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* ACPI: NFIT: Fix flexible_array.cocci warningsDan Williams2021-01-111-47/+28
| | | | | | | | | | | | | | | | | | | | Julia and 0day report: Zero-length and one-element arrays are deprecated, see Documentation/process/deprecated.rst Flexible-array members should be used instead. However, a straight conversion to flexible arrays yields: drivers/acpi/nfit/core.c:2276:4: error: flexible array member in a struct with no named members drivers/acpi/nfit/core.c:2287:4: error: flexible array member in a struct with no named members Instead, just use plain arrays not embedded flexible arrays. Cc: Denis Efremov <efremov@linux.com> Reported-by: kernel test robot <lkp@intel.com> Reported-by: Julia Lawall <julia.lawall@inria.fr> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* ACPI: NFIT: Fix input validation of bus-familyDan Williams2020-11-231-1/+5
| | | | | | | | | | | | | | | | | Dan reports that smatch thinks userspace can craft an out-of-bound bus family number. However, nd_cmd_clear_to_send() blocks all non-zero values of bus-family since only the kernel can initiate these commands. However, in the speculation path, family is a user controlled array index value so mask it for speculation safety. Also, since the nd_cmd_clear_to_send() safety is non-obvious and possibly may change in the future include input validation as if userspace could get past the nd_cmd_clear_to_send() gatekeeper. Link: http://lore.kernel.org/r/20201111113000.GA1237157@mwanda Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Fixes: 6450ddbd5d8e ("ACPI: NFIT: Define runtime firmware activation commands") Cc: <stable@vger.kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* ACPI/nfit: avoid accessing uninitialized memory in acpi_nfit_ctl()Zhen Lei2020-11-181-4/+5
| | | | | | | | | | | The ACPI_ALLOCATE() does not zero the "buf", so when the condition "integer->type != ACPI_TYPE_INTEGER" in int_to_buf() is met, the result is unpredictable in acpi_nfit_ctl(). Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/20201118073517.1884-1-thunder.leizhen@huawei.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* ACPI: Fix whitespace inconsistenciesMaximilian Luz2020-11-091-5/+5
| | | | | | | | Replaces spaces with tabs where spaces have been (inconsistently) used for indentation and removes trailing whitespaces. Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI: NFIT: Fix comparison to '-ENXIO'Zhang Qilong2020-10-271-1/+1
| | | | | | | | | | | Initial value of rc is '-ENXIO', and we should use the initial value to check it. Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Reviewed-by: Vishal Verma <vishal.l.verma@intel.com> [ rjw: Subject edit ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge branch 'acpi-numa'Rafael J. Wysocki2020-10-131-4/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * acpi-numa: docs: mm: numaperf.rst Add brief description for access class 1. node: Add access1 class to represent CPU to memory characteristics ACPI: HMAT: Fix handling of changes from ACPI 6.2 to ACPI 6.3 ACPI: Let ACPI know we support Generic Initiator Affinity Structures x86: Support Generic Initiator only proximity domains ACPI: Support Generic Initiator only domains ACPI / NUMA: Add stub function for pxm_to_node() irq-chip/gic-v3-its: Fix crash if ITS is in a proximity domain without processor or memory ACPI: Remove side effect of partly creating a node in acpi_get_node() ACPI: Rename acpi_map_pxm_to_online_node() to pxm_to_online_node() ACPI: Remove side effect of partly creating a node in acpi_map_pxm_to_online_node() ACPI: Do not create new NUMA domains from ACPI static tables that are not SRAT ACPI: Add out of bounds and numa_off protections to pxm_to_node()
| * ACPI: Rename acpi_map_pxm_to_online_node() to pxm_to_online_node()Jonathan Cameron2020-09-241-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | As this function is no longer allowed to create new mappings let us rename it to reflect this. Note all nodes should already exist before any of the users of this function are called. Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| * ACPI: Do not create new NUMA domains from ACPI static tables that are not SRATJonathan Cameron2020-09-241-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Several ACPI static tables contain references to proximity domains. ACPI 6.3 has clarified that only entries in SRAT may define a new domain (sec 5.2.16). Those tables described in the ACPI spec have additional clarifying text. NFIT: Table 5-132, "Integer that represents the proximity domain to which the memory belongs. This number must match with corresponding entry in the SRAT table." HMAT: Table 5-145, "... This number must match with the corresponding entry in the SRAT table's processor affinity structure ... if the initiator is a processor, or the Generic Initiator Affinity Structure if the initiator is a generic initiator". IORT and DMAR are defined by external specifications. Intel Virtualization Technology for Directed I/O Rev 3.1 does not make any explicit statements, but the general SRAT statement above will still apply. https://software.intel.com/sites/default/files/managed/c5/15/vt-directed-io-spec.pdf IO Remapping Table, Platform Design Document rev D, also makes not explicit statement, but refers to ACPI SRAT table for more information and again the generic SRAT statement above applies. https://developer.arm.com/documentation/den0049/d/ In conclusion, any proximity domain specified in these tables, should be a reference to a proximity domain also found in SRAT, and they should not be able to instantiate a new domain. Hence we switch to pxm_to_node() which will only return existing nodes. Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Barry Song <song.bao.hua@hisilicon.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | ACPI: NFIT: Use kobj_to_dev() insteadWang Qing2020-09-151-2/+2
|/ | | | | | | | | Use kobj_to_dev() instead of container_of() Signed-off-by: Wang Qing <wangqing@vivo.com> Acked-by: Vishal Verma <vishal.l.verma@intel.com> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge tag 'libnvdimm-for-5.9' of ↵Linus Torvalds2020-08-114-42/+600
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updayes from Vishal Verma: "You'd normally receive this pull request from Dan Williams, but he's busy watching a newborn (Congrats Dan!), so I'm watching libnvdimm this cycle. This adds a new feature in libnvdimm - 'Runtime Firmware Activation', and a few small cleanups and fixes in libnvdimm and DAX. I'd originally intended to make separate topic-based pull requests - one for libnvdimm, and one for DAX, but some of the DAX material fell out since it wasn't quite ready. Summary: - add 'Runtime Firmware Activation' support for NVDIMMs that advertise the relevant capability - misc libnvdimm and DAX cleanups" * tag 'libnvdimm-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: libnvdimm/security: ensure sysfs poll thread woke up and fetch updated attr libnvdimm/security: the 'security' attr never show 'overwrite' state libnvdimm/security: fix a typo ACPI: NFIT: Fix ARS zero-sized allocation dax: Fix incorrect argument passed to xas_set_err() ACPI: NFIT: Add runtime firmware activate support PM, libnvdimm: Add runtime firmware activation support libnvdimm: Convert to DEVICE_ATTR_ADMIN_RO() drivers/dax: Expand lock scope to cover the use of addresses fs/dax: Remove unused size parameter dax: print error message by pr_info() in __generic_fsdax_supported() driver-core: Introduce DEVICE_ATTR_ADMIN_{RO,RW} tools/testing/nvdimm: Emulate firmware activation commands tools/testing/nvdimm: Prepare nfit_ctl_test() for ND_CMD_CALL emulation tools/testing/nvdimm: Add command debug messages tools/testing/nvdimm: Cleanup dimm index passing ACPI: NFIT: Define runtime firmware activation commands ACPI: NFIT: Move bus_dsm_mask out of generic nvdimm_bus_descriptor libnvdimm: Validate command family indices
| * ACPI: NFIT: Fix ARS zero-sized allocationDan Williams2020-08-031-3/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pending commit in -next "devres: handle zero size in devm_kmalloc()" triggers a boot regression due to the ARS implementation expecting NULL from a zero-sized allocation. Avoid the zero-sized allocation by skipping ARS, otherwise crashes with the following signature when de-referencing ZERO_SIZE_PTR. BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page RIP: 0010:__acpi_nfit_scrub+0x28a/0x350 [nfit] [..] Call Trace: ? acpi_nfit_query_poison+0x6a/0x180 [nfit] acpi_nfit_scrub+0x36/0xb0 [nfit] process_one_work+0x23c/0x580 worker_thread+0x50/0x3b0 Otherwise the implementation correctly aborts when NULL is returned from devm_kzalloc() in ars_status_alloc(). Link: https://lore.kernel.org/r/159624590643.3037264.14157533719042907758.stgit@dwillia2-desk3.amr.corp.intel.com Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
| * ACPI: NFIT: Add runtime firmware activate supportDan Williams2020-07-284-4/+436
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Plumb the platform specific backend for the generic libnvdimm firmware activate interface. Register dimm level operations to arm/disarm activation, and register bus level operations to report the dynamic platform-quiesce time relative to the number of dimms armed for firmware activation. A new nfit-specific bus attribute "firmware_activate_noidle" is added to allow the activation to switch between platform enforced, and OS opportunistic device quiesce. In other words, let the hibernate cycle handle in-flight device-dma rather than the platform attempting to increase PCI-E timeouts and the like. Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
| * tools/testing/nvdimm: Emulate firmware activation commandsDan Williams2020-07-251-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Augment the existing firmware update emulation to track activations and validate proper update vs activate sequencing. The DIMM firmware activate capability has a concept of a maximum amount of time platform firmware will quiesce the system relative to how many DIMMs are being activated in parallel. Simulate that DIMM activation happens serially, 1 second per-DIMM, and limit the max at 3 seconds. The nfit_test0 bus emulates 5 DIMMs so it will take 2 activations to update all DIMMs. Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Reported-by: Andy Shevchenko <andriy.shevchenko@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
| * ACPI: NFIT: Define runtime firmware activation commandsDan Williams2020-07-253-29/+135
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Platform reboots are expensive. Towards reducing downtime to apply firmware updates the Intel NVDIMM command definition is growing support for applying live firmware updates that only require temporarily suspending memory traffic instead of a full reboot. Follow-on commits add support for triggering firmware activation, this patch only defines the commands, adds probe support, and validates that they are blocked via the ioctl path. The ioctl-path block ensures that the OS is in charge since these commands have side effects only the OS can handle. Specifically firmware activation may cause the memory controller to be quiesced on the order of 100s of milliseconds. In that case Linux ensure the activation only takes place while the OS is in a suspend state. Link: https://pmem.io/documents/IntelOptanePMem_DSM_Interface-V2.0.pdf Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
| * ACPI: NFIT: Move bus_dsm_mask out of generic nvdimm_bus_descriptorDan Williams2020-07-252-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DSMs are strictly an ACPI mechanism, evict the bus_dsm_mask concept from the generic 'struct nvdimm_bus_descriptor' object. As a side effect the test facility ->bus_nfit_cmd_force_en is no longer necessary. The test infrastructure can communicate that information directly in ->bus_dsm_mask. Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
| * libnvdimm: Validate command family indicesDan Williams2020-07-252-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ND_CMD_CALL format allows for a general passthrough of passlisted commands targeting a given command set. However there is no validation of the family index relative to what the bus supports. - Update the NFIT bus implementation (the only one that supports ND_CMD_CALL passthrough) to also passlist the valid set of command family indices. - Update the generic __nd_ioctl() path to validate that field on behalf of all implementations. Fixes: 31eca76ba2fc ("nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism") Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
* | ACPI: Replace HTTP links with HTTPS onesAlexander A. Klimov2020-07-271-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Acked-by: Vishal Verma <vishal.l.verma@intel.com> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge tag 'libnvdimm-for-5.8' of ↵Linus Torvalds2020-06-131-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: "Small collection of cleanups to rework usage of ->queuedata and the GUID api" * tag 'libnvdimm-for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: nvdimm/pmem: stop using ->queuedata nvdimm/btt: stop using ->queuedata nvdimm/blk: stop using ->queuedata libnvdimm: Replace guid_copy() with import_guid() where it makes sense
| * libnvdimm: Replace guid_copy() with import_guid() where it makes senseAndy Shevchenko2020-04-221-1/+1
| | | | | | | | | | | | | | | | | | | | There is a specific API to treat raw data as GUID, i.e. import_guid(). Use it instead of guid_copy() with explicit casting. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/20200422130539.45636-1-andriy.shevchenko@linux.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | x86/mce: Fix all mce notifiers to update the mce->kflags bitmaskTony Luck2020-04-141-0/+1
|/ | | | | | | | | | | | | | If the handler took any action to log or deal with the error, set a bit in mce->kflags so that the default handler on the end of the machine check chain can see what has been done. Get rid of NOTIFY_STOP returns. Make the EDAC and dev-mcelog handlers skip over errors already processed by CEC. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20200214222720.13168-5-tony.luck@intel.com
* Merge branch 'for-5.7/libnvdimm' into libnvdimm-for-nextDan Williams2020-04-021-6/+6
|\ | | | | | | | | | | | | | | | | | | | | | | - Introduce 'zero_page_range' as a dax operation. This facilitates filesystem-dax operation without a block-device. - Advertise a persistence-domain for of_pmem and papr_scm. The persistence domain indicates where cpu-store cycles need to reach in the platform-memory subsystem before the platform will consider them power-fail protected. - Fixup some flexible-array declarations.
| * ACPI: NFIT: Replace zero-length array with flexible-array memberGustavo A. R. Silva2020-03-251-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: https://lore.kernel.org/r/20200319195046.GA452@embeddedor.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | Merge branch 'for-5.6/libnvdimm-fixes' into libnvdimm-for-nextDan Williams2020-04-022-4/+7
|\ \ | | | | | | | | | | | | | | | Pick up some miscellaneous minor fixes, that missed v5.6-final, including a some smatch reports in the ioctl path and some unit test compilation fixups.
| * | acpi/nfit: improve bounds checking for 'func'Dan Carpenter2020-02-282-4/+7
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 'func' variable can come from the user in the __nd_ioctl(). If it's too high then the (1 << func) shift in acpi_nfit_clear_to_send() is undefined. In acpi_nfit_ctl() we pass 'func' to test_bit(func, &dsm_mask) which could result in an out of bounds access. To fix these issues, I introduced the NVDIMM_CMD_MAX (31) define and updated nfit_dsm_revid() to use that define as well instead of magic numbers. Fixes: 11189c1089da ("acpi/nfit: Fix command-supported detection") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/20200225161927.hvftuq7kjn547fyj@kili.mountain Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* / libnvdimm/region: Introduce NDD_LABELINGDan Williams2020-03-171-1/+3
|/ | | | | | | | | | | | | | | | | | | | | The NDD_ALIASING flag is used to indicate where pmem capacity might alias with blk capacity and require labeling. It is also used to indicate whether the DIMM supports labeling. Separate this latter capability into its own flag so that the NDD_ALIASING flag is scoped to true aliased configurations. To my knowledge aliased configurations only exist in the ACPI spec, there are no known platforms that ship this support in production. This clarity allows namespace-capacity alignment constraints around interleave-ways to be relaxed. Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Link: https://lore.kernel.org/r/158041477856.3889308.4212605617834097674.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* libnvdimm: Move nvdimm_bus_attribute_group to device_typeDan Williams2019-11-191-1/+0
| | | | | | | | | | | | | | | A 'struct device_type' instance can carry default attributes for the device. Use this facility to remove the export of nvdimm_bus_attribute_group and put the responsibility on the core rather than leaf implementations to define this attribute. Cc: Ira Weiny <ira.weiny@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Link: https://lore.kernel.org/r/157309903815.1582359.6418211876315050283.stgit@dwillia2-desk3.amr.corp.intel.com
* libnvdimm: Move nvdimm_attribute_group to device_typeDan Williams2019-11-191-1/+0
| | | | | | | | | | | | | | | A 'struct device_type' instance can carry default attributes for the device. Use this facility to remove the export of nvdimm_attribute_group and put the responsibility on the core rather than leaf implementations to define this attribute. Cc: Ira Weiny <ira.weiny@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Link: https://lore.kernel.org/r/157309903201.1582359.10966209746585062329.stgit@dwillia2-desk3.amr.corp.intel.com
* libnvdimm: Move nd_mapping_attribute_group to device_typeDan Williams2019-11-191-1/+0
| | | | | | | | | | | | | | | A 'struct device_type' instance can carry default attributes for the device. Use this facility to remove the export of nd_mapping_attribute_group and put the responsibility on the core rather than leaf implementations to define this attribute. Cc: Ira Weiny <ira.weiny@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Link: https://lore.kernel.org/r/157309902686.1582359.6749533709859492704.stgit@dwillia2-desk3.amr.corp.intel.com
* libnvdimm: Move nd_region_attribute_group to device_typeDan Williams2019-11-191-1/+0
| | | | | | | | | | | | | | | A 'struct device_type' instance can carry default attributes for the device. Use this facility to remove the export of nd_region_attribute_group and put the responsibility on the core rather than leaf implementations to define this attribute. Cc: Ira Weiny <ira.weiny@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Link: https://lore.kernel.org/r/157309902169.1582359.16828508538444551337.stgit@dwillia2-desk3.amr.corp.intel.com
* libnvdimm: Move nd_numa_attribute_group to device_typeDan Williams2019-11-191-1/+0
| | | | | | | | | | | | | | | A 'struct device_type' instance can carry default attributes for the device. Use this facility to remove the export of nd_numa_attribute_group and put the responsibility on the core rather than leaf implementations to define this attribute. Cc: Ira Weiny <ira.weiny@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Link: https://lore.kernel.org/r/157401269537.43284.14411189404186877352.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* libnvdimm: Move nd_device_attribute_group to device_typeDan Williams2019-11-171-2/+0
| | | | | | | | | | | | | | | | | | A 'struct device_type' instance can carry default attributes for the device. Use this facility to remove the export of nd_device_attribute_group and put the responsibility on the core rather than leaf implementations to define this attribute. For regions this creates a new nd_region_attribute_groups[] added to the per-region device-type instances. Cc: Ira Weiny <ira.weiny@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Link: https://lore.kernel.org/r/157309901138.1582359.12909354140826530394.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* ACPI: NFIT: Fix unlock on error in scrub_show()Dan Carpenter2019-10-221-1/+1
| | | | | | | | | | | | We change the locking in this function and forgot to update this error path so we are accidentally still holding the "dev->lockdep_mutex". Fixes: 87a30e1f05d7 ("driver-core, libnvdimm: Let device subsystems add local lockdep coverage") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Cc: 5.3+ <stable@vger.kernel.org> # 5.3+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* libnvdimm/security: Introduce a 'frozen' attributeDan Williams2019-08-291-27/+32
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Merge tag 'libnvdimm-fixes-5.3-rc2' of ↵Linus Torvalds2019-07-272-14/+38
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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()
| * driver-core, libnvdimm: Let device subsystems add local lockdep coverageDan Williams2019-07-182-14/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* | libnvdimm: nd_region flush callback supportPankaj Gupta2019-07-051-2/+2
|/ | | | | | | | | | | | 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>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295Thomas Gleixner2019-06-053-27/+3
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner2019-05-211-0/+1
| | | | | | | | | | | | | | 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>
* libnvdimm/security, acpi/nfit: unify zero-key for all security commandsDave Jiang2019-03-301-6/+4
| | | | | | | | | | | 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>
* acpi/nfit: Always dump _DSM output payloadDan Williams2019-03-221-6/+6
| | | | | | | | | | 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: 31eca76ba2fc9 ("...whitelisted dimm command marshaling mechanism") Reported-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* Merge tag 'devdax-for-5.1' of ↵Linus Torvalds2019-03-161-2/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * acpi/nfit, device-dax: Identify differentiated memory with a unique numa-nodeDan Williams2019-01-061-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 branch 'for-5.1/nfit/ars' into libnvdimm-for-nextDan Williams2019-03-112-24/+57
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
| * | nfit/ars: Avoid stale ARS resultsDan Williams2019-02-202-1/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: 0caeef63e6d2 ("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>
| * | nfit/ars: Allow root to busy-poll the ARS state machineDan Williams2019-02-202-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: bc6ba8085842 ("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>
| * | nfit/ars: Introduce scrub_flagsDan Williams2019-02-202-15/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | nfit/ars: Remove ars_start_flagsDan Williams2019-02-202-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | nfit/ars: Attempt short-ARS even in the no_init_ars caseDan Williams2019-02-201-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The no_init_ars option is meant to prevent long-ARS, but short-ARS should be allowed to grab any immediate results. Fixes: bc6ba8085842 ("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>
| * | nfit/ars: Attempt a short-ARS whenever the ARS state is idle at bootDan Williams2019-02-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If query-ARS reports that ARS has stopped and requires continuation attempt to retrieve short-ARS results before continuing the long operation. Fixes: bc6ba8085842 ("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>
* | | Merge branch 'for-5.1/libnvdimm' into libnvdimm-for-nextDan Williams2019-03-112-28/+71
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.