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2 daysMerge tag 'ntfs-for-7.4-rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/ntfs Pull ntfs updates from Namjae Jeon: "New features: - Implement ioctls to list, read, write, and remove named streams on files and directories. Provide optional file:stream pathname access through streams_interface=windows, exposing streams as regular file descriptors with support for mmap, locking, truncation, and allocation. - Support file attribute queries and updates through FS_IOC_GETFLAGS and FS_IOC_SETFLAGS. Store immutable, append-only, nodump, and noatime settings in the private $LINUXFLAGS extended attribute and restore them when loading inodes. Also report compression, encryption, and the mount-wide case-folding policy as read-only attributes. Other changes: - Expose the existing NTFS volume serial number through FS_IOC_GETFSUUID by registering it as an eight-byte filesystem identifier. - Validate MFT I/O geometry and write MFT records and mirror data through mapped I/O units, keeping neighboring records intact when multiple records share a native 4Kn block. Track folio writeback until all BIOs complete, serialize raw record updates against writeback, and use the caller's requested completion mode. - Discard stale uninitialized cache data before extending initialized size, ensure shared mmap writes update initialized size after native 4Kn size extension, and synchronize attribute inode sizes after internal resizes. Keep VFS and NTFS sizes consistent when write-error rollback fails and record the volume error. - Wait for existing folio writeback before updating attribute data, require page alignment for full-page write optimizations, and include the final partial cluster in synchronous writes. Skip duplicate VFS page-cache truncation under the MFT record lock to avoid a truncate and writeback deadlock. - Restart allocation zone searches after failed hints and prevent contiguous allocation requests from returning additional disjoint runs that callers leave uninitialized. Allow fallocate after MFT-zone exhaustion and interrupt allocation loops only for fatal signals, avoiding spurious interruptions from io_uring task-work notifications. - Wait for the initial bitmap scan before extending the MFT bitmap, bound direct allocation candidates by the volume size, update free-space accounting, and undo only newly allocated clusters after run coalescing. Update attribute-list inode size before reserving additional space. - Hold runlist locks while expanding non-resident attributes, balance locks during MFT extension error handling, and avoid pointers invalidated by runlist reallocation. Keep source runlists available for rollback and allocate enough room for runlist markers and terminators. - Return errors for unmappable runlist fragments instead of treating them as holes or delayed allocation. Check non-resident attribute sizes against their allocation and fail mounts when $MFT needs extent records outside the decoded runlist to describe itself, preventing silent zero reads and mount hangs. - Load and validate $BadClus:$Bad at mount time and reserve known bad clusters before the free-space scan. Fall back to read-only operation when bad-cluster metadata cannot be validated and prevent subsequent read-write remounts. - Serialize volume flag updates and retain the dirty bit after metadata changes while the volume remains mounted read-write. Persist recorded errors after final metadata commits, fail ordinary read-only remounts on sync, commit, or flush errors, and retain the dirty bit on forced remounts. - Flush the device write cache when syncing directories and report flush failures from both file and directory fsync. Drain in-flight direct I/O before buffered write fallback and keep nonblocking requests from entering the blocking fallback path. - Mount hibernated volumes, or volumes whose hibernation state cannot be determined, read-only regardless of the errors= policy. Prevent mount-time and dirty-state updates from modifying hibernated volumes. - Validate complete EA chains, link zero-terminated tails when appending entries, retain the EA presence flag, and distinguish empty values from removal. Propagate lookup, write, and truncate errors, restore both EA attributes after failed updates, and shut down the volume if restoration fails. - Restore the previous ACL xattr when a subsequent WSL mode update fails, including replacement and removal cases. Record rollback failures so an unsuccessful permission change cannot silently leave inconsistent ACL and mode state. - Apply MST fixups to individual index blocks on large-page systems and use fixed 512-byte VCN units when an index block is smaller than its cluster. Support lookup and removal of POSIX names containing Windows-invalid characters and identify directory symlinks and junctions during enumeration. - Report the stored creation time for symbolic links through statx() when querying the link itself with AT_SYMLINK_NOFOLLOW. - Use wider decompression offsets to avoid overflow on 64 KB pages, accept the standard sparse compression unit, and require the compressed-size field only on the first attribute extent. Block direct reads and skip readahead for encrypted files to prevent returning raw ciphertext. - Validate index entry offsets, logfile update sequence array counts, attribute-list sizes, and index collation key lengths to prevent out-of-bounds accesses, NULL pointer dereferences, and excessive allocations from corrupt volume metadata. - Derive FITRIM bitmap indexes from the page size and retain the full 64-bit minimum discard length. Balance highmem mappings in logfile and MFT mirror checks and propagate specific errors from extent, attribute, and reparse operations. - Compare streams_interface with the mounted volume's setting during remount, make named-stream UAPI padding explicit, document stream access and Linux file attributes, and add the NTFS UAPI header to MAINTAINERS" * tag 'ntfs-for-7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/ntfs: (93 commits) ntfs: handle a failed size rollback in the write error path ntfs: fix u16 truncation of the update sequence array count check ntfs: reject index blocks with a too small entries offset ntfs: support persistent noatime attribute ntfs: roll back the ACL xattr commit when the WSL mode update fails ntfs: report birth time for symbolic links ntfs: support FS_IOC_GETFSUUID ntfs: avoid unnecessary padding in uapi structure ntfs: flush the block device when syncing a directory ntfs: report block device flush failures from fsync ntfs: fix NULL dereference on index allocation open failure ntfs: compare streams_interface with mounted volume on remount ntfs: widen the sub-block offsets in ntfs_decompress() ntfs: reject direct I/O reads of encrypted files ntfs: do not read ahead encrypted files ntfs: persist nodump in the $LINUXFLAGS EA ntfs: persist append-only in the $LINUXFLAGS EA ntfs: persist immutable in the $LINUXFLAGS EA ntfs: add fileattr query support ntfs: restore EA attributes when an update fails ...
3 daysMerge tag 'media/v7.4-1' of ↵Linus Torvalds3-0/+23
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media Pull media updates from Mauro Carvalho Chehab: - v4l2 core: - improve subdev and pixformat kAPI; - fix P010 format info and add Y12 format info; - add fwnode_graph_for_each_endpoint_scoped(); - New sensor drivers: - Sony IMX576 - OmniVision OS02G10, OV05C10 and OG0VA1B - Samsung S5KJN5 - Himax HM1246 - Maxim GMSL2/3: add support for MAX9296A, MAX96717, and MAX96724 - Intel IPU6: add support for IPU7, IPU7.5 and IPU8 - NXP: add support for i.MX95 CSI pixel formatter driver - ITE: add driver for IT6625/IT6626 HDMI bridge - Qualcomm: add CSI2 3ph DPHY driver - Rockchip: add rk3576 MIPI capture vicap driver - STM32 DCMIPP: Add STM32MP25 subdevices - Lots of driver fixes and cleanups * tag 'media/v7.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (596 commits) media: i2c: imx576: Fix line length register media: ov05c10: Remove duplicated writes to analogue gain register media: ov05c10: Power management fixes media: ov05c10: Set reset GPIO high when acquiring it media: ov05c10: Small cleanups media: maxim-serdes: Disable test pattern generator for now media: mc: Keep INTERNAL pad flags just for the kernel, for now media: i2c: imx576: select VIDEO_CCS_PLL to repair build error media: Documentation: mc: Fix Stream reference media: i2c: add imx576 image sensor driver dt-bindings: media: i2c: Add imx576 sensor media: i2c: maxim-serdes: add MAX9296A driver media: i2c: remove MAX96714 driver media: i2c: maxim-serdes: add MAX96724 driver staging: media: remove MAX96712 driver arm64: defconfig: disable deprecated MAX96712 driver media: i2c: maxim-serdes: add MAX96717 driver media: i2c: remove MAX96717 driver media: i2c: add Maxim GMSL2/3 deserializer framework media: i2c: add Maxim GMSL2/3 serializer framework ...
5 daysMerge tag 'seccomp-v7.4-rc1' of ↵Linus Torvalds1-0/+37
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull seccomp updates from Kees Cook: - allow addfd to transfer O_PATH descriptors (Cong Wang) - allow restarting interrupted unreceived notifications (Cong Wang) - fix SECCOMP_ADDFD_FLAG_SEND when interrupted (Hui Peng) - Various docs and test clean-ups * tag 'seccomp-v7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: selftests/seccomp: Split fork_and_close into clone and close tests seccomp: Document RESTART_BEFORE_RECV and O_PATH addfd selftests/seccomp: test addfd with an O_PATH descriptor seccomp: allow addfd to transfer O_PATH descriptors docs/seccomp: describe the SECCOMP_FILTER_FLAG_RESTART_BEFORE_RECV flag selftests/seccomp: cover restart of unreceived notifications seccomp: allow restarting interrupted unreceived notifications seccomp: restore knotif->state when SECCOMP_ADDFD_FLAG_SEND is interrupted
5 daysMerge tag 'landlock-7.4-rc1' of ↵Linus Torvalds1-13/+230
git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux Pull Landlock update from Mickaël Salaün: "The main change adds composable Landlock controls for namespace types and Linux capabilities, thanks to new LSM hooks (merged via the LSM tree). A umount race condition is also fixed" * tag 'landlock-7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux: landlock: Fix superblock use-after-free in release_inode() selftests/landlock: Fix snprintf truncation checks in test files landlock: Add documentation for capability and namespace restrictions samples/landlock: Add capability and namespace restriction support selftests/landlock: Add capability restriction tests selftests/landlock: Add namespace restriction tests landlock: Enforce capability restrictions landlock: Enforce namespace use restrictions landlock: Wrap per-layer access masks in struct layer_config landlock: Rename quiet_masks to quiet_access
8 dayslandlock: Add documentation for capability and namespace restrictionsMickaël Salaün1-13/+230
Document the two new Landlock permission categories, introduced with ABI 12, in the userspace API guide, admin guide, trace-event guide, UAPI comments, and kernel security documentation. The kernel security documentation generalizes the existing per-object access-rights framing into three restriction models (handled_access_*, handled_permissions, scoped) and states criteria for choosing among them, so future permission or scope additions have a documented place to land. Cc: Christian Brauner <brauner@kernel.org> Cc: Günther Noack <gnoack@google.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Serge E. Hallyn <serge@hallyn.com> Link: https://patch.msgid.link/20261014082718.1435842-9-mic@digikod.net Signed-off-by: Mickaël Salaün <mic@digikod.net>
8 daysntfs: add named stream ioctls supportNamjae Jeon1-0/+1
NTFS supports multiple named $DATA attributes, commonly known as alternate data streams. Add NTFS-specific ioctls to list, read, write, and remove named streams through an opened base file or directory. The UAPI provides separate commands for each operation. - NTFS_IOC_STREAM_READ - NTFS_IOC_STREAM_WRITE - NTFS_IOC_STREAM_REMOVE - NTFS_IOC_LIST_STREAMS Read and write requests use struct ntfs_stream to specify the stream name, byte offset, and transfer length. Writes create the stream if it does not already exist. A write failure after creation may leave the new stream visible. It is not rolled back because another caller may already have opened it. Userspace can remove it with NTFS_IOC_STREAM_REMOVE. The list command returns variable-length entries containing each named stream's data size, allocated size, and name. If the buffer is too small, the command returns -ENOSPC without copying entries. bytes_returned reports the required buffer size, and stream_count reports the number of streams. Stream names use the mounted filesystem NLS by default. Set NTFS_STREAM_FL_UTF16 to pass or receive raw UTF-16LE names. In NLS mode, names that cannot be represented by the mounted character set are omitted from the list. Use UTF-16 mode for lossless enumeration. Read and write transfers are limited to 16 MiB per request. Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2026-10-09media: Documentation: mc: Fix Stream referenceSakari Ailus1-2/+1
Fix referencing Stream in glossary. Fixes: 49cdf56876d3 ("media: mc: Add INTERNAL pad flag") Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
2026-10-06seccomp: Document RESTART_BEFORE_RECV and O_PATH addfdKees Cook1-0/+8
Describe SECCOMP_FILTER_FLAG_RESTART_BEFORE_RECV in the UAPI header, as SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV is described above it, and say in the documentation that supervisors must tolerate ENOENT from SECCOMP_IOCTL_NOTIF_RECV, which the flag makes routine. Note at the fget_raw() call that O_PATH files are allowed on purpose. Build tested ARCH=x86_64 defconfig (kernel/seccomp.o and headers) with GCC 16.2.0, and SPHINXDIRS=userspace-api htmldocs. Assisted-by: LLM Signed-off-by: Kees Cook <kees@kernel.org>
2026-10-06docs/seccomp: describe the SECCOMP_FILTER_FLAG_RESTART_BEFORE_RECV flagCong Wang1-0/+29
Document the new opt-in flag, its listener requirement and interaction with WAIT_KILLABLE_RECV. Explain syscall re-evaluation and the cancellation, timeout, fairness and argument-mutation tradeoffs. Assisted-by: Codex:gpt-6 Signed-off-by: Cong Wang <cwang@multikernel.io> Link: https://patch.msgid.link/20260924204209.477694-4-xiyou.wangcong@gmail.com Signed-off-by: Kees Cook <kees@kernel.org>
2026-10-05media: mc: Add INTERNAL pad flagSakari Ailus1-0/+9
Internal sink pads will be used as routing endpoints in V4L2 [GS]_ROUTING IOCTLs, to indicate that the stream begins in the entity. Internal sink pads are pads that have both SINK and INTERNAL flags set. Also prevent creating links to pads that have been flagged as internal and initialising SOURCE pads with INTERNAL flag set. Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Tested-by: Martin Hecht <mhecht73@gmail.com> Reviewed-by: Mirela Rabulea <mirela.rabulea@nxp.com> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
2026-09-15docs: ioctl: fix stale NVMe registry entry and note N conflictIván Ezequiel Rodriguez1-2/+3
The NVMe row pointed at drivers/block/nvme.c, which no longer exists, and ioctl numbers 0x80-0x83 overlap between ntsync.h and nvme_ioctl.h without a conflict! marker. Signed-off-by: Iván Ezequiel Rodriguez <ivanrwcm25@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260831143125.151360-7-ivanrwcm25@gmail.com>
2026-09-15docs: vduse: align documentation with current uapi and driverIván Ezequiel Rodriguez1-12/+21
Update supported device IDs (block, net, fs), all six read/write message types, the VDUSE_VQ_INJECT_IRQ ioctl name, and VQ_SETUP group vs asid usage per include/uapi/linux/vduse.h. Signed-off-by: Iván Ezequiel Rodriguez <ivanrwcm25@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260831143125.151360-6-ivanrwcm25@gmail.com>
2026-09-15docs: dma-buf-heaps: fix CMA heap name typoIván Ezequiel Rodriguez1-1/+1
Line 39 used default-cma-region with hyphens; the registered heap name is default_cma_region, already named correctly at line 26. Signed-off-by: Iván Ezequiel Rodriguez <ivanrwcm25@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260831143125.151360-5-ivanrwcm25@gmail.com>
2026-09-15docs: futex2: fix documented errno names for futex_waitvIván Ezequiel Rodriguez1-2/+2
The documentation cited -EAGAIN and -ETIMEOUT, but futex_waitv() returns -EWOULDBLOCK on value mismatch and -ETIMEDOUT when the timeout expires, per kernel/futex/waitwake.c. Signed-off-by: Iván Ezequiel Rodriguez <ivanrwcm25@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260831143125.151360-2-ivanrwcm25@gmail.com>
2026-09-09media: uapi: Add controls for ST DCMIPP DriverAlain Volmat2-0/+15
Add definitions and documentation for the custom control provided by the DCMIPP driver in order to control the pixelproc gamma correction. Signed-off-by: Alain Volmat <alain.volmat@foss.st.com> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
2026-09-07Documentation: userspace-api: iommufd: Fix the struct iommu_hwpt_alloc nameKarl Mehltretter1-1/+1
struct iommufd_hwpt_alloc does not exist; the name is struct iommu_hwpt_alloc. Use struct iommu_hwpt_alloc. Fixes: e2d8fe9148b7 ("Documentation: userspace-api: iommufd: Update HWPT_PAGING and HWPT_NESTED") Assisted-by: LLM Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260905103819.43424-1-kmehltretter@gmail.com>
2026-09-07docs: ioctl-number: Point the 0xEC row at cros_ec_chardev.hKarl Mehltretter1-1/+1
The 0xEC entry points at drivers/platform/chrome/cros_ec_dev.h, which commit 5e0115581bbc ("cros_ec: Move cros_ec_dev module to drivers/mfd") moved; the ioctl numbers now live in include/linux/platform_data/cros_ec_chardev.h. Point the row at that file. Fixes: eda2e30c6684 ("mfd / platform: cros_ec: Miscellaneous character device to talk with the EC") Assisted-by: LLM Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260905102754.43160-1-kmehltretter@gmail.com>
2026-08-27Merge tag 'mm-stable-2026-08-26-15-22' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff" (Lorenzo Stoakes) Index MAP_PRIVATE file-backed folios by their anonymous page offset to resolve confusion around reverse mapping for zeroed and CoW'd file-backed memory. Use this new VMA anonymous page offset tracking to eliminate index conflicts and lay the foundation for scalable CoW performance improvements. - "promote mapped executable folios after first usage for MGLRU" (Baolin Wang) Make MGLRU's protection of mapped executable file folios more reliable. Follow the classical LRU's logic, promoting mapped executable file folios after their first usage to give executable code a better chance to stay in memory and improve workload performance. - "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong Chen) Fix per-node proactive reclaim interface's ignoring the swappiness parameter when CONFIG_MEMCG is disabled by consolidating sc_swappiness() into a single function that checks proactive_swappiness regardless of kernel configuration. - "mm/vmscan: reduce lru_lock contention via vmstat-derived scan-balance cost" (Usama Arif) Reduce lru_lock contention in the reclaim path by deriving scan-balance costs from vmstat counters rather than lock-acquired producer updates. Read and decay these cost signals on the reclaim side under a dedicated per-lruvec lock, reducing total LRU lock wait time by over 60% without impacting scan throughput. - "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky) Fix two low-risk zram bugs which Sashiko spotted in drive-by review. - "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's memcg" (Zi Yan) Fix xas_split_alloc() by enabling target folio memcg charging during splits and adding the missing __GFP_ACCOUNT flag for proper XArray node memory accounting. - "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick) Replace hardcoded binary names in selftests/mm/.gitignore with a generic pattern-matching rule to automatically ignore generated test files and avoid manual updates when adding new tests. - "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon) Make the incompatibility between FLATMEM and NUMA explicit in mm/Kconfig and remove the unused pgdat_page_ext_init() function. - "zram: fix zstd error paths and add parameter validation" (Haoqin Huang) Clean up zram compression backends by removing redundant error cleanup, adding parameter and dictionary validation, auto-prefixing algorithm error logs, and resetting parameters prior to reinitialization. - "zram: fix stale scan bounds after reinitialization" (Longlong Xia) Prevent out-of-bounds slot accesses during concurrent zram resets by moving table scan bound calculations under dev_lock in writeback_store() and read_block_state(). - "add anon mTHP collapse test cases" (Baolin Wang) Extend selftests helper functions to support arbitrary page orders and add new test cases and options for mTHP collapse in khugepaged. - "selftests/mm: Handle unsupported and transient test conditions" (Muhammad Usama Anjum) Update MM selftests to report a SKIP status instead of a failure when required kernel or filesystem features are unsupported, while adding retry logic for transient page migration errors. - "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia) Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled and extend shrink_memcg() to support batch writeback for improved writeback efficiency. - "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren Baghdasaryan) Introduce an IOCTL-based binary interface for memory allocation profiling that enables kernel-side filtering before per-CPU counter aggregation. This eliminates the text-parsing overhead of /proc/allocinfo and provides up to a 20x speedup by transferring only filtered allocation data to userspace. - "better block swap batching and a different take on swap_ops v5" (Christoph Hellwig) Refactor block swap I/O to use swap_iocb for batching instead of single-bio requests and rebase the swap_ops interface, achieving faster swap throughput during kernel builds. - "mm: kmemleak: reduce transient false positives by confirming leaks" (Catalin Marinas) Reduce false-positive kmemleak reports by combining two kmemleak enhancements that add a second confirmation scan and a configurable minimum unreferenced scan count module parameter. - "mm: kmemleak: default min_unref_scans to 2 for verbose kernels" (Breno Leitao) Auto-scanning kernels can generate false-positive memory leak reports on single scans, so this patch defaults min_unref_scans to 2 when CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second confirming scan. - "swap_ops updates" (Christoph Hellwig) Batching I/O for synchronous swap devices causes performance regressions and filesystem-based swap suffers from double-indirection overhead. This series resolves both issues by reintroducing per-folio writes for synchronous swap and allowing filesystems to directly export their own swap_ops. - "mm/khugepaged: several cleanups" (Nico Pache) khugepaged accumulated redundant state-checking patterns and outdated comments following mTHP integration. Introduce dedicated helpers for PTE validation and event counting while refreshing the internal documentation. - "maple_tree: lock checking and clean ups" (Liam Howlett) Syzbot reports incorrectly blame memory management exit paths for locking bugs, maple tree erase operations risk allocation failures without gfp flags and internal documentation lacks clarity. Improve lock error detection, update docs, fix race and allocation edge cases and optimize erase allocations using a fallback to GFP_KERNEL | GFP_NOFAIL. * tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (172 commits) selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC memcg: move LRU size accounting on reparenting instead of copying it mm/vmscan: fix comment logic in balance_pgdat maple_tree: add helper mas_make_walkable() maple_tree: avoid extra gap calculation maple_tree: fix argument name in header maple_tree: change two GFP flags in tests maple_tree: document erase and allocations better maple_tree: avoid mas_erase() and mtree_erase() failures maple_tree: document that erase may use GFP_KERNEL for allocations maple_tree: catch race in mas_alloc_cyclic() maple_tree: add bulk parent set helper maple_tree: micro optimisation of mas_wr_store_type() maple_tree: optimise mas_wr_node_store() when not in rcu mode maple_tree: use prefetched value in mas_wr_store_type() maple_tree: clarify comments on mas_nomem() maple_tree: drop MAPLE_ALLOC_SLOTS maple_tree: drop dead code from mas_extend_spanning_null() maple_tree: documentation fix maple_tree: add write lock checking with lockdep sequence numbers ...
2026-08-25Merge tag 'char-misc-7.3-rc1' of ↵Linus Torvalds1-16/+17
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc/IIO/etc driver updates from Greg KH: "Here is the big set of char, misc, iio, counter, fpga, and other small driver subsystems for 7.3-rc1. Overall, due to some driver removals we only added a bit more code than removed, which was a nice change. Highlights in this merge request are: - Loads of IIO driver updates and additions - binder driver updates (more on that below...) - Removal of the SGI XP and GRU drivers as they are not used anymore and turn out to be pretty insecure overall - Removal of the obsolete ibmasm driver as it's not being used anymore - Coresight driver updates and additions - Mei driver udpates - Counter driver updates - FPGA driver updates - ICC driver updates - lots and lots of other tiny driver updates to resolve reported issues All of these have been in linux-next for a while" * tag 'char-misc-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (513 commits) iio: chemical: atlas-sensor: use iio_trigger_poll_nested() to fix remove UAF iio: adc: pac1921: fix wrong channel used in trigger handler read iio: light: gp2ap002: re-enable irq if runtime suspend fails iio: light: gp2ap002: Fix unbalanced runtime PM on repeated event writes iio: light: apds9306: fix PM reference leak in apds9306_read_data() iio: gyro: mpu3050: fix sign of raw angular velocity readings iio: srf04: fix pm_runtime handling on probe error path iio: adc: ad4080: configure backend data size iio: adc: adi-axi-adc: add data size support for AD408X backend iio: chemical: atlas-sensor: fix PM reference leak in buffer postenable iio: dac: ad5446: fix OF module device table iio: light: opt4001: Fix reversed GENMASK() arguments in fault count mask iio: light: opt4001: Reject integration times with a non-zero seconds part iio: light: opt4001: Fix incompatible pointer type passed to div_u64_rem() iio: light: opt4001: Fix power down clearing bits of the wrong register iio: light: opt4060: Fix incorrect register name in threshold read error message iio: light: opt4060: Fix pointer type passed to div_u64_rem() iio: light: opt4060: Reject integration times with a non-zero seconds part iio: light: ltrf216a: fix runtime PM reference leak in error path iio: pressure: dps310: fix NULL pointer dereference on ACPI probe ...
2026-08-24alloc_tag: add ioctl to /proc/allocinfoSuren Baghdasaryan1-0/+2
Patch series "alloc_tag: introduce IOCTL-based filtering for MAP", v8. Currently, memory allocation profiling data is primarily exposed through /proc/allocinfo. While useful for manual inspection, this text-based interface poses challenges for production monitoring and large-scale analysis: 1. Userspace must parse large amounts of text to extract specific fields. 2. To find specific tags, userspace must read the entire dataset, requiring many context switches and high data copying. 3. The kernel currently aggregates per-CPU counters for every allocation size, even those the user intends to filter out immediately. This series introduces a new IOCTL-based binary interface for allocinfo that supports kernel-side filtering. By allowing the user to specify a filter mask, we significantly reduce the work performed in-kernel and the amount of data transferred to userspace. The IOCTL mechanism was chosen for allocinfo to address the per-CPU counter aggregation bottleneck. A traditional read() operation must report the total allocation count and sizes for every code tag in the system. Doing so requires iterating across all CPUs to sum their per-CPU counters for thousands of tags, which introduces substantial runtime overhead. The IOCTL interface allows userspace to push selective filtering criteria directly into the kernel before the per-CPU counter aggregation. The kernel aggregates per-CPU counters only for a small subset of tags that match the filter. This results in significant performance improvement. Beyond fast filtered retrieval, the IOCTL foundation allows introducing a context capture mechanism in the future to capture the context for specific allocations. Performance measurements were conducted on an Intel Xeon Platinum 8481C (224 CPUs) with caches dropped before each run. The IOCTL mechanism shows a ~20x performance improvement for filtered queries. The kernel avoids the expensive per-CPU counter aggregation (alloc_tag_read) for any tags that fail the initial string or location filters. Scenario 1: Specific File Filtering (arch/x86/events/rapl.c) 1. Traditional (cat /proc/allocinfo | grep): 22ms (sys) 2. IOCTL Interface: 1ms (sys) Scenario 2: Compound Filtering (Filename + Size) 1. Traditional: (cat ... | grep | awk): 21ms (sys) 2. IOCTL Interface: 1ms (sys) Scenario 3: Size-Based Filtering (min_size = 1MB) 1. Traditional: (cat ... | awk): 21ms (sys) 2. IOCTL Interface: 14ms (sys) This patch (of 6): Add the following ioctl commands for /proc/allocinfo file: ALLOCINFO_IOC_CONTENT_ID - gets content identifier which can be used to check whether the file content has changed specifically due to module load/unload. Every time a module is loaded / unloaded, the returned value will be different. By comparing the identifier value at the beginning and at the end of the content retrieval operation, users can validate retrieved information for consistency. ALLOCINFO_IOC_GET_AT - gets the record at the specified position. This is the position of a record in /proc/allocinfo. ALLOCINFO_IOC_GET_NEXT - gets the record next to the last retrieved one. If no records were previously retrieved, returns the first record. Note, function file and module names often have the same prefixes, therefore when filtering for them, we compare the last 64 characters to minimize the chances of name collisions. [akpm@linux-foundation.org: include compat.h, per Suren] Closes: https://lore.kernel.org/oe-kbuild-all/202607091820.qbjlGhKK-lkp@intel.com/ Link: https://lore.kernel.org/cover.1783532853.git.abhishekbapat@google.com Link: https://lore.kernel.org/15596de2607ef13e7c77c6d74763f4ae992ec475.1783532853.git.abhishekbapat@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Abhishek Bapat <abhishekbapat@google.com> Acked-by: Hao Ge <hao.ge@linux.dev> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Sourav Panda <souravpanda@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-21Merge tag 'landlock-7.3-rc1' of ↵Linus Torvalds1-8/+54
git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux Pull Landlock update from Mickaël Salaün: "This improves observability with Landlock tracepoints support, which required some refactoring for dedicated domain types and common helpers shared with audit code. A LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS flag is also added to improve process-wide domain enforcement consistency. Whiteout files are now correctly handled and tested, and a few other fixes" * tag 'landlock-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux: (34 commits) landlock: Document tracepoints selftests/landlock: Add landlock_enforce_domain trace tests selftests/landlock: Add scope and ptrace tracepoint tests selftests/landlock: Add network tracepoint tests selftests/landlock: Add filesystem tracepoint tests selftests/landlock: Add trace event test infrastructure and tests landlock: Add tracepoints for ptrace and scope denials landlock: Add landlock_deny_access_fs and landlock_deny_access_net landlock: Add tracepoints for rule checking landlock: Add landlock_enforce_domain tracepoint landlock: Add create_domain and free_domain tracepoints landlock: Add landlock_add_rule_fs and landlock_add_rule_net tracepoints landlock: Add create_ruleset and free_ruleset tracepoints landlock: Consolidate access-right and scope names in a shared header landlock: Decouple the per-denial logging decision from CONFIG_AUDIT landlock: Split denial logging from audit into common framework landlock: Split struct landlock_domain from struct landlock_ruleset landlock: Move domain query functions to domain.c landlock: Prepare ruleset and domain type split samples/landlock: Add LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS to sampler ...
2026-08-20Merge tag 'mm-stable-2026-08-18-18-39' of ↵Linus Torvalds1-8/+6
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "mm: drop "sub" prefix from various places" (Dev Jain) page->folio conversion and a naming cleanup - "mm/kasan: remove redundant initialization for kasan_flag_write_only" (Igor Putko) KASAN cleanup work - "mm/filemap: reduce unnecessary xarray lookups" (Chi Zhiling) Small speedup in the pagecaache read code - "mm/percpu: Fix possible NOFS/NOIO reclaim recursion" (Kaitao Cheng) Improve the vmalloc code - mainly the avoidance of GFP_KERNEL allocations when the caller asked for GFP_NOFS or GFP_NOIO - "mm/kmemleak: avoid soft lockup when scanning task stacks" (Breno Leitao) Avoid a soft lockup watchdog trigger from the kmemleak scanning code in extreme situations - "mm/page_owner: misc cleanups" (Ye Liu) Cleanups to the page_owner code. For some reason lots of people have been working on the page_owner code this cycle. - "mm: convert to walk_page_range_vma() to eliminate find_vma()" (Kefeng Wang) Simplify and accelerate the page walking library function - "mm/migrate: preparatory cleanups for batch copy and offload" (Shivank Garg) Cleanups in the migration code - "mm/page_owner: add per-fd filter infrastructure for print_mode and NUMA filtering" (Zhen Ni) Per-fd filtering to page_owner in order to reduce the sometimes vast amount of output it can produce - "mm: Refactor bootmem gigantic hugepage allocation" (Muchun Song) Fixes and preparatory cleanups around bootmem HugeTLB handling, sparse initialization ordering, and related vmemmap setup - "mm/zsmalloc: reduce lock contention in zs_free()" (Wenchao Hao) Reduce lock contention in zs_free(), which dominates the unmap path under memory pressure on Android (LMK kills) and on x86 servers running zswap-heavy workloads. Up to 1.83x improvement in microbenchmarking. - "move alloc_tag.c file under mm/" (Suren Baghdasaryan) - "samples/damon: handle damon_{start,stop}() failures" (SJ Park) Fix improper handling of damon_start(), damon_stop(), and damon_call() failures across DAMON sample modules to prevent potential memory leaks, operation disruptions and use-after-free bugs - "mm/damon/sysfs: kobject_del() directories that users can create/remove" (SJ Park) Fix delayed sysfs directory removal under DEBUG_KOBJECT_RELEASE causeing creation failures due to duplicate directory names by adding missing kobject_del() calls before creating new directories - "mm: cleanup clear_not_present_full_ptes()" (David Hildenbrand) Clean up the core pte handling code - "selftests/damon: misc fixes for test bugs" (Kunwu Chan) Fix several bugs in the DAMON selftests - "selftests/damon: fix memcg_path staging handling" (Cheng Nie) Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and add a test case for it in sysfs.py. - "selftests/damon: test kdamond refresh_ms" (Ruslan Valiyev) Selftest coverage for DAMON's refresh_ms sysfs feature by updating the test control module and verifying that scheme stats update automatically without manual intervention - "mm/damon: five misc fixups" (Akinobu Mita) Miscellaneous DAMON fixups. - "mm/damon/core: detect internal variation above max_nr_regions/2" (Jiayuan Chen) Fix DAMON's region splitting behavior when region counts exceed half the maximum budget by dynamically scaling down the split fraction as the limit approaches, preventing large regions from staying un-split, and add corresponding KUnit test coverage - "mm: preparatory patches for PMD level swap entries" (Usama Arif) Refactor and clean up PMD softleaf helpers, call sites, and architecture flags to lay the groundwork for a follow-up series that introduces PMD page table swap entries - "mm/damon: update, optimize, and clean up doc, tests, and code" (SJ Park) Update DAMON design and ABI documentation, expands unit and selftest coverage, optimize damon_commit_target_regions(), and clean up recently added sysfs interface code for better readability - "mm/vmpressure: reduce CPU, memory and code overhead on cgroup v2" (Usama Arif) Optimize vmpressure() by skipping unnecessary work on cgroup v2 for userspace event notifications and refactor v1-only eventfd handling into mm/memcontrol-v1.c to reduce memory overhead and code complexity - "selftests/mm: refactor pkey helpers and fix mmap error handling" (Hongfu Li) Refactor pkeys shared tracing and assertion helpers into a common file, unify protection key selftests to use consistent diagnostic logging and assertions, and enforce standardized MAP_FAILED return checks for mmap() calls across the tests - "mm/damon: optimize out nr_accesses_bp" (SJ Park) Replace the error-prone, continuously updated nr_accesses_bp field in damon_region with an on-demand moving sum function, reducing structure memory overhead and avoiding state corruption bugs - "Open HugeTLB allocation routine for more generic use" (Ackerley Tng) Decouple HugeTLB folio allocation from VMA dependencies by introducing hugetlb_alloc_folio(), enabling subsystems like guest_memfd to allocate HugeTLB folios without standard VMA reservations or pseudo-VMAs - "mm/damon: provide pseudo moving sum probe_hits" (SJ Park) Integrate DAMON's probe_hits attribute counter into the pseudo moving sum infrastructure, enabling real-time, online monitoring without waiting for full aggregation intervals - "mm: Some cleanups for page allocator APIs" (Brendan Jackman) Simplify and refactor the page allocator entry points and flags by unifying allocation paths, adding internal alloc_flags arguments, and eliminating redundant __ prefixed alloc_pages variants. - "Fix incorrect access of hugetlb pte entries" (Dev Jain) Enforce the consistent use of huge_ptep_get() instead of ptep_get() for HugeTLB entries and fixes an unaligned address issue in arm64's huge_ptep_get() implementation - "mm/damon: validate all parameters in the core" (SJ Park) Consolidate parameter validation into the DAMON core specifically within damon_start() and damon_commit_ctx() to centralize error checking, eliminate caller-side redundant checks and to improve maintenance efficiency - "tools/mm/page_owner_sort: fix filtering and cleanup issues" (Yichong Chen) Rename is_need() to filter_record() for clearer return semantics, fix per-record allocation memory leaks and bound output copies in search_pattern() to address an existing buffer issue - "memcg: bail out reclaim when memcg is dying" (Jiayuan Chen) Mitigate a system-wide stall which occurs when a cgroup is removed while one of its memory control files is doing synchronous reclaim - "mm/memory-failure: add panic option for unrecoverable pages" (Breno Leitao) Introduce an opt-in vm.panic_on_unrecoverable_memory_failure sysctl that immediately panics the kernel on unrecoverable memory errors in kernel-owned pages to preserve error context and prevent delayed, silent data corruption - "mm/damon: refactor damon_{start,stop,commit}() for simple error handling" (SJ Park) Refactor the DAMON core API functions to guarantee that all contexts are fully stopped when damon_start(), damon_stop(), or damon_commit() fail, eliminating the need for complex and error-prone caller-side cleanup code - "Keep tail page private zero at free and folio split" (Zi Yan) Add checks to ensure tail_page->private is zero when freeing compound or high-order pages and when promoting tail pages during large folio splits. By validating these fields at free and split time, it allows the removal of redundant private field clearing inside prep_compound_tail() - "mm: drop redundant lru_add_drain in anon folio reuse paths" (Barry Song) Eliminate redundant lru_add_drain() calls in wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock contention and system overhead By validating folio refcounts against the LRU cache before draining and removing unnecessary drains in the swap path, it achieves up to a 30.5% reduction in drain calls during heavy swap workloads - "mm: clean up folio LRU and swap declarations" (Jianyue Wu) Reorganize folio LRU and swap code by relocating page-cluster state to mm/swap_state.c, renaming mm/swap.c to mm/folio.c, and moving MM-internal reclaim declarations into mm/internal.h. - "userfaultfd: working set tracking for VM guest memory" (Kiryl Shutsemau) Add userfaultfd support for tracking the working set of VM guest memory, so a VMM can identify hot pages and reclaim cold ones to tiered or remote storage - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 2)" (David Hildenbrand) Remove the remaining pieces of CONFIG_HAVE_BOOTMEM_INFO_NODE, performing some smaller cleanups around freeing of reserved vmemmap pages on the way. - "mm/damon: update probe hits for runtime parameter commits" (SJ Park) Ensure that DAMON's probe_hits attribute counter is properly updated when monitoring intervals are changed at runtime, matching the behavior of nr_accesses. To achieve this, it refactors and renames existing helper functions for shared use, applies the updates to probe_hits, and handles edge cases in damon_probe_hits_mvsum() to maintain measurement accuracy. - "KSM: performance optimizations for rmap_walk_ksm" (xu xin) Resolve a severe KSM reverse-mapping performance bottleneck where thousands of split VMAs sharing a single anon_vma cause extended lock contention. By adding an interval-filtering check during the rmap walk, it reduces worst-case anon_vma lock hold times from over 500ms down to under 2ms, preventing application freezes and latency spikes under memory pressure. - "mm: split a couple of headers from internal.h" (Mike Rapoport) Split declarations related to mm_init, memblock, vmalloc and sparse into new headers - "KSM: use linear_page_index in collect_procs_ksm()" (xu xin) Apply the interval tree optimization from rmap_walk_ksm() to collect_procs_ksm() to avoid iterating over non-matching VMAs during KSM memory error handling. It hoists loop-invariant address initialization and restricts the anon_vma_interval_tree_foreach walk to a targeted page offset range, reducing redundant checks and improving lookup efficiency. - "selftests/mm: avoid false failures in hugetlb and KSM tests" (Sayali Patil) Fix issues in the hugetlb and KSM MM selftest categories that can report failures when the prerequisites for the tests are not satisfied - "mm/damon: introduce data attributes only monitoring" (SJ Park) Introduce attribute-weighted region management in DAMON, allowing users to prioritize specific data attributes (such as page sizes or cgroups) over or instead of access monitoring. By assigning weights to attribute probes, DAMON can completely disable access tracking and adjust monitoring regions based on weighted probe-hit counters to optimize monitoring quality for attribute-focused workloads. - "mm/hmm: Add mmap lock-drop support for userfaultfd-backed mappings" (Stanislav Kinsburskii) Extend hmm_range_fault() to support userfaultfd-backed regions by allowing the mmap lock to be dropped during fault handling via a new hmm_range_fault_locked() helper. By accepting a locked pointer and signaling retry status when lock release occurs, it enables page fault resolution in userfaultfd regions while preserving backward compatibility for existing callers. - "mm: make VMA page offset handling more consistent" (Lorenzo Stoakes) Clean up and standardize how vma->vm_pgoff is accessed and manipulated across file-backed and anonymous mappings in the kernel It introduces dedicated helper functions such as vma_start_pgoff(), vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while renaming rmap interval tree helpers to better reflect their functionality. These changes establish a cleaner foundation for future work that will unify virtual page offset indexing for all anonymous and CoW'd folios. - "mm: handle device-private PMDs in walk callbacks" (Usama Arif) Address kernel panics and state corruption caused by MM walk callbacks reaching non-present device-private PMD swap entries created during HMM migrations It ensures that functions which acquire pmd_trans_huge_lock() properly recognize device-private PMDs instead of assuming a present THP or a standard migration entry. - "mm/rmap: Refactor try_to_unmap_one" (Dev Jain) Refactor try_to_unmap_one by modularizing Hugetlb, anonymous-lazyfree, and anonymous-swapbacked logic into dedicated functions, laying the structural groundwork for batched anonymous large folio unmapping. - "Docs/ABI/damon: sysfs ABI document fixes and additions" (Song Hu) Fix typos and fills in missing entries in the DAMON sysfs ABI document - "dax/kmem: atomic whole-device hotplug via sysfs" (Gregory Price) Introduce an atomic sysfs state attribute and supporting DAX/MM infrastructure to prevent userland races when offlining and removing entire memory regions By adding an unplugged state alongside standard online modes, it enables whole-device atomic hotplug control while preserving backward compatibility. - "mm: convert more vm_flags_t users to vma_flags_t" (Lorenzo Stoakes) Continue transitioning the kernel from the deprecated vm_flags_t type to vma_flags_t across core memory management infrastructure. It replaces legacy type usage in core functions such as do_mmap(), unmapped area allocation, mm->def_vma_flags, and VMA operations like mlock, mprotect, and mremap. - "Two small patches to clean up mm/mm_slot.h" (xu xin) Refactor mm_slot.h by introducing mm_slot_remove() to unify duplicate slot deletion sequences in khugepaged and KSM. It also adds code documentation explaining why mm_slot_lookup and mm_slot_insert must remain as preprocessor macros rather than static inline functions. - "mm/damon/core: hide core-private struct fields" (SJ Park) Clean up DAMON core structures by consistently marking internal-only fields with private: comment tags to prevent improper direct access from outer layers. It enforces encapsulation across core structures including damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to interact through approved access APIs instead of exposing raw struct members. - "mm/damon: unurgent fixes for infinite loop, NULL de-ref and races" (SJ Park) Address potential infinite loops, NULL dereferences, and race conditions identified in DAMON It fixes an infinite loop triggered by extreme user configurations, a NULL pointer dereference within unit tests and minor monitoring accuracy degradation caused by subtle runtime races. - "mm/page_alloc: fixes for free_pages_nolock() on RT/UP" (Brendan Jackman) Fix an NMI safety flaw in __free_frozen_pages() where freeing pages on non-SMP or PREEMPT_RT kernels can bypass can_spin_trylock() checks via non-PCP or isolated migration paths. It also resolves potential kernel crashes and privilege escalation risks triggered when BPF tracing runs in NMI context alongside memory hotplug or large allocation frees. - "mm/page_alloc: couple of followups for recent cleanups" (Brendan Jackman) Clean up and update page allocator nomenclature, documentation, and debug assertions. It aligns internal FPI_ flags with the public "nolock" naming convention, removes outdated internal implementation details from high-level page allocator comments, and eliminates obsolete VM_BUG_ON() assertions in allocation paths. - "mm/mseal: further cleanups" (Lorenzo Stoakes) Refactor and simplify the mseal implementation by clarifying API boundaries and removing unnecessary code complexity. It replaces generic do_mseal() usage outside the syscall with a dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO, eliminates mm_struct parameters to enforce that sealing applies only to current->mm, and streamlines overall logic and comments with no functional changes intended. - "mm/vmscan: fix swappiness=max and clean up per-node proactive reclaim" (Ridong Chen) Resolve reclaim behavior bugs and clean up function parameters across memory reclaim paths It fixes swappiness=max in both standard reclaim and MGLRU so unswappable anonymous memory no longer falls back to evicting page cache, ensures reclaim_store() returns accurate error codes instead of collapsing all failures into -EAGAIN, and removes the obsolete gfp_mask parameter from __node_reclaim(). - "mm: mincore: misc cleanups" (Kefeng Wang) Clean up and simplifies the mincore code. Most importantly, it removes the historical special behavior that always