* 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
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.
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>
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>
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>
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>
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 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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Before we add more libnvdimm-private fields to nd_mapping make it clear
which parameters are input vs libnvdimm internals. Use struct
nd_mapping_desc instead of struct nd_mapping in nd_region_desc and make
struct nd_mapping private to libnvdimm.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
nvdimm_clear_poison cleared the user-visible badblocks, and sent
commands to the NVDIMM to clear the areas marked as 'poison', but it
neglected to clear the same areas from the internal poison_list which is
used to marshal ARS results before sorting them by namespace. As a
result, once on-demand ARS functionality was added:
37b137f nfit, libnvdimm: allow an ARS scrub to be triggered on demand
A scrub triggered from either sysfs or an MCE was found to be adding
stale entries that had been cleared from gendisk->badblocks, but were
still present in nvdimm_bus->poison_list. Additionally, the stale entries
could be triggered into producing stale disk->badblocks by simply disabling
and re-enabling the namespace or region.
This adds the missing step of clearing poison_list entries when clearing
poison, so that it is always in sync with badblocks.
Fixes: 37b137f ("nfit, libnvdimm: allow an ARS scrub to be triggered on demand")
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Per "ACPI 6.1 Section 9.20.3" NVDIMM devices, children of the ACPI0012
NVDIMM Root device, can receive health event notifications.
Given that these devices are precluded from registering a notification
handler via acpi_driver.acpi_device_ops (due to no _HID), we use
acpi_install_notify_handler() directly. The registered handler,
acpi_nvdimm_notify(), triggers a poll(2) event on the nmemX/nfit/flags
sysfs attribute when a health event notification is received.
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Normally, an ARS (Address Range Scrub) only happens at
boot/initialization time. There can however arise situations where a
bus-wide rescan is needed - notably, in the case of discovering a latent
media error, we should do a full rescan to figure out what other sectors
are bad, and thus potentially avoid triggering an mce on them in the
future. Also provide a sysfs trigger to start a bus-wide scrub.
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Let the provider module be explicitly passed in rather than implicitly
assumed by the module that calls nvdimm_bus_register(). This is in
preparation for unifying the nfit and nfit_test driver teardown paths.
Reviewed-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
nvdimm_flush() is a replacement for the x86 'pcommit' instruction. It is
an optional write flushing mechanism that an nvdimm bus can provide for
the pmem driver to consume. In the case of the NFIT nvdimm-bus-provider
nvdimm_flush() is implemented as a series of flush-hint-address [1]
writes to each dimm in the interleave set (region) that backs the
namespace.
The nvdimm_has_flush() routine relies on platform firmware to describe
the flushing capabilities of a platform. It uses the heuristic of
whether an nvdimm bus provider provides flush address data to return a
ternary result:
1: flush addresses defined
0: dimm topology described without flush addresses (assume ADR)
-errno: no topology information, unable to determine flush mechanism
The pmem driver is expected to take the following actions on this ternary
result:
1: nvdimm_flush() in response to REQ_FUA / REQ_FLUSH and shutdown
0: do not set, WC or FUA on the queue, take no further action
-errno: warn and then operate as if nvdimm_has_flush() returned '0'
The caveat of this heuristic is that it can not distinguish the "dimm
does not have flush address" case from the "platform firmware is broken
and failed to describe a flush address". Given we are already
explicitly trusting the NFIT there's not much more we can do beyond
blacklisting broken firmwares if they are ever encountered.
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for triggering flushes of a DIMM's writes-posted-queue
(WPQ) via the pmem driver move mapping of flush hint addresses to the
region driver. Since this uses devm_nvdimm_memremap() the flush
addresses will remain mapped while any region to which the dimm belongs
is active.
We need to communicate more information to the nvdimm core to facilitate
this mapping, namely each dimm object now carries an array of flush hint
address resources.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that all shared mappings are handled by devm_nvdimm_memremap() we no
longer need nfit_spa_map() nor do we need to trigger a callback to the
bus provider at region disable time.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for generically mapping flush hint addresses for both the
BLK and PMEM use case, provide a generic / reference counted mapping
api. Given the fact that a dimm may belong to multiple regions (PMEM
and BLK), the flush hint addresses need to be held valid as long as any
region associated with the dimm is active. This is similar to the
existing BLK-region case where multiple BLK-regions may share an
aperture mapping. Up-level this shared / reference-counted mapping
capability from the nfit driver to a core nvdimm capability.
This eliminates the need for the nd_blk_region.disable() callback. Note
that the removal of nfit_spa_map() and related infrastructure is
deferred to a later patch.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Clarify the distinction between "commands", the ioctls userspace calls
to request the kernel take some action on a given dimm device, and
"_DSMs", the actual function numbers used in the firmware interface to
the DIMM. _DSMs are ACPI specific whereas commands are Linux kernel
generic.
This is in preparation for breaking the 1:1 implicit relationship
between the kernel ioctl number space and the firmware specific function
numbers.
Cc: Jerry Hoemann <jerry.hoemann@hpe.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
nd_ioctl() must first read in the fixed sized portion of an ioctl so
that it can then determine the size of the variable part.
Prepare for ND_CMD_CALL calls which have larger fixed portion
envelope.
Signed-off-by: Jerry Hoemann <jerry.hoemann@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
While the nfit driver is issuing address range scrub commands and
reaping the results do not permit an ars_start command issued from
userspace. The scrub thread assumes that all ars completions are for
scrubs initiated by platform firmware at boot, or by the nfit driver.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Introduce a workqueue that will be used to run address range scrub
asynchronously with the rest of nvdimm device probing.
Userspace still wants notification when probing operations complete, so
introduce a new callback to flush this workqueue when userspace is
awaiting probe completion.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The return value from an 'ndctl_fn' reports the command execution
status, i.e. was the command properly formatted and was it successfully
submitted to the bus provider. The new 'cmd_rc' parameter allows the bus
provider to communicate command specific results, translated into
common error codes.
Convert the ARS commands to this scheme to:
1/ Consolidate status reporting
2/ Prepare for for expanding ars unit test cases
3/ Make the implementation more generic
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The original format of these commands from the "NVDIMM DSM Interface
Example" [1] are superseded by the ACPI 6.1 definition of the "NVDIMM Root
Device _DSMs" [2].
[1]: http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf
[2]: http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf
"9.20.7 NVDIMM Root Device _DSMs"
Changes include:
1/ New 'restart' fields in ars_status, unfortunately these are
implemented in the middle of the existing definition so this change
is not backwards compatible. The expectation is that shipping
platforms will only ever support the ACPI 6.1 definition.
2/ New status values for ars_start ('busy') and ars_status ('overflow').
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Linda Knippers <linda.knippers@hpe.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Use the output length specified in the command to size the receive
buffer rather than the arbitrary 4K limit.
This bug was hiding the fact that the ndctl implementation of
ndctl_bus_cmd_new_ars_status() was not specifying an output buffer size.
Cc: <stable@vger.kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
