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51 min.Merge tag 'ntfs3_for_7.4' of ↵Linus Torvalds
https://github.com/Paragon-Software-Group/linux-ntfs3 Pull ntfs3 updates from Konstantin Komarov: "The bulk of this cycle is hardening against corrupted or maliciously crafted volumes. Most of these fixes come from fuzzing and KASAN reports. The main areas are: - $LogFile replay, where several unchecked on-disk sizes could make mount write past the MFT record buffer - MFT record and index parsing - extended attributes, where a bad $EA entry could leak up to 64K of kernel heap to userspace through getxattr() Reading a damaged compressed file could also return uninitialized page cache contents to userspace; that is fixed too. A few fixes affect healthy volumes as well: a heap overflow in fallocate(INSERT_RANGE) on small files, a use-after-free when a WOF-compressed file is opened for writing during a concurrent read, a lock-order deadlock in readdir, and stale disk data showing up in newly allocated clusters of compressed files. On the feature side there are new tracepoints covering mount, log replay, lookup, directory index, allocation, iomap and file I/O. There is also a new 'ugm' mount option (on by default): with ugm=0, newly created files don't get the WSL uid/gid/mode extended attributes, which Windows doesn't use. The rest is smaller correctness fixes and cleanups" * tag 'ntfs3_for_7.4' of https://github.com/Paragon-Software-Group/linux-ntfs3: (52 commits) ntfs3: add file I/O tracepoints ntfs3: add iomap tracepoints ntfs3: add allocation tracepoints ntfs3: add directory index tracepoints ntfs3: add create inode tracepoint ntfs3: add namei tracepoints ntfs3: add mount and log replay tracepoints fs/ntfs3: validate the EA value length in ntfs_read_ea() fs/ntfs3: handle partial allocation in attr_data_get_block_locked() ntfs3: fix mapping pairs bounds check for alignment fs/ntfs3: bound DeleteAttribute asize against rec->used in do_action ntfs3: release ni_lock before dir_emit in ntfs_readdir to fix deadlocks fs/ntfs3: bound CreateAttribute asize against record_size in do_action fs/ntfs3: do not mark frame pages uptodate on read error fs/ntfs3: prevent positive E_NTFS_NONRESIDENT from reaching writeback error handling fs/ntfs3: fix ntfs_fnd leak when compare function is missing fs/ntfs3: fix stale attr_b in attr_allocate_frame() fs/ntfs3: reject unaligned hole punching on compressed files fs/ntfs3: take ni_lock() once in ntfs_readdir() fs/ntfs3: reserve a compression unit in maxbytes_sparse ...
2 daysMerge tag 'mm-stable-2026-10-25-19-27' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "mm: make VMA flag semantics explicit, eliminate VM_SPECIAL" (Lorenzo Stoakes): Replace VM_SPECIAL with helpers describing mapping ownership and behavior. Enforce the mmap flag rules and convert affected drivers, removing ambiguous tests shared by driver mappings and ordinary memory. - "support kselftest on nommu platform" (Hajime Tazaki): Add opt-in mmap and mremap tests for NOMMU systems. Teach the runner to avoid its fork-dependent timeout command and document the build and runtime requirements. - "mm/collapse: separate a collapse from its callers" (Kiryl Shutsemau): Separate huge-page collapse from caller policy. Replace khugepaged identity checks with explicit permissions, and separate scanning from collapse with the mmap_lock drop in one place. - "mm: implement and use vma_has_anon_rmap(), silence KCSAN" (Lorenzo Stoakes): Provide a common helper for testing whether a VMA has anonymous reverse mappings. Document the locking rules, annotate intentional concurrent reads for KCSAN, and convert the core MM callers. - "mm/sparse: remove SECTION_MARKED_PRESENT and further cleanups" (David Hildenbrand): Remove SECTION_MARKED_PRESENT in favor of the early-section flag. Simplify sparse memory initialization, section metadata handling and related PFN validity checks. - "sh: remove NUMA and SPARSEMEM support" (Mike Rapoport): Remove SuperH NUMA and SPARSEMEM support. The extra memory banks have been unusable since the NO_BOOTMEM conversion, leaving only the code and data overhead. - "mm: Unify device DAX and HugeTLB vmemmap population paths" (Muchun Song): Unify the generic device DAX and HugeTLB vmemmap population paths and shared tail-page handling. Remove the duplicate DAX machinery while retaining the powerpc radix implementation. - "kselftest: mm: fix some failure of split_huge_page_test" (Yeoreum Yun): Fix huge-page split tests racing with khugepaged recollapse. Use pagemap and page flags instead of VMA-boundary assumptions which fail when glibc has already enabled THP. - "memcg: move memcgid refcount to objcg to unpin dying memcgs" (Bingfang Guo): Let dying memcgs be freed while swapped-out shmem still holds their IDs. Move ID references to reparentable objcgs, with the necessary swap accounting and RCU lifetime changes. - "mm/truncate: fix data loss when truncating straddling large folios" (Zhang Yi): Preserve out-of-range data when truncating straddling large folios. Fix a lookup race and split-failure handling, and handle minimum folio orders for the forthcoming ext4 iomap buffered I/O path. - "mm/damon: introduce damos quota goal target metric complement flag" (SJ Park): Let DAMOS quota goals use a metric's complement, so utilization can also express free-memory goals without adding separate metrics. Add the sysfs interface, documentation and tests. - "arm64/mm: Standardize printing for pgtable entries" (Anshuman Khandual): Use the generic formatter for arm64 page-table entries, ready for future wider entries. Move the safe-PTE-update check out of the header to avoid an include cycle. - "mm: kmsan: fix iounmap metadata teardown" (Dima Koziuk): Fix KMSAN metadata leaks on iounmap and failed ioremap allocations. Free backing pages before removing their mappings, and share the teardown with partial-allocation cleanup. - "mm/damon/core: preserve quota state when constructing schemes" (Karl Mehltretter): Preserve running DAMOS quota state while validating parameter updates. Even rejected updates could reset accounting and exceed the quota window; add tests for both accepted and rejected updates. - "mm/vmalloc: fix vmalloc_dump_obj VA lookup" (Ye Liu): Fix vmalloc_dump_obj() lookups for last-page addresses and allocations spanning vmap zones. These allocations were being missed in diagnostic output. - "mm: various (urgent?) fixes" (David Hildenbrand): Fix mmap charge leaks and hugetlb use-after-free, wrong-address unmapping, stuck locks and endless faults. Also preserve reservations on failed mremap and handle stale userfaultfd bits. - "maple_tree: fix maple_range_64 crashes in RCU mode" (Dimitris Charisis): Fix pointer and metadata confusion during RCU destruction of maple_range_64 nodes, avoiding double frees and invalid accesses. Add a regression test; no in-tree user currently uses this combination. - "mm: fix hugetlb NR_HUGETLB accounting on folio migration" (Hongfu Li): Fix hugetlb migration and preallocation accounting so /proc/vmstat retains the correct count and memory.numa_stat follows the folio to its new node. - "mm/damon: fix a minor bug, clean code, and add a test" (SJ Park): Fix 32-bit DAMON age overflow which made old regions look young. Share hugetlb folio acquisition code and add a regression test for the previously fixed last-region skipping bug. - "mm/damon/core: cleanup code, reduce stack usage, and add kunit" (SJ Park): Reduce kdamond stack usage and remove unused enums. Add deterministic PSI quota-goal tests which do not depend on the machine's current memory pressure. - "mm/damon: fix the temporal goal tuner's size quota conversion" (Donggeun Yoo): Bound the temporal tuner's quota conversion to prevent overflow and zero effective quotas, which could stop schemes making progress. Add boundary tests. - "Don't use GFP_DMA when calling dma_alloc_coherent" (Baoquan He): Remove redundant GFP_DMA flags from coherent DMA allocation calls. The DMA API already selects the zone from device limits and ignores the caller's flag. - "kselftest: mm: fix intermittent failure khugepaged test" (Yeoreum Yun): Propagate child-process failures in the khugepaged tests and prevent background collapse from racing their checks. This removes false passes and intermittent failures. - "MAINTAINERS: cover all hugetlb headers under HUGETLB SUBSYSTEM" (Enze Li): Cover all hugetlb headers in MAINTAINERS so get_maintainer.pl finds the right maintainers. Also label the closing hugetlb_cgroup.h include guard. Summary of the 65 singletons in this merge: The singletons include a few worthwhile performance fixes. Avoiding unnecessary reverse-map tree updates gave a reported 15.9% improvement in UnixBench's execl test on a 192-core x86 system. A reclaim retry fix stops defrag_mode from spinning under memory.low protection; a reported file-creation stress test ran 5.7 times faster, with far less memory pressure. Narrower hugetlb invalidations also spare KVM guests needless refaults: the reported Redis-in-VM P99 QPS penalty while punching holes fell from 7.09% to 1.45%. Several fixes prevent lost data or corrupted memory. Lazyfree huge-page races with mremap()/munmap() could lose data or access freed memory, and MADV_COLD could lose a concurrent write's dirty bit. Another fix prevents stale migration entries from outliving large folios. On filesystems with blocks smaller than a page, extending a file by 4 GiB or more could expose bytes written past the old EOF through mmap instead of zeroes. That is fixed, along with use-after-free races in PAGEMAP_SCAN during process exit and in memory-cgroup accounting on PREEMPT_RT kernels. Other fixes stop UFFDIO_MOVE spinning forever on pinned large folios, which could wedge other memory operations, and stop mremap() leaking commit charges until allocations fail under strict overcommit. A further fix keeps userfaultfd tracking intact on neighboring mappings. NUMA binding no longer prevents long-term pins when the chosen node has only movable memory, fixing QEMU/VFIO startup and io_uring buffer registration failures. MGLRU also gets a fix for early-boot crashes with memory cgroups disabled at boot, notably in small crash kernels. * tag 'mm-stable-2026-10-25-19-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (213 commits) mm: multi-gen LRU: fix NULL lruvec->pgdat deref with memcg disabled on cmdline mm/page_counter: use WRITE_ONCE() for emin/elow when parent is the root mm/memcontrol: publish null pointer before dropping css reference test_maple_tree: test maple_range_64 node in RCU mode maple_tree: fix maple_range_64 crashes in RCU mode mm/vma: avoid broken uffd merge on mremap tools/testing/shared: catch a failed posix_memalign() mm/damon/core: remove unreachable damos charge_{target,addr}_from mm/shrinker: allocate shrinker_info_unit from a dedicated kmem_cache riscv: mm: exclude invalid THP PMDs from page table check mm/damon/core: filter out damos address filter-split failed region fs/proc/task_mmu: pin mm_users in do_pagemap_scan() mm/mempolicy: apply bind policies against the scoped allocation zone mm/vmscan: reclaim every zone in per-node proactive reclaim mm/mremap: correctly uncharge accountable VMAs in error path mm/mremap: populate calculated fields in vrm state correctly MAINTAINERS: add an entry for MEMORY MANAGEMENT - MEMORY MAP mm: bdi: reset min_ratio after the sysfs attributes are gone mm/page_vma_mapped: continue past nonmatching huge PMDs selftests/mm: skip hugetlb cgroup v2 tests without the needed controllers ...
2 daysMerge tag 'f2fs-for-7.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "In this round, key enhancements focus on introducing a dedicated metadata cache infrastructure and dynamically parameterizing on-disk block layouts and geometry macros. Moving meta, node, and compress blocks out of the VFS page cache removes the page == block size assumption for metadata, which along with dynamic block layout descriptions paves the way for large folio and page != block support in the future. We also opt in to multigrain timestamps, add bio entry-count throttling for asynchronous write_end_io completion, and expose the resizable_tail feature via sysfs. Alongside these features, critical bug fixes resolve race conditions across compression, mmap write faults, checkpoint/shutdown, and filesystem freeze, prevent write bio splitting and GC holes on sequential zoned devices, and strengthen on-disk sanity checks for SIT/NAT bitmaps, read-only curseg entries, and device aliasing. Additional stability patches address online resize, roll-forward recovery, atomic file operations, quota handling, and dirty inode syncing livelocks. Enhancements: - implement dedicated metadata cache for meta, node, and compress blocks to decouple metadata from page cache for large folio and page != block support - dynamically describe SIT, NAT, orphan, dentry, node, and xattr block layouts and parameterize block/sector/node conversion macros - opt in to multigrain timestamps - introduce max_atc_write_bio_entry_cnt sysfs node - expose resizable_tail feature via sysfs - avoid unnecessary reads in f2fs_update_meta_block() Bug fixes: - compress: force out-place update for all writes, allow pinning empty compressed files, and fix truncate/writeback and cache population races - zone: avoid bio split and GC target block grab failure on sequential zones - quota: convert inline quota files on quotaon, fix flush failure during freeze, and restore empty string mount options - atomic/mmap: disallow mmap write and data-modifying fallocate on atomic files, avoid truncate_inode_pages_final() on live inodes, and fix races in f2fs_vm_page_mkwrite() - resize/alias: refresh pinned allocation boundary and flush SIT journal during resize, and drop pending discards before reserving device alias - sanity check: bound SIT/NAT bitmaps by checkpoint pack, check all cur_*_segno[] on readonly images, and validate multi-device on device alias - recovery/cp: release removed xattr node in roll-forward recovery, invalidate curseg on change_curseg() failure, and return -EIO for lost inode block after cp_error - fix livelock in syncing dirty inodes and preserve APPEND/UPDATE ino entries - use bio_in_atomic() in f2fs_{read,write}_end_io() - fix 32-bit shift truncation in mount option bitmasks and defragment range And a number of minor bug fixes" * tag 'f2fs-for-7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (79 commits) f2fs: compress: don't overwrite populated compress cache entry f2fs: fix to update superblock crc in sanity_check_area_boundary() f2fs: fix to fetch ino via ino_of_node() under cache lock f2fs: zone: fix to don't fail to grab GC target block on zoned device f2fs: don't use truncate_inode_pages_final() on live inodes f2fs: expose resizable_tail feature via sysfs f2fs: use BIT_ULL for mount option bitmasks f2fs: fix submit accounting for IPU writeback f2fs: fix to avoid potential reference count leak in do_garbage_collect() f2fs: refresh pinned allocation boundary after resize f2fs: flush SIT journal during filesystem resize f2fs: release a removed xattr node in roll-forward recovery f2fs: quota: fix quota flush failure during filesystem freeze f2fs: return -EIO for a lost inode block after cp_error f2fs: avoid unnecessary reads in f2fs_update_meta_block() f2fs: bound the SIT/NAT bitmaps by the checkpoint pack f2fs: opt in to multigrain timestamps f2fs: fix to use bio_in_atomic() in f2fs_read_end_io() f2fs: fix to use bio_in_atomic() in f2fs_write_end_io() f2fs: fix to invalidate curseg if change_curseg() fails ...
2 daysMerge tag 'fuse-update-7.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Add dax backing and extent map support for famfs (John Groves, Miklos) - Support large folios (Joanne) - Add selftests and documentation of caching behavior (Luis Henriques) - Add FUSE_SYNCFS request (Jimmy Zuber) - Convert readdir cache to use folios (Tal Zussman) - Lots of bug fixes * tag 'fuse-update-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (53 commits) fuse: handle extent map files in fuse_passthrough_fadvise() fuse: resolve extent maps in O(1) when possible fuse: add support for striped backing fuse: add extent map I/O support fuse: add extent map data structure fuse: add support for opening dax device as backing fuse: support opening 64 bit backing ID fuse: support 64 bit, server allocated backing ID fuse: add helpers for EIO return value with kernel message dax: use READ_ONCE() in dax_holder() dax: add fsdev_dax_from_file() fuse: fix copy_file_range reply handling race virtiofs: validate fixed-output response length fuse: don't d_drop() before d_splice_alias() virtio_fs: read the vring size under virtio_fs_mutex in ->get_tree fuse: validate folio state before pipe_buf_try_steal() in fuse_try_move_folio() fuse: rename fuse_direct_io() to fuse_do_direct_io() fuse: Forward vfs_fadvise to backing_file in passthrough mode selftests/fuse: add the missing FUSE_HAS_SYNCFS privilege test fuse: don't launder folios of a bad inode ...
4 daysMerge tag 'ntfs-for-7.4-rc1' of ↵Linus Torvalds
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 ...
4 daysMerge tag 'exfat-for-7.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat Pull exfat updates from Namjae Jeon: - Use the recalculated append position when advancing valid_size, dirty all pages involved in valid-data extension, and zero invalid tails on partial overwrites. Write-protect the folio spanning the old EOF and zero its post-EOF range when extending a file, ensuring subsequent mmap writes advance valid_size. - Make valid_size and zeroed_size atomic to prevent torn reads and lost updates. Hold the invalidate lock during truncation, and drain in-flight direct I/O before buffered writes, buffered fallback, and page-cache operations that extend valid_size. - Fall back to single-cluster allocation when a buffered write cannot allocate its entire range, allowing writes to consume the remaining free space and return a short count. - Free clusters allocated beyond EOF after failed or short writes to prevent leaked space and spurious ENOSPC errors on later writes or file extensions. - Clean block-device buffer aliases when allocating clusters so delayed directory metadata writeback cannot overwrite file data after cluster reuse. - Update used_clusters as each cluster is allocated so partial-allocation cleanup keeps free-space accounting consistent. Acquire bitmap_lock before checking available space to serialize the check with allocation. - Use swap-specific iomap operations to report allocated extents beyond valid_size as unwritten during swap activation, retaining byte-accurate SEEK_HOLE and SEEK_DATA reporting in regular I/O. - Check allocation flags, vendor GUIDs, cluster numbers, data lengths, and contiguous extents in Vendor Allocation directory entries. Read complete entry sets during lookup so malformed trailing entries cannot bypass validation. - Follow directory FAT chains to their actual end when the recorded size is too small, supporting devices that leave directory sizes stale. Handle reads after seeking past the directory end. - Clear the volume dirty flag during remount only when switching to read-only without SB_FORCE. Update percent_in_use when changing volume flags, reporting unknown usage while the volume is dirty or persistent flags prevent marking it clean. - Replace runtime division by powers of two with bit operations. - Document supported mount options, and exfatprogs, and add the documentation path to MAINTAINERS. * tag 'exfat-for-7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat: exfat: fix reading a directory whose FAT chain is longer than its size exfat: free clusters beyond EOF when a write fails or is short exfat: clean stale bdev buffers of newly allocated clusters exfat: mark straddling folio RO and zero the post-EOF range exfat: fix a large buffered write failing when the volume is nearly full exfat: zero invalid tail on partial overwrites exfat: drain in-flight DIO before buffered writes exfat: make valid_size and zeroed_size atomic exfat: dirty all new pages when extending valid_size exfat: hold the invalidate lock while truncating exfat: advance valid_size to EOF for append writes MAINTAINERS: add exFAT documentation exfat: remove runtime integer division exfat: update percent_in_use field when updating volume flags exfat: clear the volume dirty flag only when remounting read-only exfat: doc: add documentation exfat: validate vendor allocation directory entries exfat: take bitmap_lock at the start of exfat_alloc_cluster() exfat: fix used_clusters accounting during cluster allocation exfat: map allocated extents for swap activation
4 daysMerge tag 'ksmbd-for-7.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/smb Pull smb server updates from Namjae Jeon: - Add extended SMB2 directory information support. Implement FileIdExtdDirectoryInformation, FileId64ExtdDirectoryInformation, FileId64ExtdBothDirectoryInformation, FileIdAllExtdDirectoryInformation, and FileIdAllExtdBothDirectoryInformation, including reparse tags, file attributes, and initialized response padding. - Track unsigned 64-bit lock ranges in the server lock index, with conflict detection, blocking waits, cancellation, rollback, and cleanup for ranges beyond the VFS signed-offset limit. - Add configurable per-connection session limits. Reserve slots for new sessions and multichannel bindings, release them during failure and cleanup, and expose the configured limit through procfs. - Validate POSIX negotiate and CREATE contexts, including payload lengths, extension tags, duplicate contexts, dialect requirements, and share eligibility. Require POSIX opens for POSIX file, directory, and filesystem information queries. - Apply requested POSIX create modes, including mode zero, and NFS mode ACEs with special permission bits. Enforce append-only writes and base byte-range lock checks on each open's POSIX state. - Complete POSIX metadata responses with filenames, file types, permission bits, and filesystem device identifiers. Query filesystem information through the requested open and report the filesystem fragment size and response length. - Validate SMB3 encryption transform flags and ensure decrypted compound requests use the session authenticated by the transform, including requests containing compressed payloads. - Serialize negotiation with receive processing, size CREATE responses for their contexts, reserve UTF-16 terminator space in stream information, and validate WRITE data against the active compound request to prevent buffer overruns and stale-data writes. - Validate security descriptor offsets before pointer arithmetic, handle DACL offset overflow on 32-bit systems, and propagate inode ACL lookup failures safely. - Deny access through empty DACLs while retaining the owner's implicit security-management rights. Add KUnit regression coverage for DACL walk boundaries and maximal-access calculations. - Validate RPC pipe ownership for IPC$ reads and writes, and fix FSCTL_PIPE_TRANSCEIVE handle lookup and response file IDs. - Fix durable reconnect path validation for symlinked share paths, shares exporting "/", and handles opened at the share root. Check path boundaries before comparisons to prevent out-of-bounds reads and cross-share confusion. - Rebind completed durable CREATE replays to surviving channels without draining unrelated requests on the old channel. Transfer open accounting with the binding and avoid consuming additional open-file budget during durable reconnects. - Scope AppInstanceId takeovers to the matching share, path, stream, and client identity. Check access and AppInstanceVersion before closing an existing open. - Retry oplock and lease break notifications through other live channels, track queued TCP delivery, serialize acknowledgment updates, and expire unacknowledged breaks while waking blocked requests. - Keep lease tables and byte-range lock indexes independent of their original connection so surviving channels and detached durable opens retain access to lease and lock state. - Reclaim ended sessions after logoff and expiration, hold connection references for session channels, and drain procfs readers before releasing session table references. Avoid deadlocks during previous-session teardown and connection scavenging. - Prevent file publication after tree disconnect and retain tree references until final file release. Take parent dentry references during directory enumeration and serialize directory emptiness checks with readdir. - Prevent share-root removal through empty removal paths and return appropriate errors for directory zero-data requests and temporary directory attributes. - Fix named-stream writes, EOF changes, end-of-file reads, and content copying into rename targets. Reuse existing xattr names, report sizes by exact xattr name, and avoid emptying streams after lookup or permission failures. - Round allocation requests to the advertised allocation unit and avoid allocation changes that leave on-disk EOF inconsistent with the in-memory size. - Inherit FileIds across related compound requests, including CHANGE_NOTIFY, and use the existing async request machinery for notify waiting and cancellation. - Restore share configuration and Kerberos authentication compatibility with released ksmbd-tools. Advertise extended session security for raw NTLMSSP when requested by the client. - Improve Windows chained-compression compatibility, synthesized AFP_AfpInfo headers, generated short names, and UTF-16 alignment in partial normalized-name responses. - Fix interface-query locking, response chaining, link-speed reporting, and independent IPv4/IPv6 address enumeration. Display native IPv6 client addresses accurately in procfs. - Improve SMB Direct socket cleanup by reclaiming failed pending connections, skipping failed sockets during accept, avoiding indefinite disconnect waits, and handling unexpected receive opcodes without triggering kernel warnings. - Select CRYPTO_AES for SMB3 encryption, replace deprecated system workqueues, and update feature status documentation and POSIX specification references. * tag 'ksmbd-for-7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/smb: (95 commits) ksmbd: select CRYPTO_AES ksmbd: prevent share root removal through empty paths ksmbd: serialize directory emptiness checks with readdir ksmbd: fix parent dentry lifetime in directory enumeration smb/server: prevent file publication after tree disconnect ksmbd: restore Kerberos logins with released ksmbd-tools smb/server: replace deprecated system workqueues ksmbd: reject FILE_ATTRIBUTE_TEMPORARY on directories ksmbd: deny access for an empty DACL instead of granting the request ksmbd: reject foreign RPC pipe handles on IPC$ read and write ksmbd: fix fd_limit accounting across durable reconnects ksmbd: drain session procfs readers before dropping table references ksmbd: reclaim ended sessions on logoff and expiration ksmbd: limit sessions on each connection ksmbd: hold a connection reference for each session channel ksmbd: defer connection scavenging while session locks are busy ksmbd: accept share config responses from ksmbd-tools before 3.5.3 ksmbd: round SetAllocation to the advertised allocation unit ksmbd: avoid restoring only in-memory EOF after allocation change ksmbd: inherit FileIds in related compound requests ...
4 daysMerge tag 'nfs-for-7.4-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds
Pull nfs client updates from Anna Schumaker: "New Features: - Modernize the direct I/O path - Size the LAYOUTGET reply buffer for wide flexfiles layouts - Flexfiles device notifications and caching for wide striped layouts - isolate mTLS client credentials by network namespace Bugfixes: - Various localio, flexfiles, xprtrdma, and TLS fixes - Merged bugfixes from Trond that he was unable to send during the 7.3-rc cycle Other Cleanups and Improvements: - Split up pNFS block layout and SCSI layout support" * tag 'nfs-for-7.4-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (68 commits) nfs/localio: pin UUIDs during global invalidation NFSv4/flexfiles: fail I/O to the data server once a lock is lost pNFS/flexfiles: don't report an interrupted DS connect as a DS error pNFS/flexfiles: make pg_init retry loops killable nfsv4/pnfs: use the MDS authflavor for data server connections xprtrdma: trim head iovec when the payload arrives via a Write chunk nfs: set gencount on protocol-specific remove xprtrdma: prevent disconnect feedback during endpoint teardown NFS: add a key type that reveals the namespace .nfs keyring serial number NFS: name the namespace .nfs keyring in the x509 handshake SUNRPC: pass a keyring serial number to the TLS handshake NFS: allocate the .nfs keyring per network namespace NFS: name the init_nfs_fs() error labels NFS: return DENIED in decode_lock_denied if we cannot decode owner pNFS/flexfiles: don't reset to MDS for v4 error when previous layout forbid it pNFS/flexfiles: don't read through MDS when previous layout forbid it pNFS/flexfiles: honor FF_FLAGS_NO_IO_THRU_MDS over the mdsthreshold hint NFS/localio: report the stability a DIO WRITE actually has NFS/localio: detect a short read or write before the iterator has moved NFS/localio: fix nfs_local_dio_misaligned tracepoint ...
5 daysMerge tag 'efi-next-for-v7.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI updates from Ard Biesheuvel: - Set the LoaderDevicePartUUID EFI variable from the stub to help systemd discover the file system layout when booting straight into Linux without GRUB or systemd-boot (Vincent Mailhol) - Some GUID deduplication work from Vincent - Remove pointless UTF16->UTF8 and vice versa conversions from the stub - Some kmap() -> kmap_local_page() conversions in the capsule loader - Add a runtime control to en/disable EFI runtime services so that PREEMPT_RT systems can enable them as needed - Add a 'nostatfs' mount option to efivarfs so that the cost of querying the EFI variable store (which is already rate limited) can be avoided entirely on systems where it is disproportionately costly - Rework the EFI libstub Makefile to align x86 with other architectures, and inherit/adapt the global CFLAGS variable rather than reconstruct it from scratch - Constify attributes of statically allocated sysfs nodes - Avoid register x18 when building the arm64 EFI stub, in order to comply with the UEFI spec, and to permit it to execute in a context where x18 is special - Preserve the physical addresses of all EFI config tables that may be of interest to an incoming kexec kernel - Add some LKDTM tests for EFI runtime crashes where the faulting address is inside a EFI memory region - Other minor bug fixes and cosmetic cleanups * tag 'efi-next-for-v7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: (35 commits) lkdtm: Add more EFI runtime tests efi: Initialize all configuration table addresses to EFI_INVALID_TABLE_ADDR efi: Retain the address of the LINUX_EFI_MEMRESERVE table efi/libstub: Don't replace an existing LINUX_EFI_MEMRESERVE table efi/runtime-wrappers: Don't park the worker after a recovered firmware fault efi: Use sysfs_emit() not sprintf() to generate sysfs file contents efi: Constify sysfs attributes efi/libstub: Disable kernel stack erasing in the common flags efi/libstub: Build the x86 stub from KBUILD_CFLAGS efi/libstub: Declare the x86 stub's assembly entry points efi/libstub: arm64: Don't use the platform register x18 efi/libstub: Free cmdline_ptr in efi_pe_entry efi/riscv: libstub: Don't set image_size in handle_kernel_image() efi/libstub: Fix error unwind freeing fdt in allocate_new_fdt_and_exit_boot() efivarfs: add nostatfs mount option to skip QueryVariableInfo() efi/libstub: add initial Boot Loader Interface support efi/libstub: Add efi_snprintf() to construct wide strings efi/libstub: Add support for printing human readable GUIDs efi/libstub: Output UTF-16 directly from vsnprintf() efi/libstub: Avoid efi_puts() for compile time constant strings ...
6 daysdocs: filesystems: update mmap_prepare docs for discontig kernel pgsLorenzo Stoakes (ARM)
Describe the newly introduced discontiguous kernel page mapping mechanism, detailing how to use it sensibly and how the API looks. Explicitly detail the various discontiguous actions available and how to use them. Link: https://lore.kernel.org/20261013-b4-mmap-prepare-vma-flag-sanify-v6-9-1aa3c9b139f9@kernel.org Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Liam R. Howlett <liam@infradead.org> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Mike Rapoport <rppt@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Leon Romanovsky <leon@kernel.org> Cc: Paul Moore <paul@paul-moore.com> Cc: Stephen Smalley <stephen.smalley.work@gmail.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Nico Pache <nico.pache@linux.dev> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Barry Song <baohua@kernel.org> Cc: Lance Yang <lance.yang@linux.dev> Cc: Usama Arif <usama.arif@linux.dev> Cc: Kiryl Shutsemau <kas@kernel.org> Cc: Doug Gilbert <dgilbert@interlog.com> Cc: James Bottomley <james.bottomley@hansenpartnership.com> Cc: Martin K. Petersen <mkp@kernel.org> Cc: Simona Vetter <simona@ffwll.ch> Cc: Helge Deller <deller@gmx.de> Cc: Sebastian Reichel <sre@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Peter Xu <peterx@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Rik van Riel <riel@surriel.com> Cc: Harry Yoo <harry@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: David Airlie <airlied@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Jan Kara <jack@suse.cz> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oupton@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Anup Patel <anup@brainfault.org> Cc: Paul Walmsley <pjw@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Janosch Frank <frankja@linux.ibm.com> Cc: Claudio Imbrenda <imbrenda@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Gregory Price <gourry@gourry.net> Cc: Ying Huang <ying.huang@linux.alibaba.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Chris Li <chrisl@kernel.org> Cc: Kairui Song <kasong@tencent.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Baoquan He <baoquan.he@linux.dev> Cc: Youngjun Park <youngjun.park@lge.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Qi Zheng <qi.zheng@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Wei Xu <weixugc@google.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Michal Hocko <mhocko@kernel.org> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Xu Xin <xu.xin@linux.dev> Cc: Ihor Solodrai <ihor.solodrai@linux.dev> Cc: Bert Karwatzki <spasswolf@web.de>
6 daysMerge tag 'mm-stable-2026-10-19-21-33' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "selftests/mm: improve khugepaged coverage" (Kiryl Shutsemau): Give khugepaged a proper workout. Extend the tests to all supported mTHP orders, check exactly which windows collapsed, and make scan completion deterministic. Race collapse against faults, pinning, fork and remap; verify that the contents survive. Add coverage for whole-page-table zaps and memory pressure too. - "selftests/mm: separate GUP microbenchmarking from functional testing" (Sarthak Sharma): Untangle GUP benchmarking from correctness testing. Move the benchmark into tools/mm, add a standalone harness-based GUP selftest, and move shared helpers into tools/lib/mm. Give each tool one job instead of mixing timing measurements with correctness checks. Cover the mapping, pinning and batch-size combinations explicitly. - "mm: Switch device DAX to section-based vmemmap optimization" (Muchun Song): Apply section-based vmemmap optimization to device DAX. Rework the backing metadata layout to save memory while preserving the handling of device memory hotplug and its different alignment and lifetime requirements. - "mm: Introduce section-based vmemmap optimization for HugeTLB" (Muchun Song): Cut the memory consumed by HugeTLB's struct page array with section-based vmemmap optimization. Arrange the metadata so large huge pages need fewer backing pages, while keeping initialization, teardown and the various hugepage configurations straight. - "mm/huge_memory: clean up and decouple the anon and file split helpers" (Kairui Song): Separate anonymous and file-backed folio splitting, which have rather different locking and bookkeeping requirements. Move the work into separate helpers, drop dead checks and tidy swap-cache handling. Fix error paths, including one that could leave a folio frozen. Keep the swap cache cases separate from file-cache splitting. - "mm: Unconditional per-VMA locks and cleanups" (Dave Hansen): Make per-VMA locking unconditional and clean up the old conditional code around it. This removes configuration-dependent plumbing and lets callers depend on one locking model rather than carrying both cases along. - "memcg: remove the v1 soft limit" (Shakeel Butt): Remove the old cgroup v1 memory soft-limit machinery. This has long since been superseded by the newer memory-control interfaces; hauling around a separate reclaim scheme for it no longer buys us much. - "read proc/pid/smaps_rollup under per-vma lock" (Suren Baghdasaryan): Read /proc/PID/smaps_rollup using per-VMA locks where possible, rather than holding mmap_lock across the entire walk. Retain the contention fallback and add tearing tests. This considerably reduces latency when another thread is busy changing its mappings. - "mm/damon: introduce data access-as-a-data attribute" (SJ Park): Teach DAMON to expose memory access observations as data attributes, making them available to the probe and filtering machinery. Extend the interfaces, documentation and tests so the new information can be used rather than merely collected. - "Remove PG_private by using page/folio->private checks instead" (Zi Yan): Get rid of PG_private and use the folio's private pointer to say whether private data is attached. Convert the filesystem users, including erofs, f2fs and md, and clean up the old accessors and flags. There are a few special cases, notably swapcache and hugetlb, which need explicit care. - "mm: make userland page table freeing RCU-safe" (Lorenzo Stoakes): Make freeing userspace page tables safe against RCU readers. Sort out the page-table lifetime and locking rules so walkers cannot stumble over freed tables while mappings are being torn down. - "make unused huge shrinker memcg aware" (Qi Zheng): Make shmem's unused-huge-folio shrinker aware of memory cgroups, so reclaim can find those folios under the right memcg. Wire up the per-memcg tracking and its lifetime rules, and give the shrinklist its own lockdep class to avoid spurious dependency reports. - "mm: Drop pxd_ERROR()" (Anshuman Khandual): Remove the old pxd_ERROR() page-table checks and their architecture-specific baggage. Simplify the common page-table interfaces and callers now that these checks no longer serve a useful purpose. - "memcg: group struct fields by access pattern" (Shakeel Butt): Rearrange memcg's hot and cold fields according to how they're actually accessed. Keep frequently updated counters and their neighboring state from fighting over cachelines and reduce needless cacheline traffic. - "mm/damon/core: fix the size charged for a filter-trimmed region" (Donggeun Yoo): Fix DAMOS quota accounting when a filter trims a monitoring region. Charge only the part left after filtering, not the original region, and add KUnit coverage. Previously the excluded memory could eat into the quota and make schemes run more slowly than requested. - "mm/damon: add kunit and selftests for probes and probe weights" (SJ Park): Add more tests for DAMON probes and their weights, including validation and the results reported to userspace. This is mostly about catching regressions in the newer probe infrastructure before they become harder to diagnose. - "mm: memcontrol: constify the read side of the read side of the memcg API" (Tal Zussman): Mark the read-only parts of the memcg interface const, from folio and lruvec accessors to counters and swap helpers. Most of this is mechanical, but it makes the contracts clearer and lets the compiler catch accidental writes. - "mm/damon/vaddr: support {prep,apply}_probes" (SJ Park): Support the new prepare/apply probe operations in DAMON's virtual-address backend. This brings vaddr monitoring into line with the probe infrastructure and makes the added probe types useful there too. - "mm/mglru: clean up folio counters and flag usage" (Kairui Song): Simplify MGLRU's folio counters and flag handling. Remove redundant accounting paths and make the state transitions easier to follow without changing the intended reclaim policy. - "arch, mm/execmem: resolve confusion about set_direct_map_valid_noflush()" (Mike Rapoport (Microsoft)): Clarify and straighten out the set_direct_map_valid_noflush() interface across architectures and execmem. Make the requested mapping changes and the callers' expectations agree, rather than relying on subtly different architecture behavior. - "mm: zswap: free cold writeback folios promptly" (Alexandre Ghiti): Free zswap writeback folios as soon as their disk write completes. They are cold temporary buffers, so putting them on the LRU only makes reclaim rediscover them later. Extend swap-cache dropbehind and let zswap keep these folios off the LRU altogether. - "mm: gup: cleanup gup_fast call chain" (Aristeu Rozanski): Clean up the GUP-fast call chain and simplify how the fast-path helpers pass their arguments and results around. Keep the page-pin behavior the same while making the call sequence easier to maintain. - "mm: optimize zone-device memmap initialization" (Li Zhe): Speed up initialization of zone-device struct pages. Avoid redundant work when setting up large device-memory ranges, where touching every descriptor can get expensive. - "mm/zswap: shrink zswap_entry via a pool id" (Jianyue Wu): Reduce the size of zswap_entry by storing a compact pool identifier instead of a full pointer. Keep the pool lookup and lifetime handling correct while saving per-entry metadata. - "mm/damon: support access monitoring of hugetlb-backed memory" (Krishna Iyer): Let DAMON monitor hugetlb-backed memory too. Extend the relevant access checks and add coverage so those mappings no longer fall through a hole in the monitoring machinery. - "mm/execmem: fixes and cleanups for the ROX cache" (Mike Rapoport): Tidy execmem's read-only-executable cache and fix its handling of the awkward allocation and release cases. The aim is to make the cache's ownership and permission transitions more predictable. - "zsmallc: remove old object read API" (Sergey Senozhatsky): Drop zsmalloc's old object-read API and move its remaining users to the supported access mechanism. This removes a duplicate interface which we no longer need. - "mm/mempolicy: stop copying state in the interleave paths" (Gregory Price): Stop copying mempolicy state in the interleave paths when a reference to the existing policy will do. This avoids extra work and makes the ownership rules less obscure. - "mm/mglru: speed up inc_min_seq() and fix cold/hot inversions" (Barry Song): Make MGLRU's generation advancement cheaper and fix cases where cold and hot folios end up in the wrong order. Adjust the counter and list handling so reclaim doesn't keep passing over the better eviction candidates. - "mm: Fix MF_DELAYED handling on memory failure" (Lisa Wang): Treat MF_DELAYED as a partially completed memory-failure operation, not an outright failure. Propagate that result correctly through shmem and the generic handler, fix the extra-reference accounting, and add tests for the resulting SIGBUS behavior. - "tools/mm/page_owner_sort: fix --sort, add module filter, improve usage" (Ye Liu): Fix page_owner_sort's --sort handling, add module-based filtering and make the usage output more helpful. This makes the tool less frustrating when tracking down who is holding on to pages. - "mm/damon: move damos filter range arguments validation to core" (SJ Park): Move DAMOS filter range validation into the core, where all callers can share it. Also close the sysfs read-twice races which could pass inconsistent ranges, and add tests for invalid input. - "mm/damon: misc cleanups" (Zenghui Yu): Clean up a collection of small DAMON rough edges in the core, interfaces and tests. No large behavior change here, just simpler code and fewer opportunities for confusion. - "mm/damon: cleanup code, add test cases, and update guidances in docs" (SJ Park): Clean up DAMON's core and interfaces, add missing test cases and bring the documentation into line with the code. These changes should make the newer facilities easier to understand and maintain. - "mm/damon: introduce hugepage_size probe filter" (SJ Park): Add a DAMON probe filter for hugepage size. Let users select a range of folio sizes through sysfs, validate the range and document the new interface, so monitoring can concentrate on memory backed by the desired hugepage sizes. - "selftests/mm: pagemap_ioctl test fixes and cleanups" (Zenghui Yu): Fix some pagemap ioctl test assumptions and clean up their setup and reporting. Make failures point to the operation that went wrong rather than to test harness bookkeeping. - "mm: avoid large folio splits when swap is unavailable" (Johannes Weiner): Avoid splitting large folios merely to attempt swap when no swap space is available. There is little point paying for an expensive split when reclaim cannot actually swap the resulting pages out. - "mm: workingset: fix the shadow node budget under MGLRU" (Hui Zhu): Fix the workingset shadow-node budget with MGLRU enabled. Keep the shadow entries within the intended limits so refault tracking does not quietly consume more metadata than it should. - "selftests/mm: TAP output and global-state fixes" (Song Hu): Fix selftests which produce misleading TAP output or fail to restore global settings after a run. A test ought to leave the system as it found it, particularly when a whole suite follows behind. - "mm: remove page_swap_entry()" (Tal Zussman): Remove page_swap_entry() and convert its remaining users to the folio and swap-entry helpers. Lose an old page-level interface and make the swap paths a little more consistent. - "mm: refactor zonelist constructors and iterators" (Gregory Price): Refactor the zonelist construction and walk helpers to reduce duplicated logic. Keep the allocation ordering rules intact while making it clearer how zones are selected. - "mm: kmemleak: batch the struct page scan" (Breno Leitao): Scan adjacent struct pages in batches instead of taking kmemleak_lock once for every single page. This preserves scan coverage and the lock-hold bound, while cutting overhead substantially on debug kernels. - "mm/damon: misc improvements in tests and documents" (Zenghui Yu): Fix some DAMON selftests which leave kdamond running or fail under Python safe-path mode, and improve the KUnit coverage and documentation. Nothing especially glamorous, but these are worth doing. - "mm/damon: introduce probe_hits_wsum DAMOS core filter" (SJ Park): Add a DAMOS core filter using weighted probe-hit counts. This gives schemes another way to select regions based on what the monitoring probes observed. - "mm/mglru: fix ineffective memory protection for non-kswapd reclaim" (Ridong Chen): Fix MGLRU's memory protection handling for reclaim outside kswapd. The protection settings weren't having the intended effect in these paths, leaving protected memory more exposed than requested. - "mm/damon: improve readability, clarity and test coverage" (SJ Park): Simplify a handful of DAMON core helpers, clarify their behavior and expand test coverage. There are no intended userspace-visible changes in this batch. - "mm: replace PF_KCOMPACTD/PF_KSWAPD with kthread_func()" (Kefeng Wang): Stop identifying reclaim and compaction workers through the PF_KSWAPD and PF_KCOMPACTD task flags. Use their kthread functions instead and remove the redundant flag plumbing. - "mm/hugetlb: fix surplus accounting and availability checks during demotion" (Longlong Xia): Fix HugeTLB surplus accounting and availability checks when demoting huge pages. Keep the counters and reservation decisions consistent as one huge page turns into several smaller ones. - "mm/damon: add kunit tests for probe_hits handling and probe params validation" (Jason Angelov): Add KUnit tests for DAMON probe-hit handling and invalid probe parameters. These cover edge cases that were too easy to miss in ordinary monitoring tests. - "mm/damon: fix misc bugs in kunit, quota goals and sysfs refresh_ms" (SJ Park): Fix a few DAMON bugs in KUnit tests, quota-goal handling and the sysfs refresh interval. Small fixes, but the incorrect results and control behavior were real. - "mm: zswap: optimize zswap invalidate and store" (Kefeng Wang): Simplify zswap's invalidate and store paths to avoid avoidable lookups and work. Keep the entry lifetime rules intact while making those frequent operations cheaper. - "mm: replace custom ratelimiting logic" (Pedro Falcato): Replace hand-rolled MM rate limiting with the common kernel helpers. There is no need to maintain another local version of the same mechanism. - "mm/vmalloc: minor cleanups" (Ye Liu): Tidy some vmalloc initialization and reporting code, and pull duplicated vmap-area insertion work into a helper. No functional changes are intended. - "mm/mglru: clean up isolate_folios for readability and clarity" (Ridong Chen): Clean up MGLRU's isolate_folios() so the decisions are easier to read and verify. Keep reclaim behavior unchanged while removing unnecessary twists in the control flow. - "Catch automatic storage in IDA and Maple Tree definitions" (Yury Norov): Catch IDA and maple-tree definitions placed in automatic storage where the lifetime rules are wrong or easy to get wrong. Add checks so such mistakes are harder to slip through unnoticed. - "mm, swap: some random fixes and cleanups" (Kemeng Shi): Fix and simplify a few unrelated swap paths, removing redundant work and tidying up error handling. A small collection of things which were better fixed than left lying around. - "mm/page_io: folio conversion cleanups" (Tal Zussman): Finish some page-to-folio conversions in swap I/O, removing obsolete wrappers and using folio operations consistently. The I/O behavior is intended to remain the same. - "mm/swap: skip empty clusters in the swapoff scan" (Youngjun Park): Skip empty swap clusters during swapoff instead of walking slots which have nothing to release. This avoids pointless work on sparsely used swap devices. - "mm: trace: decode architecture-specific VMA flags" (Meijing Zhao): Teach the VMA trace output to decode architecture-specific flags, rather than leaving them as unexplained bits. That should make tracing a good deal more useful when debugging unusual mappings. - "mm, swap: don't spin on a bad swap entry" (Breno Leitao): Stop repeatedly retrying a swap entry which is already known to be bad. Make the error path terminate cleanly instead of wasting CPU chasing an entry that cannot be used. - "mm/page_isolation: fix UBSAN shift-out-of-bounds in isolate_single_pageblock" (Qi Xi): Fix an out-of-range shift in isolate_single_pageblock() and tighten its associated boundary handling. UBSAN found the issue; the result should be more robust pageblock isolation. - "mm: khugepaged: fix tracepoint UAF" (Vernon Yang): Fix a use-after-free in khugepaged tracepoint handling. Make sure the information recorded by tracing stays valid for as long as the trace event needs it. - "mm/damon: fix DAMOS bugs in core, paddr and vaddr" (SJ Park): Fix several DAMOS problems across the core and physical- and virtual-address backends. The changes close error cases and bring the implementations back into agreement. - "mm/hugetlb_cgroup: move the per-node usage along with the folio" (Hongfu Li): Move HugeTLB per-node usage accounting when folios migrate between nodes or are reparented to another cgroup. Otherwise numa_stat can retain stale charges and even underflow when the folio is freed. - "docs/core-api: memory-allocation: add k[mz]alloc_obj() and clarify kmalloc" (Mike Rapoport): Document the typed k[mz]alloc_obj() allocation helpers and clear up some kmalloc guidance. Make it easier for callers to choose the right interface. - "selftests/mm: Validate selections and scope memfd_secret setup" (Tianyi Chen): Check selftest selections before running and confine memfd_secret setup to the cases that actually need it. Avoid confusing failures caused by the test harness itself. - "mm/damon: move zero damos quota target_value handling to the core layer" (SJ Park): Handle a zero DAMOS quota goal target in the core rather than making each user of the interface invent its own rule. Keep quota decisions consistent across callers. - "mm/damon: Introduce a huge page collapsing mechanism using auto tuning" (Asier Gutierrez): Add an auto-tuned DAMON mechanism for collapsing huge pages. Use monitoring feedback to decide when collapse is worthwhile rather than forcing one fixed policy onto every workload. - "kmemleak: fix stale documentation and raise the verbose default" (Breno Leitao): Bring the kmemleak documentation up to date and require a third confirming scan before verbose kernels print a suspected leak. The extra scan helps suppress transient false positives in noisy debug builds. - "mm/memory: improve insert_pages() error handling" (Avi Weiss): Tighten insert_pages() error handling so partial failures are reported and cleaned up consistently. The caller should not have to guess how far the operation got. - "mm/damon: allow NULL or unstarted damon_ctx parameter for damon_call()" (SJ Park): Make damon_call() handle NULL and not-yet-started contexts safely. Simplify the rules for callers and avoid an indefinite wait on an invalid state. - "mm/damon: introduce pgidle_set probe filter type" (SJ Park): Add a pgidle_set DAMON probe filter, giving monitoring users another way to select pages by their idle-tracking state. Wire it through the filter interfaces and tests. - "mm/damon/core: remove unused helper functions" (Cheng-Han Wu): Remove DAMON core helpers which no longer have callers. Keep the API surface smaller rather than retaining dead code just in case. - "mm: stop calling pmd_folio() on special PMDs" (Gregory Price): Avoid calling pmd_folio() on special PMD mappings that have no struct page. The old assumption could fault in procfs walkers; use the normal-folio checks and handle those mappings properly. - "mm: remove three unused helpers from mm.h" (Tal Zussman): Remove three unused helpers from mm.h. Fewer obsolete interfaces for the next person to stumble over. - "mm/damon: improvements in efficiency, error handling, documents" (Liew Rui Yan): Skip needless DAMOS quota work once the quota is full, propagate a missing sysfs error and tidy a couple of comments. The ignored error could make a monitoring-start request appear successful when it wasn't. - "docs/mm/damon/design: add explanation of nr_snapshots" (Liew Rui Yan): Explain DAMON's nr_snapshots accounting in the design documentation and straighten out the associated terminology. Make it clearer what users should expect from that counter. - "selftests/cgroup: fixes for test_zswap on single core VM" (Wilson Felipe Pereira): Fix two test_zswap failures on single-CPU VMs. Wait for the exiting child's cgroup to become unpopulated before reconfiguring it, and avoid another test assumption which breaks under constrained scheduling. - "docs/ksm: fix advisor documentation and comment" (Jinjiang Tu): Correct the KSM advisor documentation and a misleading code comment. Keep the description aligned with how the advisor actually works. - "Fix bugs in HugeTLB allocation when mem_cgroup_charge_hugetlb() fails" (Ackerley Tng): Fix HugeTLB allocation cleanup when the memcg charge fails. Make sure failure exits undo what was allocated rather than leaving stale accounting or resources behind. - "mm, memcg: fix memory.peak reset clobbering other fds' watermark" (Ridong Chen): Fix memory.peak reset handling so resetting one file descriptor doesn't overwrite the watermark kept for another. Keep those per-open measurements independent as intended. - "mm: reject zone device folios in more folio walkers" (Gregory Price): Reject zone-device folios in page walkers that cannot safely handle them. Extend the existing checks rather than assuming every folio has ordinary system-memory backing. - "percpu: remove code with no effect" (Sang-Heon Jeon): Remove a few pieces of percpu code which no longer do anything. There is no reason to keep maintaining dead paths. * tag 'mm-stable-2026-10-19-21-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (539 commits) mm: shmem: assign a lock class to the unused huge shrinklist mm: vmscan: put rotation-missed folios at the LRU tail mm: kmemleak: scan the struct page array in MAX_SCAN_SIZE batches mm: kmemleak: move the struct page scan into a helper mm/damon: document that a zero sample_interval is accepted mm/damon: fix typos in comments mm/damon/sysfs: propagate damon_call() error in turn_damon_on mm/damon/core: skip quota score setup when the quota is full mm/damon/tests/core-kunit: test the size charged for a filter-trimmed region mm/damon/core: charge only the part of a region the filter left mm: disallow raw PFN mappings of huge/shared zeropage selftests/mm: zap whole PTE tables in the khugepaged race harness selftests/mm: add memory-pressure threads to the khugepaged race harness selftests/mm: race the collapse of windows with holes selftests/mm: add khugepaged race harness selftests/mm: check that one khugepaged pass collapses one window selftests/mm: run every supported collapse order by default selftests/mm: cover a shared-source collapse write race selftests/mm: parameterize the mixed-source collapse case by source order selftests/mm: add order-parameterized khugepaged collapse cases ...
8 daysMerge tag 'kbuild-7.4-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux Pull Kbuild / Kconfig updates from Nathan Chancellor: "Kbuild: - Suppress compiler flags in debug info for external module builds - Use '-fmacro-prefix-map' in more places in the build - Merge initial set of changes from Lorenzo's speed up series, along with some fixes found through testing: - Avoid allocating .modinfo in vmlinux - Speed up kallsyms by indexing symbols by token and outputting binary data to disk directly then including in assembly via .incbin - Don't sort $(NM) output when unnecessary - Only emit relocations on the final vmlinx link - Reimplement mksysmap in C - Move many cc-option and ld-option calls into the Kconfig stage to cache their results - Use pigz for gzip compression when available - Move gen_init_cpio and gen_initramfs.sh from usr/ to scripts/ - Add a TOML configuration to scripts/container and update documentation accordingly - Add a generic, opt-in mechanism for checking that headers can compile standalone - Update machine function splitting argument for LLVM 24 rename in AutoFDO build - Miscellaneous minor clean ups, fixes, and hardening, mostly found/fixed via LLMs Kconfig: - Turn recursive ranges into an error - Fix savedefconfig for defaults that were adjusted for being out of range and revert a previously applied workaround - Improvements and hardening around integer and hexadecimal values - Emit a warning when selecting or implying a choice symbol, which has no effect - Emit a warning when KCONFIG_PROBABILITY is malformed - Introduce def_string / def_int / def_hex to mirror the existing def_bool / def_tristate to succinctly set a value and type at the same time. - Add cc-option-str and ld-option-str macros to act like Kbuild's cc-option and ld-option, returning the string when the option is supported, allowing many checks to be moved into Kconfig - Minor usability improvements to Kconfig tests" * tag 'kbuild-7.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (59 commits) kbuild: AutoFDO: Update split machine function argument for upstream rename kbuild: Mark the initcall ordering recipe as recursive kbuild: Mark the gzip recipes as recursive localmodconfig: Explicitly report boolean configs during integrity check scripts/make_fit: Ignore schema checks when decomposing DTBs clang-tools: Import os for broken pipe handling kconfig: use the value argument in sym_get_near_range_bound() kconfig: fix infinite loop in conf_choice() when no choice value is visible kconfig: cleanup stale comment about 'keys' array kconfig: Improve ergonomics around disabling warnings with cc-option scripts/Kconfig.toolchain: Drop compiler symbols from dependencies checkkconfigsymbols.py: Parse Git status output line by line gen_init_cpio: stop parsing on lines with a missing argument list .gitignore: drop Module.markers .gitignore: ignore pacman package signatures kbuild: add header check facility as a manually run static analyzer Documentation: dev-tools: refer to user ID rather than id Documentation: dev-tools: update container.rst with config file scripts: add TOML config to container tool kconfig: tests: {old,save}defconfig: Forward dynamic keyword arguments ...
9 daysMerge tag 'erofs-for-7.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs Pull erofs updates from Gao Xiang: "The most notable change is to support superblock sharing for composefs, thanks to Giuseppe again. Another one switches to iomap for file-backed mounts on unencoded inodes, which enables efficient sub-folio I/Os. The others are all random ones. Summary: - Support superblock sharing for file-backed mounts - Use iomap for file-backed mounts on unencoded inodes - Minor fixes and cleanups" * tag 'erofs-for-7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: enable iomap for file-backed mounts on unencoded inodes erofs: use on-disk blkszbits for lz4 max pcluster bound mailmap: update entry for Gao Xiang MAINTAINERS: erofs: update my email address erofs: reuse superblock for file-backed mounts MAINTAINERS: erofs: add dev branch to git tree entry erofs: fix xattrs handling when metadata compression is used
9 daysMerge tag 'xfs-merge-7.4' of git://git.kernel.org:/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull xfs updates from Carlos Maiolino: "The bulk of this are bug fixes, cleanups and code refactoring, lots of them. Majority of those bug fixes are targeting scrub and online repair code. There are no real new features here but lots of prep code for future work. There are also some small performance optimizations but nothing major" * tag 'xfs-merge-7.4' of git://git.kernel.org:/pub/scm/fs/xfs/xfs-linux: (168 commits) xfs: don't limit software atomic writes by the group alignment xfs: add missing cursor stat checks after xfs_btree_delete xfs: add missing cursor status check after xfs_inobt_get_rec xfs: handle NULL open_zone for merged ioends in xfs_end_ioend_write_zoned xfs: refactor inode forkoff to byte conversions xfs: drop unnecessary sr parameter from xchk_rtgroup init functions xfs: drop unnecessary sa parameter from xchk_ag init functions xfs: drop unnecessary sr parameter from xrep_rtgroup init functions xfs: drop unnecessary sa parameter from the xrep_ag init functions xfs: improve dirent bounds checking in scrub and repair xfs: refactor directory data block walking loops in scrub xfs: update quota flags on secondary supers when metadir enabled xfs: don't try to repair rtsummary if the summary file isn't computed xfs: rescan the AGs if incore delalloc counter is negative xfs: don't rescan ifree and icount when frozen xfs: don't set a metadata directory's parent to sb_rootino xfs: don't scan across metadata/regular directory trees for dirents xfs: always report scrub errors in tracepoints xfs: opportunistically skip btree block checks xfs: clear set[ug]id mode bits when zapping attr fork ...
9 daysMerge tag 'docs-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It was a reasonably busy cycle for docs; changes include: - Add the AGENTS.md symbolic link into the top-level directory in the hopes that LLMs will read it and produce better work - The removal of the Assisted-by requirement, as concluded at the Maintainer Summit - A new "testdocs" make target to run the documentation unit tests - Lots of work on the Portuguese, and Chinese translations; there is now maintenance for the traditional Chinese translations as well ...and the usual pile of minor fixes, documentation updates, etc" * tag 'docs-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (125 commits) docs: add AGENTS.md as a symlink to README docs: kernel-parameters: adjust reserve_mem build option docs: kernel-parameters: don't mix cmdline options & build options docs/ja_JP: translate submitting-patches.rst (review and report tags) docs: remove Assisted-by references Revert "docs: landlock: fix ENOMSG condition in create_ruleset kernel-doc" docs: kdoc: parse context_lock_struct() as struct declaration docs: timers: hpet: Document userspace API and ioctl commands docs: timers: hpet: Modernize file references Documentation: sched-preemption: Add a SPDX license identifier docs: ABI: sysfs-driver-xdata: use literal blocks for console commands docs: ABI: sysfs-class-firmware-attributes: use literal blocks for console commands ABI: sysfs-bus-usb: use literal block for console commands docs/ABI: testing: aspeed-uart-routing: use literal block for console commands docs: kernel-parameters: fix a truncated sentence for preempt=lazy sched/doc: add a preemption model overview docs: ABI: TMR manager: use literal blocks for console I/O Documentation/ABI: IFS: use literal blocks for commands ABI: sysfs-bus-pci: use literal blocks for commands docs: translations: pt_BR: add debugging index ...
9 daysksmbd: doc: update feature statusNamjae Jeon
Add MSDFS, Continuous Availability (CA), and AD/DC to the ksmbd feature status list, along with resilient handle. Mark Continuous Availability, AD/DC, persistent handle, and SMB2 notify as under development. Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
9 daysksmbd: doc: update RDMA feature support statusNamjae Jeon
ksmbd supports SMB3 encryption over RDMA, while signing over RDMA is still under development. Update the feature status table accordingly. Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
9 daysksmbd: doc: update SMB3 multichannel support statusNamjae Jeon
SMB3 request replay support is now available. Update the ksmbd documentation to reflect that SMB3 multichannel is supported. Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
9 daysexfat: doc: add documentationNamjae Jeon
Add documentation for the Linux exFAT filesystem driver, including supported mount options and exfatprogs. Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
9 daysMerge tag 'x86_cache_for_v7.4_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Borislav Petkov: - Push down into arch code the rounding of bandwidth control user values due to the different ways ARM and x86 report MBA - Fix task reporting for the default group for systems which support only bandwidth monitoring, aka Haswell vintage computing - The usual fixlets and improvements * tag 'x86_cache_for_v7.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: fs/resctrl: Ensure default group reports tasks on monitor-only systems x86,fs/resctrl: Add event group descriptions for Intel Diamond Rapids x86/resctrl: Update documented unit for the "activity" event fs/resctrl: Simplify pseudo_lock_measure_trigger() fs/resctrl: Avoid extra call to strlen() in schemata_list_add() fs/resctrl: Factor MBA parse-time conversion to be per-arch arm_mpam: resctrl: Add pass-through resctrl_arch_preconvert_bw() x86,fs/resctrl: Add resctrl_arch_preconvert_bw()
10 daysntfs: support persistent noatime attributeXuewen Wang
NTFS currently rejects FS_NOATIME_FL in its fileattr setter. This prevents users from disabling automatic access-time updates on individual files or directories with chattr +A. Store noatime in bit 3 of the private $LINUXFLAGS EA and restore S_NOATIME when loading an inode. Report and accept FS_NOATIME_FL in the fileattr callbacks, updating the in-memory flag only after the EA update succeeds. The VFS then suppresses automatic atime updates for the inode, while chattr -A restores the mount's atime policy. Document the new on-disk bit and that newly created children do not inherit the attribute. Suggested-by: Baolin Liu <liubaolin@kylinos.cn> Reviewed-by: Baolin Liu <liubaolin@kylinos.cn> Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Xuewen Wang <wangxuewen@kylinos.cn> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
10 daysntfs: persist nodump in the $LINUXFLAGS EABaolin Liu
Store nodump in bit 2 of LINUXFLAGS and allow it through fileattr_set. Report the cached persistent bit through fileattr_get and STATX_ATTR_NODUMP, including the statx supported-attribute mask. Reuse the existing EA update and inode-load paths; nodump needs no additional inode flag enforcement. Document the complete immutable, append-only and nodump bitmask. Signed-off-by: Baolin Liu <liubaolin@kylinos.cn> Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
10 daysntfs: persist append-only in the $LINUXFLAGS EABaolin Liu
Extend the persistent fileattr interface to append-only using bit 1 of LINUXFLAGS. Restore S_APPEND on inode load and update it after successful EA writes. Include append in the known-bit mask while retaining all other unknown bits. Reuse the existing VFS capability checks and EA safeguards. Document append-only alongside immutable. Both flags now survive inode reclaim and remount without changing the NTFS attribute format. Signed-off-by: Baolin Liu <liubaolin@kylinos.cn> Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
10 daysntfs: persist immutable in the $LINUXFLAGS EABaolin Liu
Add a fileattr setter for immutable and store its state in bit 0 of a little-endian u32 in the private $LINUXFLAGS EA. Reuse the standard NTFS EA attributes and restore the flag when loading an inode, so eviction and unmount do not discard the setting. Use $LINUXFLAGS to avoid the WSL-owned $LX namespace. Preserve unknown bits and delete the entry only when the entire value is zero. Reject malformed values with EUCLEAN. Reject direct xattr writes and removal to avoid bypassing fileattr permissions or stale cached state. Update the cached flags only after the EA update succeeds. Reject clearing immutable on system metadata files and files protected by sys_immutable, following inode-load policy. Do not persist a bit derived solely from this policy. Preserve append state without allowing it to be changed at this stage. Compression, encryption and mount-wide case folding remain read-only. Document the format and its Linux-only enforcement. Signed-off-by: Baolin Liu <liubaolin@kylinos.cn> Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
10 daysntfs: add fileattr query supportBaolin Liu
Add fileattr_get operations for files and directories, as well as the existing symlink and special inode operation tables. Report compression, encryption, immutable and append-only from cached inode state, and FS_CASEFOLD_FL from the mount-wide case sensitivity policy. This introduces querying only. It neither reads a private flag EA nor allows userspace to change the reported flags. Signed-off-by: Baolin Liu <liubaolin@kylinos.cn> Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
10 daysntfs: document named streamsNamjae Jeon
Document the streams_interface=windows mount option and named-stream pathname semantics, including supported forms and stream lifetime. Describe the named-stream ioctl operations, request structure, and name encoding. Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
10 daysMerge tag 'vfs-7.4-rc1.netfs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull netfs updates from Christian Brauner: "This contains the netfs and cachefiles changes for this cycle from David. Cachefiles learns to cache the most common class of files properly, files that are created or truncated, written once sequentially and closed. So far it relied on the backing filesystem's idea of what is stored and asked with SEEK_DATA and SEEK_HOLE before every read it prepared, two seeks per read, and the backing filesystem is free to insert or remove runs of zeros which produces false positives and false negatives. The object type in the state xattr is now actually set to CACHEFILES_CONTENT_{SINGLE,ALL,BACKFS_MAP} instead of zero. For files written contiguously the type is ALL, the backing file's i_size tracks how much is cached and the object size lives in the xattr, and reads skip the seeks entirely. Netfslib queries the cache occupancy through a new ->query_occupancy() method that returns up to two extents at once, ->prepare_read() only limits the size of a cache read anymore and a new ->collect_write() lets the cache update its metadata once a contiguous run of writes completes. The state xattr is preset when the tmpfile is created so ENOSPC from setxattr can't scrap a fully written cache file. Two fixes for this followed, one for resize handling where the cache's idea of the size can be stale and one for an unset error that hung a request on a failed cache write. Preparatory work converts file positions that can't be negative to uoff_t, removes the writethrough code whose locking looked like it could deadlock with ceph snapshots, makes the deprecated PG_private_2 support opt-in so mm can get its page bit back, adds helpers for the NETFS_RREQ_ALL_QUEUED barriers and adds the cache object id to the read and write tracepoints. Plus an unused header removal and two documentation fixes" * tag 'vfs-7.4-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fscache, cachefiles: Fix resize handling cachefiles: Fix unset error when calling netfs_prepare_write_failed() netfs: remove unused fscache_internal.h header cachefiles: Preset the state xattr when creating a new file cachefiles: Don't rely on backing fs storage map for most use cases netfs: Document the remote size member and its accessors cachefiles: Add a tracepoint to log insufficient space errors netfs, cachefiles: Add a couple of traces for write failure cachefiles: Clean up cachefiles_do_prepare_read() netfs: Set subrequest->source at alloc before trace emission netfs: Add some functions to wrap the all-queued handling netfs: Make deprecated PG_private_2 support opt-in netfs: Add the cache object ID to netfs_read/write tracepoints netfs: trace: Rejig a couple of the tracepoints cachefiles: Fix path of the "debug" module parameter in help paragraph netfs: trace: Change the "clear" folio traces to "endwb" netfs: Remove the writethrough code netfs: Use uoff_t instead of unsigned long long and loff_t
10 daysMerge tag 'vfs-7.4-rc1.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull misc vfs updates from Christian Brauner: "Fixes: - aio: a keyed poll completion on an epoll instance could recurse into the same epoll waitqueue lock when the result eventfd is watched by that very instance. An unprivileged process could make a CPU spin on the recursive lock. eventfd-backed poll completions are always deferred now. - fsnotify_inoderemove() is only called once the inode is really dead, no nlink and no aliases, and open_by_handle_at() can't add an alias to a dead inode anymore. The race could crash fsnotify or lose inode mark notifications. - devtmpfs: the conversion of the public instance to ->get_tree() broke reconfiguring the shared superblock's options on later mounts which made the boot time defaults permanent. A reconfigure context is kept in fc->fs_private so the parse ops can forward options to the underlying filesystem. - ufs truncated the 64-bit directory size to an unsigned int in ufs_last_byte(). A crafted image with a 4 GiB directory produced an out-of-folio read in ufs_find_entry() and, with CONFIG_UFS_FS_WRITE, a write into an adjacent page. - devpts rejects max=0 instead of silently lifting the per-instance pty limit. The value wrapped into ida_alloc_max() and became unlimited. - fs_pin publishes pins with the rcu list helpers so the kill paths reading the lists under rcu see the initialization. - dentry_kill() reports a Tasks-RCU quiescent state. Its cond_resched() is the only reschedule point on the dentry teardown path and cond_resched() isn't a quiescent state for Tasks-RCU, so Meta kept seeing rcu_tasks stalls in btrfs subvolume deletion. - writeback sizes foreign flushes by the target wb's dirty pages instead of the memcg-wide count which over or undersized a single bdi flush. - nfsd READ emitted two fsnotify access events on the iterator path since vfs_iocb_iter_read() already sends one. A READ on a krb5i or krb5p mount showed up twice in inotify. - pipe and splice pass a poll key when waking readers and writers so epoll, poll() and select() waiters only wake for the event they asked for. - the iso8859-14 Unicode to charset tables had page01 duplicated as page1e so 29 code points mapped to the wrong bytes and 22 that aren't in the charset were accepted. - orangefs doesn't wait for an unmount service operation that never returns on system shutdown and uses ssize_t for strscpy() errors. - __register_chrdev() checks the kobject_set_name() return value. - selftest fixes: the openat2 tests hardcoded O_LARGEFILE to 0x8000 which is O_NOFOLLOW on powerpc, resolve_test makes /tmp a mountpoint so RESOLVE_NO_XDEV has a boundary to trip over, file_stressor moves into its own directory with a 30 minute timeout, the kernfs listxattr test skips when SELinux exposes security.selinux, the namespaces active reference tests wait for the thread via a PIDFD_THREAD pidfd since pthread_join() returns before exit_nsproxy_namespaces(), the idmapped_tmpfile test chowns its directory into the mapped range, the clone3 CLONE_CLEAR_SIGHAND test adds CLONE_VM so it fails for the intended reason, the pidfd PPID error message prints the values it compares and fscontext_ns gets a .gitignore. Cleanups: - vmcore prints the release of the crashed kernel from the VMCOREINFO note so a kdump that dies before the dump lands still says which kernel it was for. - initramfs allocates hardlink hash entries with the validated cpio name length instead of PATH_MAX, which put every entry in kmalloc-8k. - the unused dax_layout_busy_page() is removed, dax_layout_busy_page_range() becomes static and dax_folio_init() drops a redundant list initialization. - vfs_empty_path() is removed, it has had no callers since getname_maybe_null(). - comment and documentation fixes in aio, bpf_fs_kfuncs, fs-writeback, inode, read_write, squashfs and the vfs.rst copy of struct file_system_type" * tag 'vfs-7.4-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (38 commits) selftests/filesystems: Fix idmapped_tmpfile layer dir ownership selftests/namespaces: Wait for thread exit via pidfd in active-ref tests writeback: size foreign flushes by target wb dirty pages initramfs: Reduce hardlink hash allocation sizes fs: remove unused vfs_empty_path() dcache: report a Tasks-RCU quiescent state in dentry_kill() vmcore: report the release of the crashed kernel splice: pass a poll key when waking pipe readers and writers pipe: pass a poll key when waking writers after a resize orangefs: use ssize_t instead of size_t for error codes... orangefs_super: don't wait on service operation on system shutdown. docs/vfs: Fix the struct file_system_type copy nls: fix the Unicode to charset tables of iso8859-14 selftests/filesystems/openat2: make /tmp a mountpoint inside private namespace selftests/filesystems/openat2: fix O_LARGEFILE definitions for non-arm64 architectures fs: fix misleading comments in read_write.c squashfs: fix inode number description in documentation fs: fix typos in comments fs/dax: Make dax_layout_busy_page_range() static fs/dax: Remove unused dax_layout_busy_page() ...
10 daysMerge tag 'vfs-7.4-rc1.lookup' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull path lookup updates from Christian Brauner: "This prepares for Neil's changes to directory locking. The goal is for the VFS to lock the dentry and not the parent directory and to push the i_rwsem parent locking down into the filesystems where it can be kept, removed or adjusted as each filesystem sees fit. The next step in that is to swap the lock order of d_alloc_parallel() and i_rwsem so code can wait on i_rwsem while holding an in-lookup dentry. Two things have to change before that can happen. Nobody may call d_alloc_parallel() while holding i_rwsem, and nobody may d_drop() a dentry while it is being worked on since that effectively unlocks an in-lookup dentry and lets another one be allocated too early. So d_splice_alias() learns to handle hashed dentries in addition to unhashed and in-lookup ones, which is what ->atomic_open() needs and removes the reason filesystems d_drop() first. d_alloc_trylock() is a non-blocking d_alloc_parallel() for the filesystems that prime the dcache from readdir, smb, nfs, fuse and ceph, where waiting for a concurrent lookup is pointless. d_duplicate() creates an in-lookup dentry with the name of an existing one for silly-rename and whiteouts. LOOKUP_SHARED tells ->lookup() how the parent is locked so it can drop and retake it. DCACHE_PAR_LOOKUP is tracked by lockdep now with a per filesystem type key, and overlayfs gets its own class since it stacks over itself. And a d_flags bit is reserved for filesystem private use. Also included is Mateusz's fix for the spurious dentry reference cycle on open. __legitimize_path() grabs a reference, do_dentry_open() grabs another and terminate_walk() drops the first. do_dentry_open() consumes the held reference now. Opening the same file read-only on a 20-core VM goes from 4,043,375 to 5,629,378 ops/s in will-it-scale" * tag 'vfs-7.4-rc1.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: VFS: d_duplicate: repair comments to avoid kernel-doc warnings ovl: provide private lockdep class for dentry->dep_map VFS: rename lookup_map to dep_map VFS: per-fs-type lockdep key for dentry in-lookup locking VFS: reserve a d_flags bit for fs-specific usage VFS: add lockdep monitoring of DCACHE_PAR_LOOKUP lock. VFS: Add LOOKUP_SHARED flag. VFS: add d_duplicate() VFS: introduce d_alloc_trylock() VFS: enhance d_splice_alias() to handle hashed dentries VFS: fix various typos in documentation for start_creating start_removing etc fs: avoid spurious dentry ref/unref cycle on open
10 daysMerge tag 'vfs-7.4-rc1.idmap' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs idmap constification from Christian Brauner: "This makes struct mnt_idmap const throughout the tree. A mount's idmapping is immutable. The only thing modified after alloc_mnt_idmap() is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only reads from it. That is the same model struct cred uses and the idmapping is sensitive enough to deserve it. The conversion goes bottom up through the vfs{g,u}id and fs{g,u}id helpers, the privilege checks, acl, xattr and quota and then every inode operation that takes an idmap, so ->permission(), ->getattr(), ->setattr(), ->create(), ->mkdir(), ->mknod(), ->symlink(), ->rename(), ->tmpfile(), ->get_acl(), ->set_acl() and ->fileattr_set() with their implementations in every filesystem, plus the LSM hooks. struct vfsmount, struct mount_kattr and struct kstatmount store a const pointer and nop_mnt_idmap and invalid_mnt_idmap live in rodata, so anything that tries to modify them faults instead of silently corrupting the initial idmapping" * tag 'vfs-7.4-rc1.idmap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (27 commits) fs: make nop_mnt_idmap and invalid_mnt_idmap const fs: port mnt_idmap() and file_mnt_idmap() to const mnt_idmap fs: port vfs_*() helpers to const mnt_idmap fs: port ->setattr() to pass const mnt_idmap fs: port ->getattr() to pass const mnt_idmap fs: port ->create() to pass const mnt_idmap fs: port ->symlink() to pass const mnt_idmap fs: port ->mkdir() to pass const mnt_idmap fs: port ->rename() to pass const mnt_idmap fs: port ->mknod() to pass const mnt_idmap fs: port ->tmpfile() to pass const mnt_idmap fs: port ->get_acl() to pass const mnt_idmap fs: port ->set_acl() to pass const mnt_idmap fs: port ->fileattr_set() to pass const mnt_idmap fs: port xattr to const mnt_idmap fs: port ->permission() to pass const mnt_idmap fs: port acl to const mnt_idmap fs: port inode_init_owner() to const mnt_idmap fs: port inode_owner_or_capable() to const mnt_idmap fs: port privilege checking helpers to const mnt_idmap ...
10 daysMerge tag 'vfs-7.4-rc1.coredump' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull coredump updates from Christian Brauner: "This adds sparse coredumps and per-request memory type selection to the coredump socket protocol. A coredump sent over the socket transfers every zero of every hole in every mapping. For a process with 128 threads that's 1 GB of mostly thread stacks, 8 MB reservations with a few pages touched, and the holes sit in the middle of the dump rather than at the end. The coredump_filter bit that was proposed for this stops each PT_LOAD at the last populated page. But that mask says which kinds of memory to include and propagates across fork and exec, whereas what is selected here is an encoding. The usermodehelper isn't salvagable for this either. The coredump socket already has a handshake for exactly this. A server that raises COREDUMP_RECORDS in coredump_ack->mask gets the coredump as a sequence of records, each a struct coredump_record_header followed by what it describes. The stream ends explicitly with an end record that reports the size, so a missing one means truncation. With COREDUMP_SPARSE holes cross the socket as a bare header that says how many zero bytes were skipped. Reassembling the records gives back the same coredump, so a debugger and everything else still see an ordinary core file. Numbers from the selftests: the 128 thread process sends 1424153 bytes for a coredump of 1075150848 bytes, a 256 MB mapping with the first and the last page touched sends 188793 bytes for 268890112 bytes, and with COREDUMP_RECORDS alone the record overhead is under one percent. The selftests also simulate a server uploading to a blob store that can't seek and rewrites the program headers so the object is an ordinary ELF core file without the holes. COREDUMP_MEMORY_TYPES lets the server choose what memory to dump per request instead of relying on the static /proc/<pid>/coredump_filter of the crashing task. The request carries the default types and a mask of every type the kernel knows about, the ack carries the selection. Zero is valid and dumps the program headers and notes and nothing but the mappings that are always dumped. Preparatory cleanups refuse negative skips in dump_skip_to(), chunk every write at a page so a pipe or a socket never takes a short write in the middle of a record, make the dump helpers return bool and replace the core_dumped integer with COREDUMP_STATE_STARTED and COREDUMP_STATE_TRUNCATED flags. Also included is a fix for coredump_parse() reading core_pattern while it is being modified. The sysctl handler now validates a copy and publishes it under a spinlock and the parser works on a snapshot, so a rejected pattern is never visible and the rollback logic goes away. And to_kthread()'s lockless flags read is annotated with READ_ONCE()" * tag 'vfs-7.4-rc1.coredump' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (29 commits) kthread: Annotate lockless to_kthread() flags access coredump: parse a snapshot of core_pattern selftests/coredump: test failed handshakes selftests/coredump: improve coredump size negotiation tests selftests/coredump: test COREDUMP_MEMORY_TYPES selftests/coredump: simplify the refusal tests tools: sync coredump.h header coredump: select memory types to include selftests/coredump: show how to inspect the task to decide how the coredump should be sent selftests/coredump: simulate a blob store selftests/coredump: put a hole in the middle of a sparse mapping selftests/coredump: hand the record stream to a sink selftests/coredump: test COREDUMP_RECORDS and COREDUMP_SPARSE coredump: describe the holes when COREDUMP_SPARSE is negotiated coredump: send the coredump in records if requested tools: sync coredump.h header coredump: add COREDUMP_SPARSE to the coredump socket protocol coredump: add COREDUMP_RECORDS to the coredump socket protocol coredump: clean up coredump state handling coredump: always chunk writes ...
10 daysMerge tag 'vfs-7.4-rc1.bh' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull buffer_head updates from Christian Brauner: "This stops the buffer_head write completion handlers from clearing BH_Uptodate when a write fails. A buffer whose write failed still holds exactly the data the filesystem asked to be written. It's the disk that is stale, not the buffer. Claiming otherwise has consequences. mark_buffer_dirty() warns when a filesystem redirties the buffer to retry the write, a buffer that isn't up to date gets re-read from disk which silently replaces the data with the stale on-disk copy, and the window between the write completing and BH_Uptodate being cleared is visible to anyone holding the folio lock. BH_Write_EIO already records that the last write failed. Every consumer is moved over to buffer_write_io_error(): the two core helpers in fs/buffer.c, adfs, ext2, omfs, exfat, fat, ext4, ocfs2, gfs2 and jbd2. Then write completion stops touching BH_Uptodate in both directions and BH_Write_EIO is cleared on successful completion instead of at submission, so a resubmission no longer hides an error that hasn't been fixed yet. bforget() and invalidation drop the flag so a reused block doesn't inherit someone else's write error. The groundwork for this removes b_page from struct buffer_head and lets a buffer_head point at memory outside the page cache. jbd2's shadow buffers sit on a slab folio today. A slab folio overloads ->mapping so mark_buffer_write_io_error() couldn't be called on them at all. They now point at the frozen data directly with b_folio NULL. Also included are documentation updates from Matthew for sb_bread(), sb_breadahead() and mmb_mark_buffer_dirty() and the removal of stale references to unmap_buffer() and mark_buffer_dirty_inode()" * tag 'vfs-7.4-rc1.bh' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (27 commits) buffer: Rename label buffer: Refer to folios in comments buffer: Document mmb_mark_buffer_dirty() buffer: Document sb_bread(), sb_bread_unmovable() and sb_breadahead() fs: Remove references to mark_buffer_dirty_inode() buffer: clear BH_Write_EIO when a write succeeds, not when one starts buffer: Remove reference to unmap_buffer() buffer: stop touching BH_Uptodate on write completion jbd2: check for a fast commit write error with buffer_write_io_error() jbd2: say what jbd2_freeze_jh_data()'s assertion is actually checking jbd2: report journal write errors with BH_Write_EIO gfs2: check for a metadata write error with buffer_write_io_error() ocfs2: check for a stale write error before reusing a metadata buffer ocfs2: check for a metadata write error with buffer_write_io_error() ext4: check for a metadata write error with buffer_write_io_error() fat: check for a metadata write error with buffer_write_io_error() exfat: check for a directory write error with buffer_write_io_error() omfs: check for an inode write error with buffer_write_io_error() ext2: check for an xattr block write error with buffer_write_io_error() adfs: check for a directory write error with buffer_write_io_error() ...
10 daysMerge tag 'vfs-7.4-rc1.bfs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull bfs removal from Christian Brauner: "This removes bfs, the filesystem UnixWare uses for its boot partition. It only supports contiguous files and has no subdirectories. The only data on such a partition are kernels and bootloader settings so there is no reason to access it from Linux anymore. The uapi header stays" * tag 'vfs-7.4-rc1.bfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: bfs: remove the filesystem
10 daysf2fs: refresh pinned allocation boundary after resizeWenjie Qi
Online shrink updates MAIN_SECS() but leaves resizable_tail_secno and pinned_area_max_secno unchanged. The pinned allocation limit can exceed the new main area when shrinking beyond the reserved tail. Consume the reserved tail by the number of removed sections, clamping it to zero, before refreshing the shared pinned allocation boundary. This preserves the boundary while shrinking within the reservation and limits it to the new main area otherwise, retaining the zoned limit. Save the old tail count and restore it before rolling back the geometry if the final checkpoint fails. Also bound pinned section allocation by the current MAIN_SECS(). Range evacuation temporarily reduces it before moving cursegs, while the cached pinned boundary still describes the old geometry. Otherwise, a pinned curseg can be reallocated into the range being removed. Fixes: c966d29e01bb ("f2fs: support resizable tail section and unify pinned allocation") Suggested-by: Daeho Jeong <daehojeong@google.com> Signed-off-by: Wenjie Qi <qiwenjie@xiaomi.com> Reviewed-by: Daeho Jeong <daehojeong@google.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
14 daysfscache, cachefiles: Fix resize handlingDavid Howells
Fix the resize handling in fscache and cachefiles by passing down a flag to indicate if the file is being shrunk as the cache's idea of how big the file should be may be stale and thus not useful in comparison to the object's size. The issue is that netfs_perform_write() updates the network filesystem's file's i_size as it adds data to the pagecache, but the cache isn't updated until writeback flushes that data. A truncation may then scrap that data and so the cache never sees it and doesn't update before it is told to resize. In the resize, cachefiles was comparing the new size against the current cache size and then thinking the file was being expanded. Note that this is a bit more complicated for ceph than other filesystems as ceph splits the truncation of the local pagecache and fscache to after the RPC reply handler has updated the inode record - the reply handler communicates the need for the truncation finalisation through ceph inode flags. To this end, ceph is changed such that the outstanding truncation count in the inode turns into a bool and just set instead of being incremented (the code only cares if it's zero or non-zero) and then a second bool is added to record if the file was being shrunk. Reported-by: Marc Dionne <marc.dionne@auristor.com> Fixes: 1a9fe4b6e787 ("cachefiles: Don't rely on backing fs storage map for most use cases") Signed-off-by: David Howells <dhowells@redhat.com> Link: https://patch.msgid.link/1091807.1791483394@warthog.procyon.org.uk Reviewed-by: Alex Markuze <amarkuze@redhat.com> cc: Ilya Dryomov <idryomov@gmail.com> cc: Alex Markuze <amarkuze@redhat.com> cc: Viacheslav Dubeyko <slava@dubeyko.com> cc: Paulo Alcantara <pc@manguebit.org> cc: Matthew Wilcox <willy@infradead.org> cc: v9fs@lists.linux.dev cc: linux-afs@lists.infradead.org cc: ceph-devel@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-10-15Documentation: fuse: add document on caches being used by FUSELuis Henriques
This new file aims at documenting the caches that are used by FUSE. At the moment only symlink, attributes, ACLs and readdir caches are described. Signed-off-by: Luis Henriques <luis@igalia.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2026-10-12NFS: add a key type that reveals the namespace .nfs keyring serial numberChuck Lever
The per-namespace .nfs keyring is linked into no keyring that userspace possesses, so a tool that provisions x509 credentials, or a mount helper that searches for them, cannot reach it. Every keyring operation from userspace takes a serial number, and nothing hands this one out. Register an "nfs_keyring" key type whose request_key handler runs in the caller's context, without an upcall, and instantiates the key with the serial number of the caller's namespace .nfs keyring. Userspace reads the serial number with one request_key() and one keyctl_read(). A keyring search runs before the handler does, and a task keeps its session keyring across setns(). The type carries KEY_TYPE_NET_DOMAIN so a key instantiated in one namespace does not answer a request from another. Its preparse accepts no payload but the caller's own serial number, so a key planted by add_key() cannot misdirect a later request. Register the type after register_pernet_subsys() has installed nfs_net_id, and unregister it before the per-namespace state goes away. unregister_key_type() waits for in-flight request_key() calls to drain, so the handler never runs against a freed struct nfs_net. Signed-off-by: Chuck Lever <cel@kernel.org> Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
2026-10-12erofs: reuse superblock for file-backed mountsGiuseppe Scrivano
When the same file-backed image is mounted multiple times (via path or fd) with the superblock_share mount option, reuse the existing superblock instead of creating a new one. This allows multiple mounts of the same image to share in-kernel data structures more efficiently. The backing file is identified by its inode and fsoffset. If mount options conflict or extra devices are used, a separate superblock is created transparently as a fallback. Remount is not allowed on shared superblocks. Tested by mounting a 177M Fedora EROFS image 20 times with full traversal: #!/bin/sh IMG=${1:-/root/fedora.erofs} OPTS=${2:+-o $2} N=20 DIR=$(mktemp -d) trap "umount $DIR/m* 2>/dev/null; rm -rf $DIR" EXIT sync; echo 3 > /proc/sys/vm/drop_caches INODES_BEFORE=$(grep erofs_inode /proc/slabinfo | awk '{print $2}') MEM_BEFORE=$(grep ^Slab: /proc/meminfo | awk '{print $2}') for i in $(seq 1 $N); do mkdir $DIR/m$i mount -t erofs $OPTS "$IMG" $DIR/m$i find $DIR/m$i > /dev/null done echo "Superblocks: $(grep $DIR /proc/self/mountinfo | \ awk '{print $3}' | sort -u | wc -l)" echo "erofs_inode delta: +$(( $(grep erofs_inode /proc/slabinfo | \ awk '{print $2}') - INODES_BEFORE ))" echo "Slab delta: +$(( $(grep ^Slab: /proc/meminfo | \ awk '{print $2}') - MEM_BEFORE )) kB" without superblock_share: # time ./test.sh /root/fedora.erofs Superblocks: 20 erofs_inode delta: +45864 Slab delta: +37448 kB real 0m2.311s user 0m0.222s sys 0m1.998s with superblock_share: # time ./test.sh /root/fedora.erofs superblock_share Superblocks: 1 erofs_inode delta: +2044 Slab delta: +284 kB real 0m0.679s user 0m0.157s sys 0m0.469s The time difference shows that sharing the superblock also benefits the page cache and inode cache, as subsequent mounts of the same image avoid re-reading the backing file. This is particularly useful for container hosts running multiple containers from the same base image. Signed-off-by: Giuseppe Scrivano <giuseppe@scrivano.org> Reviewed-by: Gao Xiang <xiang@kernel.org> Signed-off-by: Gao Xiang <xiang@kernel.org>
2026-10-09Merge tag 'vfs-7.3-rc7.fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs fixes from Christian Brauner: "This contains fixes for the current development cycle. All of them came out of a review of the mount code that started with a bug report. The review modeled the corner cases of mount propagation, unmounting and mount reference counting and turned up a lot of bugs. Most of them years old. Most fixes come with a selftest. - Rework connected mounts. A mount that is unmounted together with its parent can stay attached to the parent to keep its mountpoint covered. That happens when the mountpoint is removed with rmdir(), unlink() or rename(), when a detached tree is dissolved, and for locked mounts in any umount that isn't synchronous, including the teardown of their mount namespace. The parent then owns the child and drops it on its own final mntput(). So any reference from the child's superblock back to one of its ancestors becomes a cycle that is never freed. A loop device backed by an image on a tmpfs and mounted on that same tmpfs is enough. Remove the directory the tmpfs is mounted on from the host, let the container's mount namespace exit, and the loop device, the tmpfs and the filesystem on the loop device are leaked for good. The same works with autofs, zram, ecryptfs, binfmt_misc, fuse passthrough, zloop, a mass storage gadget and md, and the selftests have reproducers for them. This has been possible since v4.1. It is also why "put_mnt_ns(): leave mounts connected" was reverted in -rc5. Keeping every mount of a dying mount namespace connected made these cycles trivial to create. Every unmounted mount is now detached from its parent. Where the mountpoint has to stay covered the mount leaves a cover on the parent instead, allocated together with the mount. A lookup on the unmounted parent that hits a cover finds an empty immutable directory or file on the private nullfs instance. Nothing leads from a cover to another mount, so no unmounted mount owns another one and no cycle can form. This is visible to userspace. A formerly connected mount can no longer be reached through its unmounted parent and ".." inside it leads nowhere, as for every other lazily unmounted mount. With that the private nullfs instance becomes reachable from userspace, so it now refuses mounts on top, is mounted read-only, and refuses fsnotify marks and file locks. Its inodes are shared by every holder and a watch or a lock would otherwise reach across users. may_decode_fh() now also decides its subtree check under a single mount_lock hold, as a racing umount could otherwise let it decode into what a locked child covered. - umount: * Don't silently unmount busy mounts. Since v4.13 propagate_umount() takes down propagated copies of the victim with children as long as each child is an overmount or another copy of the victim, but propagate_mount_busy() only ever checked copies without children or with just an overmount. A container that moved a tree beneath its copy of a host mount lost that tree from under its open file descriptor to a plain umount() on the host. propagate_mount_busy() now applies the same rules, walking each chain of copies once. * Don't let a migrating task hide its reference from umount(). mnt_get_count() sums the per-cpu counters under mount_lock but the mntget() and mntput() fast paths don't take it. A task that takes a reference on a cpu the sum has already passed and drops it after migrating to one the sum hasn't reached yet hides the reference it held to begin with, and umount() succeeds with the file still open. Gets and puts now live in separate per-cpu counters and all puts are summed before all gets with a full barrier in between, the way srcu_readers_active_idx_check() does it. mntget() is unchanged and mntput() gains an smp_wmb(). * Check each submount for references right before unmounting it. shrink_submounts() and mark_mounts_for_expiry() checked all their victims up front. Unmounting the first could move a busy overmount to where the next victim's propagated copy is looked up and it was then unmounted without a check. * Never expire a locked mount. A shrinkable mount moved beneath a locked mount with MOVE_MOUNT_BENEATH takes over the lock, and umount() of an unlocked ancestor expired it and revealed what it covered. That umount() now fails with EBUSY as it does for any other locked child. A lazy umount still takes the whole tree. - Overmounts and locked mounts: * Unhash a dentry before detaching the mounts on it. unlink(), rmdir() and rename() detach the mounts on the victim but only d_delete() it once its inode is unlocked, a window that includes an expedited RCU grace period. In between, a lookup from a mount namespace in which the dentry is a mountpoint found it hashed, positive and uncovered. Drop the dentry first, as d_invalidate() already does. * Don't reveal overmounted entries in refwalk. A refwalk that had grabbed the dentry before the unlink never rechecked it the way rcuwalk does with d_seq and mount_lock. Without any artificial widening three walkers read the covered file 27 times in a minute. step_into() now fails an unhashed dentry marked DCACHE_CANT_MOUNT with -ESTALE and the walk is retried. * Keep covered mounts covered in OPEN_TREE_NAMESPACE. Creating such a mount namespace only takes a user namespace and the copy followed bind mount rules: no children without AT_RECURSIVE and no unbindable mounts with it. An unprivileged user could see what mounts covered in the source, such as the parts of /proc and /sys that container runtimes mask. If the caller doesn't own the source mount namespace a non-recursive copy of a mount with something mounted below the requested directory is now refused and a recursive copy includes unbindable mounts, the way unshare() copies. * Keep the lock on a mount that a propagated copy is moved beneath. MNT_LOCKED moved to any mount that ended up beneath a locked mount, propagated copies included. A host mount and umount on a directory covered by a locked mount in a less privileged mount namespace left that cover unlocked for the namespace's owner to remove. Only mounts the caller places beneath take over the lock now. * Handle mount locking for automounts correctly. Which copies to lock was decided by the mount namespace of the task that triggered the automount. A task in a user namespace that triggered one on a host mount through a file descriptor got the host's own automount locked while its own copy stayed unlocked and could have nosuid, nodev and noexec cleared. Use the owner of the mount namespace the mount lands in. - Use-after-free and crashes: * Refuse an automount below a mount that is in no namespace. The private clones overlayfs uses for its layers have the MNT_NS_INTERNAL error pointer as their namespace, which finish_automount() let through and count_mounts() dereferenced. A fanotify filesystem mark on an overlayfs lower layer hands out file descriptors on such a clone. With debugfs as the lower layer opening "tracing" oopses with namespace_sem held for writing and every mount operation on the system blocks from then on. * Reset the old parent's ->overmount in mnt_change_mountpoint(). When propagate_umount() moved an overmount off a mount that a file descriptor kept alive, MOVE_MOUNT_BENEATH through that descriptor later followed the stale pointer into the freed overmount. * statmount() with STATMOUNT_BY_FD and pivot_root() read the parent of a mount that may be unmounted and only held by a file descriptor, while the parent's final mntput() can free it. statmount() now reads it under mount_lock and pivot_root() first checks that both mounts are in the caller's mount namespace. * Queue a mount only once for mount notifications. A mount reparented by one umount_tree() and taken down by the next under the same namespace_sem hold, as in shrink_submounts(), was queued twice. That cut the mounts queued in between out of notify_list while it still pointed at them, and once they were freed every later mount operation walked freed memory. * Don't let a pseudo dentry become the root of a mount. A bind mount of a bpf token file did that with a DCACHE_NORCU dentry, which is freed without an RCU grace period while lockless path walks may still look at it. Refuse to clone such a mount. * Don't inherit MNT_UMOUNT in clone_mnt(). A bind mount of a lazily unmounted nsfs or pidfs mount through its file descriptor started out flagged as unmounted. Among other things __detach_mounts() then dropped the namespace's reference on it, the mount outlived its namespace and mount_setattr() through the descriptor read the freed namespace. A recursive bind mount of such a mount also copied the unmounted stack still attached to it. That now fails with EINVAL, copying the mount itself still works. * Remove the fsnotify marks of a mount namespace in free_mnt_ns() instead of the RCU callback that frees the namespace, where taking the group mutexes meant sleeping in softirq context. - Propagation and copies: * Keep a copied mount unbindable. Since v6.17 clone_mnt() didn't copy the unbindable flag, so every mount namespace created with CLONE_NEWNS had bindable copies of all unbindable mounts. This had been fixed once before. * Refuse MOVE_MOUNT_SET_GROUP on an unbindable mount. It made the mount an unbindable slave, a state nothing else can produce, or silently dropped the unbindable flag. CRIU applies MS_UNBINDABLE after restoring sharing and isn't affected. * Check a recursive bind mount for mount namespace loops. Recursively bind mounting a tree from another mount namespace could put a mount of a namespace's file inside that same namespace, which then pins itself and all its mounts. Repeating it leaks without limit, the reproducer took Shmem from 380 kB to 65916 kB. The copy is now checked with check_for_nsfs_mounts() before it is grafted, as move_mount() does. * Look at the topmost mount for a mount namespace file. attach_recursive_mnt() never looked at the topmost mount of the source's chain of overmounts. If that was the chain's only mount namespace file an existing mount at a propagated destination got buried below the root of the nsfs file where no path walk reaches it. * Don't put a mountpoint on a dentry that's being removed. attach_recursive_mnt() makes a mountpoint of the source's root without its inode lock, so a racing rmdir() of that directory could leave a mount on it that nothing ever detaches. d_set_mounted() now checks cant_mount() as well. - nullfs: * Take no inode lock for readdir of an immutable directory. The root of every empty mount namespace is the same nullfs directory and iterate_dir() held its i_rwsem across ->iterate_shared(). A reader whose buffer faults on a FUSE mount of its own holds it for as long as its server wants, and with an exclusive locker queued behind it every lookup that misses the dcache, every create and every mount in that directory waits. One user of an empty mount namespace stalls all others. Directories with the new FOP_IMMUTABLE flag skip the lock. * Refuse to reconfigure internal superblocks through fspick(), MS_REMOUNT or the read-only remount that a synchronous umount() of the root does. For nullfs only root in the initial user namespace could do it, but the superblock is shared by every mount namespace and the flags showed up in statfs() for all of them. * Don't update the access time on nullfs and refuse F_SET_RW_HINT on an immutable inode. - unshare: Free an nsproxy that was never installed with nsproxy_free() when set_cred_ucounts() fails. put_nsproxy() dropped active references that were never taken, which triggered a warning and hid the caller's own namespaces from listns(). - Smaller changes: mount_setattr() checks the target before it walks the tree to allocate peer group ids, unshare() puts the old fs_struct before the old namespaces, dissolve_on_fput() drops the file's reference to the tree itself, disconnect_mount() is simplified and the documentation of the propagated unmount rule is brought up to date" * tag 'vfs-7.3-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (58 commits) namespace: simplify disconnect_mount() selftests/filesystems: test covered mounts namespace: rework connected mounts nullfs: add an empty immutable regular file selftests/filesystems: check that reading the root of an empty mount namespace stalls nobody selftests/filesystems: add a helper that holds a readdir in a page fault readdir: take no inode lock on an immutable directory nullfs: refuse file locks fsnotify: let a filesystem refuse marks on its objects namespace: nothing is mounted on or written through knullfs namespace: keep the private nullfs instance in knullfs fhandle: decide the subtree check under mount_lock selftests/filesystems: check that an automount below an overlay layer is refused selftests/filesystems: check the atime of the empty mount namespace root selftests/filesystems: check that a lock lands on the right mount and stays namespace: keep the lock on a mount that a propagated copy is moved beneath namespace: never expire a locked mount nullfs: don't update the access time namespace: handle mount locking for automounts correctly namespace: refuse an automount below a mount that is in no namespace ...
2026-10-08treewide: remove PagePrivate() and PG_private from comments and docsZi Yan
PG_private and PagePrivate() are no longer used. Adjust related comments and documentations to refer to page/folio->private instead. hugetlbfs_reserv.rst is outdated and left unchanged. It should be rewritten. Link: https://lore.kernel.org/20260920-remove-pg_private-v5-16-bb68b6a21869@nvidia.com Signed-off-by: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Assisted-by: LLM Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Alex Markuze <amarkuze@redhat.com> Cc: Viacheslav Dubeyko <slava@dubeyko.com> Cc: Trond Myklebust <trondmy@kernel.org> Cc: Anna Schumaker <anna@kernel.org> Cc: Richard Weinberger <richard@nod.at> Cc: Zhihao Cheng <chengzhihao1@huawei.com> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: "Liam R. Howlett" <liam@infradead.org> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Michal Hocko <mhocko@suse.com>
2026-10-07namespace: rework connected mountsChristian Brauner
UMOUNT_CONNECTED as implemented allows for the creation of reference count cycles. Here's a simple example mkdir /x; mkfifo /ready /go unshare -m sh -c 'mount -t tmpfs tmpfs /x truncate -s 8M /x/img; mkfs.ext4 -q /x/img dev=$(losetup -f --show /x/img) mkdir /x/mp; mount $dev /x/mp echo $dev > /ready; read r < /go' & read dev < /ready rmdir /x echo > /go wait losetup -d $dev losetup -a Take a directory /x on the host, create a new mount namespace, mount a tmpfs on /x, use a file on that tmpfs as the backing file for a loop device, mount that loop device on that tmpfs. Now rmdir /x on the host. This will lazily unmount the mount on top of /x in the container with UMOUNT_CONNECTED. Once the namespace exits nothing references the mount anymore. Now the tmpfs is pinned by the backing file of the loop device and the loop mount is owned by the tmpfs superblock. Fun fact, such cycles can be formed by at least the following subsystems and I have added reproducers for all of them: (1) a loop mount P from an image on a tmpfs next to it, so that P's death shows as the loop device giving up its backing file (2) autofs with a FIFO on P as its pipe, zram with a device node on P as its writeback device, both on a minix image since vfat has neither (3) ecryptfs with its lower directory on P, under a passphrase token added to the session keyring (4) binfmt_misc in a new user namespace with an 'F' interpreter on P (5) a fuse server that answers FUSE_INIT with passthrough on and registers a file on P as a backing file (6) zloop with its zone files in a directory on P (7) a mass storage gadget on the dummy UDC with its LUN file on P, mounted from the SCSI disk the gadget shows up as (8) md with a RAID1 of one loop device and its bitmap file on P, which skips while SET_BITMAP_FILE has no way to succeed (9) rmdir of P's mountpoint from the parent, then the child exits, then the device must be free and LOOP_CLR_FD must release the file The underlying mechanism is UMOUNT_CONNECTED (MNT_LOCKED falls into the same class). With UMOUNT_CONNECTED an unmounted mount stays attached to its parent. This is used to protect revealing the underlying mount and is a non-negotiable security mechanism. So now the parent owns that mount and is put on the parent's final mntput(). That moves it to mnt_stuck_children and ultimately it's cleaned up by cleanup_mnt(). The fact that ownership of the child mount gets transferred to the parent turns every reference from a child's superblock back to one of its ancestors into a cycle. Don't keep the child attached at all. What the parent needs is that a lookup at the child's mountpoint keeps finding some mount, not the child itself and it's not a guarantee we have given really. When an unmounted mount would have stayed attached to its unmounted parent disconnect it like every other unmounted mount and leave a marker behind. A lookup on the parent that misses the mount hash and hits a marker finds knullfs. Either a file or a directory. Nothing leads from a marker to any other mount. The marker is owned by the parent and dropped by the parent's final mntput() or by __detach_mounts() when the mountpoint is deleted from under it. It is allocated together with the mount. With that every unmounted mount is a root and holds only its own reference which namespace_unlock() drops. No unmounted mount owns another one. A superblock that pins an ancestor can't form a cycle. It has a visible change. Mounts left connected (rmdir etc.) used to stay traversable through the parent for as long as something held the parent. Now it is detached with the umount. It lives as long as something references it but it isn't reachable through the parent anymore and ".." inside it leads nowhere which is the same as for every other lazily unmounted mount. Link: https://gist.github.com/mvo5/63ef46482349f3b1c3957d463a0c9c6f Link: https://patch.msgid.link/20261002-work-mount-cover-v1-2-232a8f52b43c@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-10-06netfs: Document the remote size member and its accessorsKarl Mehltretter
netfs_inode.remote_i_size was renamed to _remote_i_size and accessors were added to prevent torn accesses. The netfs library documentation still shows the old member name. Update the struct excerpt and member description. Direct readers to netfs_read_remote_i_size() and netfs_write_remote_i_size(), and state that writes require inode->i_lock. Fixes: 2c8f4742bb76 ("netfs: Fix potential for tearing in ->remote_i_size and ->zero_point") Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com> Link: https://patch.msgid.link/20260912073444.51152-1-kmehltretter@gmail.com Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-10-06efivarfs: add nostatfs mount option to skip QueryVariableInfo()Prashant Singh
QueryVariableInfo() is an EFI runtime service that, on some firmware, takes tens of milliseconds and runs with preemption disabled, stalling the CPU that services it (and, on firmware that services it via SMM, all CPUs). efivarfs_statfs() calls it (rate-limited since commit b2326338dc68 ("efivarfs: Rate limit statfs() handler")) to report the variable-store used/available capacity, so any statfs(2) -- e.g. every "df" -- can inject that stall into unrelated latency-sensitive workloads. Add a negatable "nostatfs" mount option: with nostatfs, statfs(2) skips QueryVariableInfo() and reports zero used/available; with statfs it reports the capacity as before. It defaults to nostatfs on CONFIG_PREEMPT_RT so real-time kernels do not take the stall out of the box, but statfs can be passed there to force reporting back on -- e.g. for tools such as fwupd that need the efivars free space to update Secure Boot key databases. The option can also be toggled on a live mount via remount, so reporting can be enabled only for the duration of a firmware update without unmounting the boot-time efivarfs mount: mount -o remount,statfs /sys/firmware/efi/efivars # reporting on mount -o remount,nostatfs /sys/firmware/efi/efivars # reporting off A remount that does not specify statfs/nostatfs keeps the current setting. Tested on an Intel Xeon E5-2628L v4, 6.12 kernel: a default statfs(2) takes ~66 ms (the firmware call), versus ~11 us with nostatfs. Suggested-by: Ard Biesheuvel <ardb@kernel.org> Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Prashant Singh <singhpra@juniper.net> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2026-10-05xfarray: don't allow users to unset in the middle of an arrayDarrick J. Wong
Now that we've merged online repair and removed some clunky parts of the original online checking code, the only user of xfarray_unset is the free space btree repair code, and it only needs to be able to remove records from the end of the array. Let's remove all the code that handles "unset" array elements that are not at the end, because we can just reduce the array element count. Remove the "store anywhere" function because it was only ever used by the callers who used unset to remove elements in the middle of the array. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-09-30netfs: clear post-EOF pagecache when extending a file via writePaulo Alcantara
Fix netfs to erase the contents of a hole created after the EOF by an ordinary write if dirty data has been previously left there by writes through an mmapped region. Neither the buffered nor the unbuffered/DIO write path clears that stale pagecache. Zero the tail of the folio straddling the EOF before an extending write. That is the only folio that can hold data written past the EOF through an mmap, as pages wholly beyond the EOF can't be faulted in. The folio is zeroed rather than dropped so a concurrent extending write can't lose data. Both write paths downgrade the i_rwsem to shared, so extending writes can run concurrently and the i_size read by the caller may be stale by the time the folio is locked. Re-read i_size under the folio lock and clamp the zeroed range up to it, so a racing write that already put data into the folio isn't clobbered. Wait for any writeback on the folio to finish before zeroing it so that the pagecache isn't modified while it may still be read by the transport during transmission. Honour IOCB_NOWAIT by returning -EAGAIN rather than blocking on the folio lock, on writeback, or in folio_mkclean()'s rmap walk when the folio is mapped. truncate_pagecache() can't be used here: it must be called with the i_rwsem held exclusively, but these write paths only hold it shared, and it would block unconditionally, breaking IOCB_NOWAIT. Callers that hold i_rwsem exclusively for the whole resize (truncate, setattr, fallocate, clone) exclude any genuine concurrent buffered writer, so staleness can instead be decided from the folio's dirty state, as pagecache_isize_extended() already does for filesystems that serialise writes against truncate/setattr via a single i_rwsem. Export netfs_clear_stale_post_isize() helper to handle such case. The helper is required by the CIFS client to fix generic/363. Closes: https://sashiko.dev/#/patchset/20260921230755.1133425-1-pc%40manguebit.org Fixes: 938e13a73b24 ("netfs: Implement buffered write API") Fixes: 153a9961b551 ("netfs: Implement unbuffered/DIO write support") Reviewed-by: David Howells <dhowells@redhat.com> Reviewed-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Paulo Alcantara <pc@manguebit.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com> Cc: Shyam Prasad N <sprasad@microsoft.com> Cc: Tom Talpey <tom@talpey.com> Cc: Bharath SM <bharathsm@microsoft.com> Cc: stable@vger.kernel.org
2026-09-29kbuild: Move gen_init_cpio and gen_initramfs.sh to scripts/Nicolas Schier
gen_init_cpio and gen_initramfs.sh are part of kbuild and required for all kernel builds w/ CONFIG_BLK_DEV_INITRD. Move both to scripts/ to be more clear about their importance. Link: https://lore.kernel.org/all/aSdrCFkUQup3qb-q@derry.ads.avm.de/ Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Nicolas Schier <nsc@kernel.org> Link: https://patch.msgid.link/20260928-move-gen_init_cpio-to-scripts-v4-2-f437a33c40ac@kernel.org Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2026-09-25x86/resctrl: Update documented unit for the "activity" eventTony Luck
The unit for the AET (Application Energy Telemetry) activity event[1] is nF, not F, see https://github.com/intel/Intel-PMT/blob/main/xml/CWF/OOBMSM/RMID-ENERGY/cwf_common.xml#L9 Fixes: a8848c4b43ad ("x86,fs/resctrl: Update documentation for telemetry events") Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://patch.msgid.link/20260915190431.18189-1-tony.luck@intel.com
2026-09-25docs: update the unmount propagation ruleChristian Brauner
Section 5f still describes the rule propagate_umount() used before commit f0d0ba19985d ("Rewrite of propagate_umount()"). It states that a mount that receives the unmount by propagation is left alone as soon as it has any submount. That's not true anymore. A propagated unmount unmounts a mount with sub-mounts as long as every sub-mount gets unmounted together with it. This is the case when the sub-mounts are unmounted by the same propagation. Only a sub-mount that cannot be unmounted keeps its parent mounted. The section also only describes a single mount without sub-mounts. But lazy unmounts take a tree and every mount of the tree propagates its unmount from its parent mount. Link: https://patch.msgid.link/20260923-work-mount-fixes-v1-8-f424cf8d3242@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-25VFS: enhance d_splice_alias() to handle hashed dentriesNeilBrown
We currently have three interfaces for attaching existing inodes to normal filesystems(*). - d_add() requires an unhashed or in-lookup dentry and doesn't handle splicing in case a directory already has dentry - d_instantiate() requires a hashed dentry, and also doesn't handle splicing. - d_splice_alias() requires unhashed or in-lookup and does handle splicing, and can return an alternate dentry. So there is no interface that supports both hashed and in-lookup, which is what ->atomic_open needs to deal with. Some filesystems check for in-lookup in their atomic_open and if found, perform a ->lookup and can subsequently use d_instantiate() if the dentry is still negative. Others d_drop() the dentry so they can use d_splice_alias(). This last will cause a problem for proposed changes to locking which require the dentry to remain hashed while an operation proceeds on it. There is also no interface which splices a directory (which might already have a dentry) to a hashed dentry. Filesystems which need to do this d_drop() first. Some filesystems (NFS) skip ->lookup processing for LOOKUP_CREATE|LOOKUP_EXCL which includes mknod, link, symlink etc. So these inode operations might get an unhashed or a hashed-negative dentry. There is no interface for instantiating these so again they need to unhash first (nfs_link) So with this patch d_splice_alias() can handle hashed, unhashed, or in-lookup dentries. This makes it suitable for ->lookup, ->atomic_open, and ->mkdir as well as others. As a side effect d_add() will also now handle hashed dentries, but I have plans to remove d_add() as there is no benefit having it as well as the others. Once updated to handle nr_dentry_negative as is required for hashed dentrties, __d_add() contains code that is identical to __d_instantiate(), so the former is changed to call the later so now: - d_add() calls __d_add() which hashes and might call __d_instantiate. - d_instantiate() calls __d_instantiate() with appropriate locks. It was suggested by Al Viro https://lore.kernel.org/all/20250813050717.GD222315@ZenIV/ that rather than allow d_splice_alias() to handle both hashed and unhashed, we should have a new d_splice_alias_hashed(). I chose not to follow this path because, as noted above, there are several cases where the filesystem has no a priori knowledge of the state of the dentry, and so would need if (d_unhashed(dentry)) alias = d_splice_alias(inode, dentry); else alias = d_splice_alias_hashed(inode, dentry); which is clumsy. Also I hope to minimise the distinction between hashed and in-lookup (they will both be hashed, just with different DCACHE_ENTRY_TYPE) and reduce the use of unhashed dentries. Unhashed dentries would only be created by d_alloc_name() and all of those are passed to d_make_persistent() (though configfs passes some to d_add(dentry, NULL) first!). So the use-case for d_splice_alias() on unhashed dentries would disappear. Note that d_make_persistent() already handles both hashed and unhashed dentries - just not in-lookup. * There is also d_make_persistent() for filesystems which are dcache-based and don't support mkdir, create etc, and d_instantiate_new() for newly created inodes that are still locked. Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260904215142.1060510-3-neilb@ownmail.net Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-25VFS: fix various typos in documentation for start_creating start_removing etcNeilBrown
Various typos fixes. start_creating_dentry() now documented as *creating*, not *removing* the entry. Unwanted spaces in Documentation/filesystems/porting.rst removed. Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260904215142.1060510-2-neilb@ownmail.net Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>