@intel.com>
CC: elliott@hpe.com
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: Len Brown <lenb@kernel.org>
CC: linux-acpi@vger.kernel.org
CC: linux-edac <linux-edac@vger.kernel.org>
CC: linux-nvdimm@lists.01.org
CC: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
CC: "Rafael J. Wysocki" <rjw@rjwysocki.net>
CC: Ross Zwisler <zwisler@kernel.org>
CC: stable <stable@vger.kernel.org>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Tony Luck <tony.luck@intel.com>
CC: x86-ml <x86@kernel.org>
CC: Yazen Ghannam <yazen.ghannam@amd.com>
Link: http://lkml.kernel.org/r/20181026003729.8420-1-vishal.l.verma@intel.com
2018-11-06 19:13:10 +01:00