In case kmemdup fails, the fix releases resources and returns to
avoid the NULL pointer dereference.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In case kmemdup fails, the fix goes to blk_err to avoid NULL
pointer dereference.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* 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
* Fix nfit-bus command submission regression
* 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.
* Enhance dax_device alignment checks
* Add support for the Hyper-V family of device-specific-methods (DSMs)
* Add several fixes and workarounds for Hyper-V compatibility.
* Fix support to cache the dirty-shutdown-count at init.
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Merge tag 'libnvdimm-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"The bulk of this has been in -next since before the merge window
opened, with no known collisions / issues reported.
The only detail worth noting, outside the summary below, is that the
"libnvdimm-start-pad" topic has been truncated to just cleanups and
small fixes. The full topic branch would have doubled down on hacks
around the "section alignment" limitation of the core-mm, instead
effort is now being spent to address that root issue in the memory
hotplug implementation for v5.2.
- Fix nfit-bus command submission regression
- 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
- Enhance dax_device alignment checks
- Add support for the Hyper-V family of device-specific-methods
(DSMs)
- Add several fixes and workarounds for Hyper-V compatibility
- Fix support to cache the dirty-shutdown-count at init"
* tag 'libnvdimm-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (25 commits)
libnvdimm/namespace: Clean up holder_class_store()
libnvdimm/of_pmem: Fix platform_no_drv_owner.cocci warnings
acpi/nfit: Update NFIT flags error message
libnvdimm/btt: Fix LBA masking during 'free list' population
libnvdimm/btt: Remove unnecessary code in btt_freelist_init
libnvdimm/pfn: Remove dax_label_reserve
dax: Check the end of the block-device capacity with dax_direct_access()
nfit/ars: Avoid stale ARS results
nfit/ars: Allow root to busy-poll the ARS state machine
nfit/ars: Introduce scrub_flags
nfit/ars: Remove ars_start_flags
nfit/ars: Attempt short-ARS even in the no_init_ars case
nfit/ars: Attempt a short-ARS whenever the ARS state is idle at boot
acpi/nfit: Require opt-in for read-only label configurations
libnvdimm/pmem: Honor force_raw for legacy pmem regions
libnvdimm/pfn: Account for PAGE_SIZE > info-block-size in nd_pfn_init()
libnvdimm: Fix altmap reservation size calculation
libnvdimm, pfn: Fix over-trim in trim_pfn_device()
acpi/nfit: Fix bus command validation
libnvdimm/dimm: Add a no-BLK quirk based on NVDIMM family
...
Merge the initial lead-in cleanups and fixes that resulted from the
effort to resolve bugs in the section-alignment padding implementation
in the nvdimm core. The back half of this topic is abandoned in favor of
implementing sub-section hotplug support.
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.
Use sysfs_streq() in place of open-coded strcmp()'s that check for an
optional "\n" at the end of the input.
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Remove .owner field if calls are used which set it automatically
Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The Linux BTT implementation assumes that log entries will never have
the 'zero' flag set, and indeed it never sets that flag for log entries
itself.
However, the UEFI spec is ambiguous on the exact format of the LBA field
of a log entry, specifically as to whether it should include the
additional flag bits or not. While a zero bit doesn't make sense in the
context of a log entry, other BTT implementations might still have it set.
If an implementation does happen to have it set, we would happily read
it in as the next block to write to for writes. Since a high bit is set,
it pushes the block number out of the range of an 'arena', and we fail
such a write with an EIO.
Follow the robustness principle, and tolerate such implementations by
stripping out the zero flag when populating the free list during
initialization. Additionally, use the same stripped out entries for
detection of incomplete writes and map restoration that happens at this
stage.
Add a sysfs file 'log_zero_flags' that indicates the ability to accept
such a layout to userspace applications. This enables 'ndctl
check-namespace' to recognize whether the kernel is able to handle zero
flags, or whether it should attempt a fix-up under the --repair option.
Cc: Dan Williams <dan.j.williams@intel.com>
Reported-by: Dexuan Cui <decui@microsoft.com>
Reported-by: Pedro d'Aquino Filocre F S Barbuda <pbarbuda@microsoft.com>
Tested-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
We call btt_log_read() twice, once to get the 'old' log entry, and again
to get the 'new' entry. However, we have no use for the 'old' entry, so
remove it.
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The reserve was for an abandoned effort to add label (partitioning
support) to device-dax instances. Remove it.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
For recovery, where non-dax access is needed to a given physical address
range, and testing, allow the 'force_raw' attribute to override the
default establishment of a dev_pagemap.
Otherwise without this capability it is possible to end up with a
namespace that can not be activated due to corrupted info-block, and one
that can not be repaired due to a section collision.
Cc: <stable@vger.kernel.org>
Fixes: 004f1afbe1 ("libnvdimm, pmem: direct map legacy pmem by default")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Similar to "libnvdimm: Fix altmap reservation size calculation" provide
for a reservation of a full page worth of info block space at info-block
establishment time. Typically there is already slack in the padding
from honoring the default 2MB alignment, but provide for a reservation
for corner case configurations that would otherwise fit.
Cc: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Libnvdimm reserves the first 8K of pfn and devicedax namespaces to
store a superblock describing the namespace. This 8K reservation
is contained within the altmap area which the kernel uses for the
vmemmap backing for the pages within the namespace. The altmap
allows for some pages at the start of the altmap area to be reserved
and that mechanism is used to protect the superblock from being
re-used as vmemmap backing.
The number of PFNs to reserve is calculated using:
PHYS_PFN(SZ_8K)
Which is implemented as:
#define PHYS_PFN(x) ((unsigned long)((x) >> PAGE_SHIFT))
So on systems where PAGE_SIZE is greater than 8K the reservation
size is truncated to zero and the superblock area is re-used as
vmemmap backing. As a result all the namespace information stored
in the superblock (i.e. if it's a PFN or DAX namespace) is lost
and the namespace needs to be re-created to get access to the
contents.
This patch fixes this by using PFN_UP() rather than PHYS_PFN() to ensure
that at least one page is reserved. On systems with a 4K pages size this
patch should have no effect.
Cc: stable@vger.kernel.org
Cc: Dan Williams <dan.j.williams@intel.com>
Fixes: ac515c084b ("libnvdimm, pmem, pfn: move pfn setup to the core")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
When trying to see whether current nd_region intersects with others,
trim_pfn_device() has already calculated the *size* to be expanded to
SECTION size.
Do not double append 'adjust' to 'size' when calculating whether the end
of a region collides with the next pmem region.
Fixes: ae86cbfef3 "libnvdimm, pfn: Pad pfn namespaces relative to other regions"
Cc: <stable@vger.kernel.org>
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
Force the device registration for nvdimm devices to be closer to the actual
device. This is achieved by using either the NUMA node ID of the region, or
of the parent. By doing this we can have everything above the region based
on the region, and everything below the region based on the nvdimm bus.
By guaranteeing NUMA locality I see an improvement of as high as 25% for
per-node init of a system with 12TB of persistent memory.
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
The input parameter should be enum nvdimm_passphrase_type instead of bool
for selection of master/user for selection of extended master passphrase
state or the regular user passphrase state.
Fixes: 89fa9d8ea7 ("...add Intel DSM 1.8 master passphrase support")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The UEFI 2.7 specification sets expectations that the 'updating' flag is
eventually cleared. To date, the libnvdimm core has never adhered to
that protocol. The policy of the core matches the policy of other
multi-device info-block formats like MD-Software-RAID that expect
administrator intervention on inconsistent info-blocks, not automatic
invalidation.
However, some pre-boot environments may unfortunately attempt to "clean
up" the labels and invalidate a set when it fails to find at least one
"non-updating" label in the set. Clear the updating flag after set
updates to minimize the window of vulnerability to aggressive pre-boot
environments.
Ideally implementations would not write to the label area outside of
creating namespaces.
Note that this only minimizes the window, it does not close it as the
system can still crash while clearing the flag and the set can be
subsequently deleted / invalidated by the pre-boot environment.
Fixes: f524bf271a ("libnvdimm: write pmem label set")
Cc: <stable@vger.kernel.org>
Cc: Kelly Couch <kelly.j.couch@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
Merge misc updates from Andrew Morton:
- large KASAN update to use arm's "software tag-based mode"
- a few misc things
- sh updates
- ocfs2 updates
- just about all of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (167 commits)
kernel/fork.c: mark 'stack_vm_area' with __maybe_unused
memcg, oom: notify on oom killer invocation from the charge path
mm, swap: fix swapoff with KSM pages
include/linux/gfp.h: fix typo
mm/hmm: fix memremap.h, move dev_page_fault_t callback to hmm
hugetlbfs: Use i_mmap_rwsem to fix page fault/truncate race
hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization
memory_hotplug: add missing newlines to debugging output
mm: remove __hugepage_set_anon_rmap()
include/linux/vmstat.h: remove unused page state adjustment macro
mm/page_alloc.c: allow error injection
mm: migrate: drop unused argument of migrate_page_move_mapping()
blkdev: avoid migration stalls for blkdev pages
mm: migrate: provide buffer_migrate_page_norefs()
mm: migrate: move migrate_page_lock_buffers()
mm: migrate: lock buffers before migrate_page_move_mapping()
mm: migration: factor out code to compute expected number of page references
mm, page_alloc: enable pcpu_drain with zone capability
kmemleak: add config to select auto scan
mm/page_alloc.c: don't call kasan_free_pages() at deferred mem init
...
* Add support for the security features of nvdimm devices that
implement a security model similar to ATA hard drive security. The
security model supports locking access to the media at
device-power-loss, to be unlocked with a passphrase, and secure-erase
(crypto-scramble).
Unlike the ATA security case where the kernel expects device
security to be managed in a pre-OS environment, the libnvdimm security
implementation allows key provisioning and key-operations at OS
runtime. Keys are managed with the kernel's encrypted-keys facility to
provide data-at-rest security for the libnvdimm key material. The
usage model mirrors fscrypt key management, but is driven via
libnvdimm sysfs.
* Miscellaneous updates for api usage and comment fixes.
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Merge tag 'libnvdimm-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"The vast bulk of this update is the new support for the security
capabilities of some nvdimms.
The userspace tooling for this capability is still a work in progress,
but the changes survive the existing libnvdimm unit tests. The changes
also pass manual checkout on hardware and the new nfit_test emulation
of the security capability.
The touches of the security/keys/ files have received the necessary
acks from Mimi and David. Those changes were necessary to allow for a
new generic encrypted-key type, and allow the nvdimm sub-system to
lookup key material referenced by the libnvdimm-sysfs interface.
Summary:
- Add support for the security features of nvdimm devices that
implement a security model similar to ATA hard drive security. The
security model supports locking access to the media at
device-power-loss, to be unlocked with a passphrase, and
secure-erase (crypto-scramble).
Unlike the ATA security case where the kernel expects device
security to be managed in a pre-OS environment, the libnvdimm
security implementation allows key provisioning and key-operations
at OS runtime. Keys are managed with the kernel's encrypted-keys
facility to provide data-at-rest security for the libnvdimm key
material. The usage model mirrors fscrypt key management, but is
driven via libnvdimm sysfs.
- Miscellaneous updates for api usage and comment fixes"
* tag 'libnvdimm-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (21 commits)
libnvdimm/security: Quiet security operations
libnvdimm/security: Add documentation for nvdimm security support
tools/testing/nvdimm: add Intel DSM 1.8 support for nfit_test
tools/testing/nvdimm: Add overwrite support for nfit_test
tools/testing/nvdimm: Add test support for Intel nvdimm security DSMs
acpi/nfit, libnvdimm/security: add Intel DSM 1.8 master passphrase support
acpi/nfit, libnvdimm/security: Add security DSM overwrite support
acpi/nfit, libnvdimm: Add support for issue secure erase DSM to Intel nvdimm
acpi/nfit, libnvdimm: Add enable/update passphrase support for Intel nvdimms
acpi/nfit, libnvdimm: Add disable passphrase support to Intel nvdimm.
acpi/nfit, libnvdimm: Add unlock of nvdimm support for Intel DIMMs
acpi/nfit, libnvdimm: Add freeze security support to Intel nvdimm
acpi/nfit, libnvdimm: Introduce nvdimm_security_ops
keys-encrypted: add nvdimm key format type to encrypted keys
keys: Export lookup_user_key to external users
acpi/nfit, libnvdimm: Store dimm id as a member to struct nvdimm
libnvdimm, namespace: Replace kmemdup() with kstrndup()
libnvdimm, label: Switch to bitmap_zalloc()
ACPI/nfit: Adjust annotation for why return 0 if fail to find NFIT at start
libnvdimm, bus: Check id immediately following ida_simple_get
...
The last step before devm_memremap_pages() returns success is to allocate
a release action, devm_memremap_pages_release(), to tear the entire setup
down. However, the result from devm_add_action() is not checked.
Checking the error from devm_add_action() is not enough. The api
currently relies on the fact that the percpu_ref it is using is killed by
the time the devm_memremap_pages_release() is run. Rather than continue
this awkward situation, offload the responsibility of killing the
percpu_ref to devm_memremap_pages_release() directly. This allows
devm_memremap_pages() to do the right thing relative to init failures and
shutdown.
Without this change we could fail to register the teardown of
devm_memremap_pages(). The likelihood of hitting this failure is tiny as
small memory allocations almost always succeed. However, the impact of
the failure is large given any future reconfiguration, or disable/enable,
of an nvdimm namespace will fail forever as subsequent calls to
devm_memremap_pages() will fail to setup the pgmap_radix since there will
be stale entries for the physical address range.
An argument could be made to require that the ->kill() operation be set in
the @pgmap arg rather than passed in separately. However, it helps code
readability, tracking the lifetime of a given instance, to be able to grep
the kill routine directly at the devm_memremap_pages() call site.
Link: http://lkml.kernel.org/r/154275558526.76910.7535251937849268605.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Fixes: e8d5134833 ("memremap: change devm_memremap_pages interface...")
Reviewed-by: "Jérôme Glisse" <jglisse@redhat.com>
Reported-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 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.
The security implementation is too chatty. For example, the common case
is that security is not enabled / setup, and booting a qemu
configuration currently yields:
nvdimm nmem0: request_key() found no key
nvdimm nmem0: failed to unlock dimm: -126
nvdimm nmem1: request_key() found no key
nvdimm nmem1: failed to unlock dimm: -126
Convert all security related log messages to debug level.
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Add nfit_test support for DSM functions "Get Security State",
"Set Passphrase", "Disable Passphrase", "Unlock Unit", "Freeze Lock",
and "Secure Erase" for the fake DIMMs.
Also adding a sysfs knob in order to put the DIMMs in "locked" state. The
order of testing DIMM unlocking would be.
1a. Disable DIMM X.
1b. Set Passphrase to DIMM X.
2. Write to
/sys/devices/platform/nfit_test.0/nfit_test_dimm/test_dimmX/lock_dimm
3. Renable DIMM X
4. Check DIMM X state via sysfs "security" attribute for nmemX.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
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>
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>
Add support for enabling and updating passphrase on the Intel nvdimms.
The passphrase is the an encrypted key in the kernel user keyring.
We trigger the update via writing "update <old_keyid> <new_keyid>" to the
sysfs attribute "security". If no <old_keyid> exists (for enabling
security) then a 0 should be used.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
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>
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>
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>
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>
kstrndup() takes care of '\0' terminator for the strings.
Use it here instead of kmemdup() + explicit terminating the input string.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Switch to bitmap_zalloc() to show clearly what we are allocating.
Besides that it returns pointer of bitmap type instead of opaque void *.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The id check was not executed immediately following ida_simple_get. Just
change the codes position, without function change.
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>
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Merge tag 'v4.20-rc6' into for-4.21/block
Pull in v4.20-rc6 to resolve the conflict in NVMe, but also to get the
two corruption fixes. We're going to be overhauling the direct dispatch
path, and we need to do that on top of the changes we made for that
in mainline.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit cfe30b8720 "libnvdimm, pmem: adjust for section collisions with
'System RAM'" enabled Linux to workaround occasions where platform
firmware arranges for "System RAM" and "Persistent Memory" to collide
within a single section boundary. Unfortunately, as reported in this
issue [1], platform firmware can inflict the same collision between
persistent memory regions.
The approach of interrogating iomem_resource does not work in this
case because platform firmware may merge multiple regions into a single
iomem_resource range. Instead provide a method to interrogate regions
that share the same parent bus.
This is a stop-gap until the core-MM can grow support for hotplug on
sub-section boundaries.
[1]: https://github.com/pmem/ndctl/issues/76
Fixes: cfe30b8720 ("libnvdimm, pmem: adjust for section collisions with...")
Cc: <stable@vger.kernel.org>
Reported-by: Patrick Geary <patrickg@supermicro.com>
Tested-by: Patrick Geary <patrickg@supermicro.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
With the legacy request path gone there is no real need to override the
queue_lock.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
* Improve the efficiency and performance of reading nvdimm-namespace
labels. Reduce the amount of label data read at driver load time by a
few orders of magnitude. Reduce heavyweight call-outs to
platform-firmware routines.
* Handle media errors located in the 'struct page' array stored on a
persistent memory namespace. Let the kernel clear these errors rather
than an awkward userspace workaround.
* Fix Address Range Scrub (ARS) completion tracking. Correct occasions
where the kernel indicates completion of ARS before submission.
* Fix asynchronous device registration reference counting.
* Add support for reporting an nvdimm dirty-shutdown-count via sysfs.
* Fix various small libnvdimm core and uapi issues.
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Merge tag 'libnvdimm-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
- Improve the efficiency and performance of reading nvdimm-namespace
labels. Reduce the amount of label data read at driver load time by a
few orders of magnitude. Reduce heavyweight call-outs to
platform-firmware routines.
- Handle media errors located in the 'struct page' array stored on a
persistent memory namespace. Let the kernel clear these errors rather
than an awkward userspace workaround.
- Fix Address Range Scrub (ARS) completion tracking. Correct occasions
where the kernel indicates completion of ARS before submission.
- Fix asynchronous device registration reference counting.
- Add support for reporting an nvdimm dirty-shutdown-count via sysfs.
- Fix various small libnvdimm core and uapi issues.
* tag 'libnvdimm-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (21 commits)
acpi, nfit: Further restrict userspace ARS start requests
acpi, nfit: Fix Address Range Scrub completion tracking
UAPI: ndctl: Remove use of PAGE_SIZE
UAPI: ndctl: Fix g++-unsupported initialisation in headers
tools/testing/nvdimm: Populate dirty shutdown data
acpi, nfit: Collect shutdown status
acpi, nfit: Introduce nfit_mem flags
libnvdimm, label: Fix sparse warning
nvdimm: Use namespace index data to reduce number of label reads needed
nvdimm: Split label init out from the logic for getting config data
nvdimm: Remove empty if statement
nvdimm: Clarify comment in sizeof_namespace_index
nvdimm: Sanity check labeloff
libnvdimm, dimm: Maximize label transfer size
libnvdimm, pmem: Fix badblocks population for 'raw' namespaces
libnvdimm, namespace: Drop the repeat assignment for variable dev->parent
libnvdimm, region: Fail badblocks listing for inactive regions
libnvdimm, pfn: during init, clear errors in the metadata area
libnvdimm: Set device node in nd_device_register
libnvdimm: Hold reference on parent while scheduling async init
...
The kbuild robot reports:
drivers/nvdimm/label.c:500:32: warning: restricted __le32 degrades to integer
...read 'nslot' into a local u32.
Reported-by: kbuild test robot <lkp@intel.com>
Acked-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patch adds logic that is meant to make use of the namespace index data
to reduce the number of reads that are needed to initialize a given
namespace. The general idea is that once we have enough data to validate
the namespace index we do so and then proceed to fetch only those labels
that are not listed as being "free". By doing this I am seeing a total time
reduction from about 4-5 seconds to 2-3 seconds for 24 NVDIMM modules each
with 128K of label config area.
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patch splits the initialization of the label data into two functions.
One for doing the init, and another for reading the actual configuration
data. The idea behind this is that by doing this we create a symmetry
between the getting and setting of config data in that we have a function
for both. In addition it will make it easier for us to identify the bits
that are related to init versus the pieces that are a wrapper for reading
data from the ACPI interface.
So for example by splitting things out like this it becomes much more
obvious that we were performing checks that weren't necessarily related to
the set/get operations such as relying on ndd->data being present when the
set and get ops should not care about a locally cached copy of the label
area.
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patch removes an empty statement from an if expression and promotes
the else statement to the if expression with the expression logic reversed.
I feel this is more readable as the empty statement can lead to issues if
any additional logic was ever added.
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
When working on the label code I found it rather confusing to see several
spots that reference a minimum label size of 256 while working with labels
that are 128 bytes in size.
This patch is meant to provide a clarification on one of the comments that
was at the heart of the issue. Specifically for version 1.2 and later of
the namespace specification the minimum label size is 256, prior to that
the minimum label size was 128. So we should state that as such to avoid
confusion.
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
