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12 daysdocs: ioctl-number: fix a typo in ioctl-number.rstGabriel Whigham1-1/+1
"userspace" was misspelled as "userpace". Signed-off-by: Gabriel Whigham <gabewhigham@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260130042131.51975-1-gabewhigham@gmail.com>
2025-11-27liveupdate: luo_core: Live Update OrchestratorPasha Tatashin1-0/+2
Patch series "Live Update Orchestrator", v8. This series introduces the Live Update Orchestrator, a kernel subsystem designed to facilitate live kernel updates using a kexec-based reboot. This capability is critical for cloud environments, allowing hypervisors to be updated with minimal downtime for running virtual machines. LUO achieves this by preserving the state of selected resources, such as memory, devices and their dependencies, across the kernel transition. As a key feature, this series includes support for preserving memfd file descriptors, which allows critical in-memory data, such as guest RAM or any other large memory region, to be maintained in RAM across the kexec reboot. The other series that use LUO, are VFIO [1], IOMMU [2], and PCI [3] preservations. Github repo of this series [4]. The core of LUO is a framework for managing the lifecycle of preserved resources through a userspace-driven interface. Key features include: - Session Management Userspace agent (i.e. luod [5]) creates named sessions, each represented by a file descriptor (via centralized agent that controls /dev/liveupdate). The lifecycle of all preserved resources within a session is tied to this FD, ensuring automatic kernel cleanup if the controlling userspace agent crashes or exits unexpectedly. - File Preservation A handler-based framework allows specific file types (demonstrated here with memfd) to be preserved. Handlers manage the serialization, restoration, and lifecycle of their specific file types. - File-Lifecycle-Bound State A new mechanism for managing shared global state whose lifecycle is tied to the preservation of one or more files. This is crucial for subsystems like IOMMU or HugeTLB, where multiple file descriptors may depend on a single, shared underlying resource that must be preserved only once. - KHO Integration LUO drives the Kexec Handover framework programmatically to pass its serialized metadata to the next kernel. The LUO state is finalized and added to the kexec image just before the reboot is triggered. In the future this step will also be removed once stateless KHO is merged [6]. - Userspace Interface Control is provided via ioctl commands on /dev/liveupdate for creating and retrieving sessions, as well as on session file descriptors for managing individual files. - Testing The series includes a set of selftests, including userspace API validation, kexec-based lifecycle tests for various session and file scenarios, and a new in-kernel test module to validate the FLB logic. Introduce LUO, a mechanism intended to facilitate kernel updates while keeping designated devices operational across the transition (e.g., via kexec). The primary use case is updating hypervisors with minimal disruption to running virtual machines. For userspace side of hypervisor update we have copyless migration. LUO is for updating the kernel. This initial patch lays the groundwork for the LUO subsystem. Further functionality, including the implementation of state transition logic, integration with KHO, and hooks for subsystems and file descriptors, will be added in subsequent patches. Create a character device at /dev/liveupdate. A new uAPI header, <uapi/linux/liveupdate.h>, will define the necessary structures. The magic number for IOCTL is registered in Documentation/userspace-api/ioctl/ioctl-number.rst. Link: https://lkml.kernel.org/r/20251125165850.3389713-1-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20251125165850.3389713-2-pasha.tatashin@soleen.com Link: https://lore.kernel.org/all/20251018000713.677779-1-vipinsh@google.com/ [1] Link: https://lore.kernel.org/linux-iommu/20250928190624.3735830-1-skhawaja@google.com [2] Link: https://lore.kernel.org/linux-pci/20250916-luo-pci-v2-0-c494053c3c08@kernel.org [3] Link: https://github.com/googleprodkernel/linux-liveupdate/tree/luo/v8 [4] Link: https://tinyurl.com/luoddesign [5] Link: https://lore.kernel.org/all/20251020100306.2709352-1-jasonmiu@google.com [6] Link: https://lore.kernel.org/all/20251115233409.768044-1-pasha.tatashin@soleen.com [7] Link: https://github.com/soleen/linux/blob/luo/v8b03/diff.v7.v8 [8] Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Pratyush Yadav <pratyush@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Tested-by: David Matlack <dmatlack@google.com> Cc: Aleksander Lobakin <aleksander.lobakin@intel.com> Cc: Alexander Graf <graf@amazon.com> Cc: Alice Ryhl <aliceryhl@google.com> Cc: Andriy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: anish kumar <yesanishhere@gmail.com> Cc: Anna Schumaker <anna.schumaker@oracle.com> Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Betkov <bp@alien8.de> Cc: Chanwoo Choi <cw00.choi@samsung.com> Cc: Chen Ridong <chenridong@huawei.com> Cc: Chris Li <chrisl@kernel.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Daniel Wagner <wagi@kernel.org> Cc: Danilo Krummrich <dakr@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Jeffery <djeffery@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guixin Liu <kanie@linux.alibaba.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joanthan Cameron <Jonathan.Cameron@huawei.com> Cc: Joel Granados <joel.granados@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lennart Poettering <lennart@poettering.net> Cc: Leon Romanovsky <leon@kernel.org> Cc: Leon Romanovsky <leonro@nvidia.com> Cc: Lukas Wunner <lukas@wunner.de> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Matthew Maurer <mmaurer@google.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Myugnjoo Ham <myungjoo.ham@samsung.com> Cc: Parav Pandit <parav@nvidia.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Saeed Mahameed <saeedm@nvidia.com> Cc: Samiullah Khawaja <skhawaja@google.com> Cc: Song Liu <song@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Stuart Hayes <stuart.w.hayes@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Weißschuh <linux@weissschuh.net> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: William Tu <witu@nvidia.com> Cc: Yoann Congal <yoann.congal@smile.fr> Cc: Zijun Hu <quic_zijuhu@quicinc.com> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Zhu Yanjun <yanjun.zhu@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-15powerpc/pseries: Define papr-hvpipe ioctlHaren Myneni1-0/+2
PowerPC FW introduced HVPIPE RTAS calls such as ibm,send-hvpipe-msg and ibm,receive-hvpipe-msg for the user space to exchange information with different sources such as Hardware Management Consoles (HMC). HVPIPE_IOC_CREATE_HANDLE is defined to use /dev/papr-hvpipe interface for ibm,send-hvpipe-msg and ibm,receive-hvpipe-msg RTAS calls. Also defined papr_hvpipe_hdr which will added in the payload that is passed between the kernel and the user space. Signed-off-by: Haren Myneni <haren@linux.ibm.com> Tested-by: Shashank MS <shashank.gowda@in.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20250909084402.1488456-2-haren@linux.ibm.com
2025-07-31Merge tag 'docs-6.17' of git://git.lwn.net/linuxLinus Torvalds1-273/+277
Pull documentation updates from Jonathan Corbet: "It has been a relatively busy cycle for docs, especially the build system: - The Perl kernel-doc script was added to 2.3.52pre1 just after the turn of the millennium. Over the following 25 years, it accumulated a vast amount of cruft, all in a language few people want to deal with anymore. Mauro's Python replacement in 6.16 faithfully reproduced all of the cruft in the hope of avoiding regressions. Now that we have a more reasonable code base, though, we can work on cleaning it up; many of the changes this time around are toward that end. - A reorganization of the ext4 docs into the usual TOC format. - Various Chinese translations and updates. - A new script from Mauro to help with docs-build testing. - A new document for linked lists - A sweep through MAINTAINERS fixing broken GitHub git:// repository links. ...and lots of fixes and updates" * tag 'docs-6.17' of git://git.lwn.net/linux: (147 commits) scripts: add origin commit identification based on specific patterns sphinx: kernel_abi: fix performance regression with O=<dir> Documentation: core-api: entry: Replace deprecated KVM entry/exit functions docs: fault-injection: drop reference to md-faulty docs: document linked lists scripts: kdoc: make it backward-compatible with Python 3.7 docs: kernel-doc: emit warnings for ancient versions of Python Documentation/rtla: Describe exit status Documentation/rtla: Add include common_appendix.rst docs: kernel: Clarify printk_ratelimit_burst reset behavior Documentation: ioctl-number: Don't repeat macro names Documentation: ioctl-number: Shorten macros table Documentation: ioctl-number: Correct full path to papr-physical-attestation.h Documentation: ioctl-number: Extend "Include File" column width Documentation: ioctl-number: Fix linuxppc-dev mailto link overlayfs.rst: fix typos docs: kdoc: emit a warning for ancient versions of Python docs: kdoc: clean up check_sections() docs: kdoc: directly access the always-there KdocItem fields docs: kdoc: straighten up dump_declaration() ...
2025-07-15Documentation: ioctl-number: Don't repeat macro namesBagas Sanjaya1-10/+12
Don't repeat mentioning macro names (_IO, _IOW, _IOR, and _IOWR) to keep the wording effective. Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250715024258.16882-3-bagasdotme@gmail.com
2025-07-15Documentation: ioctl-number: Shorten macros tableBagas Sanjaya1-6/+8
The macros table has three columns: the second one is "an" and the third one writes "an ioctl with ... parameters". Simplify the table by adding heading row that indicates macro name and accepted parameters. Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250715024258.16882-2-bagasdotme@gmail.com
2025-07-15Documentation: ioctl-number: Correct full path to papr-physical-attestation.hBagas Sanjaya1-1/+1
Commit 03c9d1a5a30d93 ("Documentation: Fix description format for powerpc RTAS ioctls") fixes Sphinx warning by chopping arch/ path component of papr-physical-attestation.h to fit existing "Include File" column. Now that the column has been widened just enough for that header file, add back its arch/ path component. Reviewed-by: Haren Myneni <haren@linux.ibm.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250714015711.14525-4-bagasdotme@gmail.com
2025-07-15Documentation: ioctl-number: Extend "Include File" column widthBagas Sanjaya1-258/+258
Extend width of "Include File" column to fit full path to papr-physical-attestation.h in later commit. Reviewed-by: Haren Myneni <haren@linux.ibm.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250714015711.14525-3-bagasdotme@gmail.com
2025-07-15Documentation: ioctl-number: Fix linuxppc-dev mailto linkBagas Sanjaya1-5/+5
Spell out full Linux PPC mailing list address like other subsystem mailing lists listed in the table. Reviewed-by: Haren Myneni <haren@linux.ibm.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250714015711.14525-2-bagasdotme@gmail.com
2025-07-07block: remove pktcdvd driverJens Axboe1-1/+0
This driver has long outlived it's utility, and it's broken and unloved. The main use case for this was direct mount with UDF of cd-rw drives that required 32kb packets. It would collect writes into that size and write them out in multiples of that. That's not a common use case anymore, the world has moved on from those kinds of media. To make matters worse, it's actively breaking setups where it's not even required or useful. Link: https://lore.kernel.org/linux-block/fxg6dksau4jsk3u5xldlyo2m7qgiux6vtdrz5rywseotsouqdv@urcrwz6qtd3r/ Link: https://lore.kernel.org/linux-block/dcc4836e-6da9-4208-ad27-bbd44b3a2063@kernel.dk/ Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-06-06Merge tag 'char-misc-6.16-rc1' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char / misc / iio driver updates from Greg KH: "Here is the big char/misc/iio and other small driver subsystem pull request for 6.16-rc1. Overall, a lot of individual changes, but nothing major, just the normal constant forward progress of new device support and cleanups to existing subsystems. Highlights in here are: - Large IIO driver updates and additions and device tree changes - Android binder bugfixes and logfile fixes - mhi driver updates - comedi driver updates - counter driver updates and additions - coresight driver updates and additions - echo driver removal as there are no in-kernel users of it - nvmem driver updates - spmi driver updates - new amd-sbi driver "subsystem" and drivers added - rust miscdriver binding documentation fix - other small driver fixes and updates (uio, w1, acrn, hpet, xillybus, cardreader drivers, fastrpc and others) All of these have been in linux-next for quite a while with no reported problems" * tag 'char-misc-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (390 commits) binder: fix yet another UAF in binder_devices counter: microchip-tcb-capture: Add watch validation support dt-bindings: iio: adc: Add ROHM BD79100G iio: adc: add support for Nuvoton NCT7201 dt-bindings: iio: adc: add NCT7201 ADCs iio: chemical: Add driver for SEN0322 dt-bindings: trivial-devices: Document SEN0322 iio: adc: ad7768-1: reorganize driver headers iio: bmp280: zero-init buffer iio: ssp_sensors: optimalize -> optimize HID: sensor-hub: Fix typo and improve documentation iio: admv1013: replace redundant ternary operator with just len iio: chemical: mhz19b: Fix error code in probe() iio: adc: at91-sama5d2: use IIO_DECLARE_BUFFER_WITH_TS iio: accel: sca3300: use IIO_DECLARE_BUFFER_WITH_TS iio: adc: ad7380: use IIO_DECLARE_DMA_BUFFER_WITH_TS iio: adc: ad4695: rename AD4695_MAX_VIN_CHANNELS iio: adc: ad4695: use IIO_DECLARE_DMA_BUFFER_WITH_TS iio: introduce IIO_DECLARE_BUFFER_WITH_TS macros iio: make IIO_DMA_MINALIGN minimum of 8 bytes ...
2025-05-27Merge tag 'docs-6.16' of git://git.lwn.net/linuxLinus Torvalds1-7/+6
Pull documentation updates from Jonathan Corbet: "A moderately busy cycle for documentation this time around: - The most significant change is the replacement of the old kernel-doc script (a monstrous collection of Perl regexes that predates the Git era) with a Python reimplementation. That, too, is a horrifying collection of regexes, but in a much cleaner and more maintainable structure that integrates far better with the Sphinx build system. This change has been in linux-next for the full 6.15 cycle; the small number of problems that turned up have been addressed, seemingly to everybody's satisfaction. The Perl kernel-doc script remains in tree (as scripts/kernel-doc.pl) and can be used with a command-line option if need be. Unless some reason to keep it around materializes, it will probably go away in 6.17. Credit goes to Mauro Carvalho Chehab for doing all this work. - Some RTLA documentation updates - A handful of Chinese translations - The usual collection of typo fixes, general updates, etc" * tag 'docs-6.16' of git://git.lwn.net/linux: (85 commits) Docs: doc-guide: update sphinx.rst Sphinx version number docs: doc-guide: clarify latest theme usage Documentation/scheduler: Fix typo in sched-stats domain field description scripts: kernel-doc: prevent a KeyError when checking output docs: kerneldoc.py: simplify exception handling logic MAINTAINERS: update linux-doc entry to cover new Python scripts docs: align with scripts/syscall.tbl migration Documentation: NTB: Fix typo Documentation: ioctl-number: Update table intro docs: conf.py: drop backward support for old Sphinx versions Docs: driver-api/basics: add kobject_event interfaces Docs: relay: editing cleanups docs: fix "incase" typo in coresight/panic.rst Fix spelling error for 'parallel' docs: admin-guide: fix typos in reporting-issues.rst docs: dmaengine: add explanation for DMA_ASYNC_TX capability Documentation: leds: improve readibility of multicolor doc docs: fix typo in firmware-related section docs: Makefile: Inherit PYTHONPYCACHEPREFIX setting as env variable Documentation: ioctl-number: Update outdated submission info ...
2025-05-21misc: amd-sbi: Add support for AMD_SBI IOCTLAkshay Gupta1-0/+2
The present sbrmi module only support reporting power via hwmon. However, AMD data center range of processors support various system management functionality using custom protocols defined in Advanced Platform Management Link (APML) specification. Register a miscdevice, which creates a device /dev/sbrmiX with an IOCTL interface for the user space to invoke the APML Mailbox protocol, which is already defined in sbrmi_mailbox_xfer(). The APML protocols depend on a set of RMI registers. Having an IOCTL as a single entry point will help in providing synchronization among these protocols as multiple transactions on RMI register set may create race condition. Support for other protocols will be added in subsequent patches. APML mailbox protocol returns additional error codes written by SMU firmware in the out-bound register 0x37. These errors include, invalid core, message not supported over platform and others. This additional error codes can be used to provide more details to user space. Open-sourced and widely used https://github.com/amd/esmi_oob_library will continue to provide user-space programmable API. Reviewed-by: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com> Signed-off-by: Akshay Gupta <akshay.gupta@amd.com> Link: https://lore.kernel.org/r/20250428063034.2145566-7-akshay.gupta@amd.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-19Documentation: ioctl-number: Update table introBagas Sanjaya1-3/+2
Introduction paragraph to the ioctl numbers table states that only ioctls in up to ancient Linux kernel version (v2.6.31) for x86 arch are listed. This is inaccurate as the table also lists ioctls from non-x86 archs and the kernel is continously developed (currently in v6.x). Update the paragraph accordingly. Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20250508005838.8381-2-bagasdotme@gmail.com>
2025-05-07Documentation: ioctl-number: Update outdated submission infoBagas Sanjaya1-4/+4
Much like device numbers that used to be assigned by LANANA (see commit ebdf4040c16df5 ("Documentation: update the devices.txt documentation"), ioctl numbers list is maintained by general kernel community nowadays instead of contacting Michael directly as he's long stepped down from kernel-related activity (his last LKML message was from 2003 [1] and he's in CREDITS since the beginning of kernel's git history). Also, patch (including one to update ioctl numbers list) submission now follows process as described in Documentation/process/submitting-patches.rst rather than sending patches directly to Linus as in the distant past. Update the docs to reflect that. Link: https://lore.kernel.org/r/200305261446.h4QEkBVv023861@duracef.shout.net/ [1] Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20250502074504.26933-2-bagasdotme@gmail.com>
2025-05-02Documentation: Fix description format for powerpc RTAS ioctlsHaren Myneni1-3/+3
Fix the description format for the following build warnings: "Documentation/userspace-api/ioctl/ioctl-number.rst:369: ERROR: Malformed table. Text in column margin in table line 301. 0xB2 03-05 arch/powerpc/include/uapi/asm/papr-indices.h powerpc/pseries indices API <mailto:linuxppc-dev> 0xB2 06-07 arch/powerpc/include/uapi/asm/papr-platform-dump.h powerpc/pseries Platform Dump API <mailto:linuxppc-dev> 0xB2 08 arch/powerpc/include/uapi/asm/papr-physical-attestation.h powerpc/pseries Physical Attestation API <mailto:linuxppc-dev>" Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Haren Myneni <haren@linux.ibm.com> Fixes: 43d869ac25f1 ("powerpc/pseries: Define papr_indices_io_block for papr-indices ioctls") Fixes: 8aa9efc0be66 ("powerpc/pseries: Add papr-platform-dump character driver for dump retrieval") Fixes: 86900ab620a4 ("powerpc/pseries: Add a char driver for physical-attestation RTAS") Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Closes: https://lore.kernel.org/linux-next/20250429181707.7848912b@canb.auug.org.au/ Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20250430022847.1118093-1-haren@linux.ibm.com
2025-04-17powerpc/pseries: Add a char driver for physical-attestation RTASHaren Myneni1-0/+2
The RTAS call ibm,physical-attestation is used to retrieve information about the trusted boot state of the firmware and hypervisor on the system, and also Trusted Platform Modules (TPM) data if the system is TCG 2.0 compliant. This RTAS interface expects the caller to define different command structs such as RetrieveTPMLog, RetrievePlatformCertificat and etc, in a work area with a maximum size of 4K bytes and the response buffer will be returned in the same work area. The current implementation of this RTAS function is in the user space but allocation of the work area is restricted with the system lockdown. So this patch implements this RTAS function in the kernel and expose to the user space with open/ioctl/read interfaces. PAPR (2.13+ 21.3 ibm,physical-attestation) defines RTAS function: - Pass the command struct to obtain the response buffer for the specific command. - This RTAS function is sequence RTAS call and has to issue RTAS call multiple times to get the complete response buffer (max 64K). The hypervisor expects the first RTAS call with the sequence 1 and the subsequent calls with the sequence number returned from the previous calls. Expose these interfaces to user space with a /dev/papr-physical-attestation character device using the following programming model: int devfd = open("/dev/papr-physical-attestation"); int fd = ioctl(devfd, PAPR_PHY_ATTEST_IOC_HANDLE, struct papr_phy_attest_io_block); - The user space defines the command struct and requests the response for any command. - Obtain the complete response buffer and returned the buffer as blob to the command specific FD. size = read(fd, buf, len); - Can retrieve the response buffer once or multiple times until the end of BLOB buffer. Implemented this new kernel ABI support in librtas library for system lockdown Signed-off-by: Haren Myneni <haren@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20250416225743.596462-8-haren@linux.ibm.com
2025-04-17powerpc/pseries: Add papr-platform-dump character driver for dump retrievalHaren Myneni1-0/+2
ibm,platform-dump RTAS call in combination with writable mapping /dev/mem is issued to collect platform dump from the hypervisor and may need multiple calls to get the complete dump. The current implementation uses rtas_platform_dump() API provided by librtas library to issue these RTAS calls. But /dev/mem access by the user space is prohibited under system lockdown. The solution should be to restrict access to RTAS function in user space and provide kernel interfaces to collect dump. This patch adds papr-platform-dump character driver and expose standard interfaces such as open / ioctl/ read to user space in ways that are compatible with lockdown. PAPR (7.3.3.4.1 ibm,platform-dump) provides a method to obtain the complete dump: - Each dump will be identified by ID called dump tag. - A sequence of RTAS calls have to be issued until retrieve the complete dump. The hypervisor expects the first RTAS call with the sequence 0 and the subsequent calls with the sequence number returned from the previous calls. - The hypervisor returns "dump complete" status once the complete dump is retrieved. But expects one more RTAS call from the partition with the NULL buffer to invalidate dump which means the dump will be removed in the hypervisor. - Sequence of calls are allowed with different dump IDs at the same time but not with the same dump ID. Expose these interfaces to user space with a /dev/papr-platform-dump character device using the following programming model: int devfd = open("/dev/papr-platform-dump", O_RDONLY); int fd = ioctl(devfd,PAPR_PLATFORM_DUMP_IOC_CREATE_HANDLE, &dump_id) - Restrict user space to access with the same dump ID. Typically we do not expect user space requests the dump again for the same dump ID. char *buf = malloc(size); length = read(fd, buf, size); - size should be minimum 1K based on PAPR and <= 4K based on RTAS work area size. It will be restrict to RTAS work area size. Using 4K work area based on the current implementation in librtas library - Each read call issue RTAS call to get the data based on the size requirement and returns bytes returned from the hypervisor - If the previous call returns dump complete status, the next read returns 0 like EOF. ret = ioctl(PAPR_PLATFORM_DUMP_IOC_INVALIDATE, &dump_id) - RTAS call with NULL buffer to invalidates the dump. The read API should use the file descriptor obtained from ioctl based on dump ID so that gets dump contents for the corresponding dump ID. Implemented support in librtas (rtas_platform_dump()) for this new ABI to support system lockdown. Signed-off-by: Haren Myneni <haren@linux.ibm.com> Tested-by: Sathvika Vasireddy <sv@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20250416225743.596462-7-haren@linux.ibm.com
2025-04-17powerpc/pseries: Define papr_indices_io_block for papr-indices ioctlsHaren Myneni1-0/+2
To issue ibm,get-indices, ibm,set-dynamic-indicator and ibm,get-dynamic-sensor-state in the user space, the RMO buffer is allocated for the work area which is restricted under system lockdown. So instead of user space execution, the kernel will provide /dev/papr-indices interface to execute these RTAS calls. The user space assigns data in papr_indices_io_block struct depends on the specific HCALL and passes to the following ioctls: PAPR_INDICES_IOC_GET: Use for ibm,get-indices. Returns a get-indices handle fd to read data. PAPR_DYNAMIC_SENSOR_IOC_GET: Use for ibm,get-dynamic-sensor-state. Updates the sensor state in papr_indices_io_block.dynamic_param.state PAPR_DYNAMIC_INDICATOR_IOC_SET: Use for ibm,set-dynamic-indicator. Sets the new state for the input indicator. Signed-off-by: Haren Myneni <haren@linux.ibm.com> Tested-by: Sathvika Vasireddy <sv@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20250416225743.596462-3-haren@linux.ibm.com
2025-04-02Merge tag 'powerpc-6.15-2' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull more powerpc updates from Michael Ellerman: - Remove the IBM CAPI (cxl) driver Thanks to Andrew Donnellan. * tag 'powerpc-6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: docs: Fix references to IBM CAPI (cxl) removal version cxl: Remove driver
2025-04-02docs: Fix references to IBM CAPI (cxl) removal versionMichael Ellerman1-2/+2
The IBM CAPI (cxl) driver was removed in 6.15, not 6.14. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2025-04-02Merge branch 'topic/cxl' into nextMichael Ellerman1-1/+1
This merges in the removal of the IBM CAPI "cxl" driver.
2025-03-29Merge tag 'for-linus-fwctl' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma Pull fwctl subsystem from Jason Gunthorpe: "fwctl is a new subsystem intended to bring some common rules and order to the growing pattern of exposing a secure FW interface directly to userspace. Unlike existing places like RDMA/DRM/VFIO/uacce that are exposing a device for datapath operations fwctl is focused on debugging, configuration and provisioning of the device. It will not have the necessary features like interrupt delivery to support a datapath. This concept is similar to the long standing practice in the "HW" RAID space of having a device specific misc device to manage the RAID controller FW. fwctl generalizes this notion of a companion debug and management interface that goes along with a dataplane implemented in an appropriate subsystem. There have been three LWN articles written discussing various aspects of this: https://lwn.net/Articles/955001/ https://lwn.net/Articles/969383/ https://lwn.net/Articles/990802/ This includes three drivers to launch the subsystem: - CXL provides a vendor scheme for executing commands and a way to learn the 'command effects' (ie the security properties) of such commands. The fwctl driver allows access to these mechanism within the fwctl security model - mlx5 is family of networking products, the driver supports all current Mellanox HW still receiving FW feature updates. This includes RDMA multiprotocol NICs like ConnectX and the Bluefield family of Smart NICs. - AMD/Pensando Distributed Services card is a multi protocol Smart NIC with a multi PCI function design. fwctl works on the management PCI function following a 'command effects' model similar to CXL" * tag 'for-linus-fwctl' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (30 commits) pds_fwctl: add Documentation entries pds_fwctl: add rpc and query support pds_fwctl: initial driver framework pds_core: add new fwctl auxiliary_device pds_core: specify auxiliary_device to be created pds_core: make pdsc_auxbus_dev_del() void cxl: Fixup kdoc issues for include/cxl/features.h fwctl/cxl: Add documentation to FWCTL CXL cxl/test: Add Set Feature support to cxl_test cxl/test: Add Get Feature support to cxl_test cxl: Add support to handle user feature commands for set feature cxl: Add support to handle user feature commands for get feature cxl: Add support for fwctl RPC command to enable CXL feature commands cxl: Move cxl feature command structs to user header cxl: Add FWCTL support to CXL mlx5: Create an auxiliary device for fwctl_mlx5 fwctl/mlx5: Support for communicating with mlx5 fw fwctl: Add documentation fwctl: FWCTL_RPC to execute a Remote Procedure Call to device firmware taint: Add TAINT_FWCTL ...
2025-03-26Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds1-1/+1
Pull SCSI updates from James Bottomley: "Updates to the usual drivers (scsi_debug, ufs, lpfc, st, fnic, mpi3mr, mpt3sas) and the removal of cxlflash. The only non-trivial core change is an addition to unit attention handling to recognize UAs for power on/reset and new media so the tape driver can use it" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (107 commits) scsi: st: Tighten the page format heuristics with MODE SELECT scsi: st: ERASE does not change tape location scsi: st: Fix array overflow in st_setup() scsi: target: tcm_loop: Fix wrong abort tag scsi: lpfc: Restore clearing of NLP_UNREG_INP in ndlp->nlp_flag scsi: hisi_sas: Fixed failure to issue vendor specific commands scsi: fnic: Remove unnecessary NUL-terminations scsi: fnic: Remove redundant flush_workqueue() calls scsi: core: Use a switch statement when attaching VPD pages scsi: ufs: renesas: Add initialization code for R-Car S4-8 ES1.2 scsi: ufs: renesas: Add reusable functions scsi: ufs: renesas: Refactor 0x10ad/0x10af PHY settings scsi: ufs: renesas: Remove register control helper function scsi: ufs: renesas: Add register read to remove save/set/restore scsi: ufs: renesas: Replace init data by init code scsi: ufs: dt-bindings: renesas,ufs: Add calibration data scsi: mpi3mr: Task Abort EH Support scsi: storvsc: Don't report the host packet status as the hv status scsi: isci: Make most module parameters static scsi: megaraid_sas: Make most module parameters static ...
2025-03-26Merge tag 'for-6.15/block-20250322' of git://git.kernel.dk/linuxLinus Torvalds1-0/+2
Pull block updates from Jens Axboe: - Fixes for integrity handling - NVMe pull request via Keith: - Secure concatenation for TCP transport (Hannes) - Multipath sysfs visibility (Nilay) - Various cleanups (Qasim, Baruch, Wang, Chen, Mike, Damien, Li) - Correct use of 64-bit BARs for pci-epf target (Niklas) - Socket fix for selinux when used in containers (Peijie) - MD pull request via Yu: - fix recovery can preempt resync (Li Nan) - fix md-bitmap IO limit (Su Yue) - fix raid10 discard with REQ_NOWAIT (Xiao Ni) - fix raid1 memory leak (Zheng Qixing) - fix mddev uaf (Yu Kuai) - fix raid1,raid10 IO flags (Yu Kuai) - some refactor and cleanup (Yu Kuai) - Series cleaning up and fixing bugs in the bad block handling code - Improve support for write failure simulation in null_blk - Various lock ordering fixes - Fixes for locking for debugfs attributes - Various ublk related fixes and improvements - Cleanups for blk-rq-qos wait handling - blk-throttle fixes - Fixes for loop dio and sync handling - Fixes and cleanups for the auto-PI code - Block side support for hardware encryption keys in blk-crypto - Various cleanups and fixes * tag 'for-6.15/block-20250322' of git://git.kernel.dk/linux: (105 commits) nvmet: replace max(a, min(b, c)) by clamp(val, lo, hi) nvme-tcp: fix selinux denied when calling sock_sendmsg nvmet: pci-epf: Always configure BAR0 as 64-bit nvmet: Remove duplicate uuid_copy nvme: zns: Simplify nvme_zone_parse_entry() nvmet: pci-epf: Remove redundant 'flush_workqueue()' calls nvmet-fc: Remove unused functions nvme-pci: remove stale comment nvme-fc: Utilise min3() to simplify queue count calculation nvme-multipath: Add visibility for queue-depth io-policy nvme-multipath: Add visibility for numa io-policy nvme-multipath: Add visibility for round-robin io-policy nvmet: add tls_concat and tls_key debugfs entries nvmet-tcp: support secure channel concatenation nvmet: Add 'sq' argument to alloc_ctrl_args nvme-fabrics: reset admin connection for secure concatenation nvme-tcp: request secure channel concatenation nvme-keyring: add nvme_tls_psk_refresh() nvme: add nvme_auth_derive_tls_psk() nvme: add nvme_auth_generate_digest() ...
2025-03-21Drivers: hv: Introduce mshv_root module to expose /dev/mshv to VMMsNuno Das Neves1-0/+2
Provide a set of IOCTLs for creating and managing child partitions when running as root partition on Hyper-V. The new driver is enabled via CONFIG_MSHV_ROOT. A brief overview of the interface: MSHV_CREATE_PARTITION is the entry point, returning a file descriptor representing a child partition. IOCTLs on this fd can be used to map memory, create VPs, etc. Creating a VP returns another file descriptor representing that VP which in turn has another set of corresponding IOCTLs for running the VP, getting/setting state, etc. MSHV_ROOT_HVCALL is a generic "passthrough" hypercall IOCTL which can be used for a number of partition or VP hypercalls. This is for hypercalls that do not affect any state in the kernel driver, such as getting and setting VP registers and partition properties, translating addresses, etc. It is "passthrough" because the binary input and output for the hypercall is only interpreted by the VMM - the kernel driver does nothing but insert the VP and partition id where necessary (which are always in the same place), and execute the hypercall. Co-developed-by: Anirudh Rayabharam <anrayabh@linux.microsoft.com> Signed-off-by: Anirudh Rayabharam <anrayabh@linux.microsoft.com> Co-developed-by: Jinank Jain <jinankjain@microsoft.com> Signed-off-by: Jinank Jain <jinankjain@microsoft.com> Co-developed-by: Mukesh Rathor <mrathor@linux.microsoft.com> Signed-off-by: Mukesh Rathor <mrathor@linux.microsoft.com> Co-developed-by: Muminul Islam <muislam@microsoft.com> Signed-off-by: Muminul Islam <muislam@microsoft.com> Co-developed-by: Praveen K Paladugu <prapal@linux.microsoft.com> Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com> Co-developed-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Signed-off-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Co-developed-by: Wei Liu <wei.liu@kernel.org> Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com> Reviewed-by: Roman Kisel <romank@linux.microsoft.com> Link: https://lore.kernel.org/r/1741980536-3865-11-git-send-email-nunodasneves@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <1741980536-3865-11-git-send-email-nunodasneves@linux.microsoft.com>
2025-03-16cxl: Remove driverAndrew Donnellan1-1/+1
Remove the cxl driver that provides support for the IBM Coherent Accelerator Processor Interface. Revert or clean up associated code in arch/powerpc that is no longer necessary. cxl has received minimal maintenance for several years, and is not supported on the Power10 processor. We aren't aware of any users who are likely to be using recent kernels. Thanks to Mikey Neuling, Ian Munsie, Daniel Axtens, Frederic Barrat, Christophe Lombard, Philippe Bergheaud, Vaibhav Jain and Alastair D'Silva for their work on this driver over the years. Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.ibm.com> Acked-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20250219070007.177725-2-ajd@linux.ibm.com
2025-03-06fwctl: Basic ioctl dispatch for the character deviceJason Gunthorpe1-0/+1
Each file descriptor gets a chunk of per-FD driver specific context that allows the driver to attach a device specific struct to. The core code takes care of the memory lifetime for this structure. The ioctl dispatch and design is based on what was built for iommufd. The ioctls have a struct which has a combined in/out behavior with a typical 'zero pad' scheme for future extension and backwards compatibility. Like iommufd some shared logic does most of the ioctl marshaling and compatibility work and table dispatches to some function pointers for each unique ioctl. This approach has proven to work quite well in the iommufd and rdma subsystems. Allocate an ioctl number space for the subsystem. Link: https://patch.msgid.link/r/2-v5-642aa0c94070+4447f-fwctl_jgg@nvidia.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Shannon Nelson <shannon.nelson@amd.com> Tested-by: Dave Jiang <dave.jiang@intel.com> Tested-by: Shannon Nelson <shannon.nelson@amd.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2025-02-10blk-crypto: add ioctls to create and prepare hardware-wrapped keysEric Biggers1-0/+2
Until this point, the kernel can use hardware-wrapped keys to do encryption if userspace provides one -- specifically a key in ephemerally-wrapped form. However, no generic way has been provided for userspace to get such a key in the first place. Getting such a key is a two-step process. First, the key needs to be imported from a raw key or generated by the hardware, producing a key in long-term wrapped form. This happens once in the whole lifetime of the key. Second, the long-term wrapped key needs to be converted into ephemerally-wrapped form. This happens each time the key is "unlocked". In Android, these operations are supported in a generic way through KeyMint, a userspace abstraction layer. However, that method is Android-specific and can't be used on other Linux systems, may rely on proprietary libraries, and also misleads people into supporting KeyMint features like rollback resistance that make sense for other KeyMint keys but don't make sense for hardware-wrapped inline encryption keys. Therefore, this patch provides a generic kernel interface for these operations by introducing new block device ioctls: - BLKCRYPTOIMPORTKEY: convert a raw key to long-term wrapped form. - BLKCRYPTOGENERATEKEY: have the hardware generate a new key, then return it in long-term wrapped form. - BLKCRYPTOPREPAREKEY: convert a key from long-term wrapped form to ephemerally-wrapped form. These ioctls are implemented using new operations in blk_crypto_ll_ops. Signed-off-by: Eric Biggers <ebiggers@google.com> Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> # sm8650 Link: https://lore.kernel.org/r/20250204060041.409950-4-ebiggers@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-03scsi: cxlflash: Remove driverAndrew Donnellan1-1/+1
Remove the cxlflash driver for IBM CAPI Flash devices. The cxlflash driver has received minimal maintenance for some time, and the CAPI Flash hardware that uses it is no longer commercially available. Thanks to Uma Krishnan, Matthew Ochs and Manoj Kumar for their work on this driver over the years. Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Link: https://lore.kernel.org/r/20250203072801.365551-2-ajd@linux.ibm.com Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2025-01-28Merge tag 'driver-core-6.14-rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core and debugfs updates from Greg KH: "Here is the big set of driver core and debugfs updates for 6.14-rc1. Included in here is a bunch of driver core, PCI, OF, and platform rust bindings (all acked by the different subsystem maintainers), hence the merge conflict with the rust tree, and some driver core api updates to mark things as const, which will also require some fixups due to new stuff coming in through other trees in this merge window. There are also a bunch of debugfs updates from Al, and there is at least one user that does have a regression with these, but Al is working on tracking down the fix for it. In my use (and everyone else's linux-next use), it does not seem like a big issue at the moment. Here's a short list of the things in here: - driver core rust bindings for PCI, platform, OF, and some i/o functions. We are almost at the "write a real driver in rust" stage now, depending on what you want to do. - misc device rust bindings and a sample driver to show how to use them - debugfs cleanups in the fs as well as the users of the fs api for places where drivers got it wrong or were unnecessarily doing things in complex ways. - driver core const work, making more of the api take const * for different parameters to make the rust bindings easier overall. - other small fixes and updates All of these have been in linux-next with all of the aforementioned merge conflicts, and the one debugfs issue, which looks to be resolved "soon"" * tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits) rust: device: Use as_char_ptr() to avoid explicit cast rust: device: Replace CString with CStr in property_present() devcoredump: Constify 'struct bin_attribute' devcoredump: Define 'struct bin_attribute' through macro rust: device: Add property_present() saner replacement for debugfs_rename() orangefs-debugfs: don't mess with ->d_name octeontx2: don't mess with ->d_parent or ->d_parent->d_name arm_scmi: don't mess with ->d_parent->d_name slub: don't mess with ->d_name sof-client-ipc-flood-test: don't mess with ->d_name qat: don't mess with ->d_name xhci: don't mess with ->d_iname mtu3: don't mess wiht ->d_iname greybus/camera - stop messing with ->d_iname mediatek: stop messing with ->d_iname netdevsim: don't embed file_operations into your structs b43legacy: make use of debugfs_get_aux() b43: stop embedding struct file_operations into their objects carl9170: stop embedding file_operations into their objects ...
2025-01-10pps: adjust references to actual name of uapi header fileLukas Bulwahn1-1/+1
Commit 86b525bed275 ("drivers pps: add PPS generators support") adds a file entry in MAINTAINERS and a reference in the ioctl-number documentation referring to the file pps-gen.h, whereas the file added in this commit is named pps_gen.h. Adjust the two references to the actual name of the uapi header file. While at it, put the entry in MAINTAINERS at the right place for alphabetical ordering. Fixes: 86b525bed275 ("drivers pps: add PPS generators support") Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com> Link: https://lore.kernel.org/r/20250110105000.56228-1-lukas.bulwahn@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-08drivers pps: add PPS generators supportRodolfo Giometti1-0/+1
Sometimes one needs to be able not only to catch PPS signals but to produce them also. For example, running a distributed simulation, which requires computers' clock to be synchronized very tightly. This patch adds PPS generators class in order to have