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13 daysMerge tag 'mm-stable-2026-08-26-15-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff" (Lorenzo Stoakes) Index MAP_PRIVATE file-backed folios by their anonymous page offset to resolve confusion around reverse mapping for zeroed and CoW'd file-backed memory. Use this new VMA anonymous page offset tracking to eliminate index conflicts and lay the foundation for scalable CoW performance improvements. - "promote mapped executable folios after first usage for MGLRU" (Baolin Wang) Make MGLRU's protection of mapped executable file folios more reliable. Follow the classical LRU's logic, promoting mapped executable file folios after their first usage to give executable code a better chance to stay in memory and improve workload performance. - "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong Chen) Fix per-node proactive reclaim interface's ignoring the swappiness parameter when CONFIG_MEMCG is disabled by consolidating sc_swappiness() into a single function that checks proactive_swappiness regardless of kernel configuration. - "mm/vmscan: reduce lru_lock contention via vmstat-derived scan-balance cost" (Usama Arif) Reduce lru_lock contention in the reclaim path by deriving scan-balance costs from vmstat counters rather than lock-acquired producer updates. Read and decay these cost signals on the reclaim side under a dedicated per-lruvec lock, reducing total LRU lock wait time by over 60% without impacting scan throughput. - "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky) Fix two low-risk zram bugs which Sashiko spotted in drive-by review. - "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's memcg" (Zi Yan) Fix xas_split_alloc() by enabling target folio memcg charging during splits and adding the missing __GFP_ACCOUNT flag for proper XArray node memory accounting. - "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick) Replace hardcoded binary names in selftests/mm/.gitignore with a generic pattern-matching rule to automatically ignore generated test files and avoid manual updates when adding new tests. - "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon) Make the incompatibility between FLATMEM and NUMA explicit in mm/Kconfig and remove the unused pgdat_page_ext_init() function. - "zram: fix zstd error paths and add parameter validation" (Haoqin Huang) Clean up zram compression backends by removing redundant error cleanup, adding parameter and dictionary validation, auto-prefixing algorithm error logs, and resetting parameters prior to reinitialization. - "zram: fix stale scan bounds after reinitialization" (Longlong Xia) Prevent out-of-bounds slot accesses during concurrent zram resets by moving table scan bound calculations under dev_lock in writeback_store() and read_block_state(). - "add anon mTHP collapse test cases" (Baolin Wang) Extend selftests helper functions to support arbitrary page orders and add new test cases and options for mTHP collapse in khugepaged. - "selftests/mm: Handle unsupported and transient test conditions" (Muhammad Usama Anjum) Update MM selftests to report a SKIP status instead of a failure when required kernel or filesystem features are unsupported, while adding retry logic for transient page migration errors. - "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia) Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled and extend shrink_memcg() to support batch writeback for improved writeback efficiency. - "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren Baghdasaryan) Introduce an IOCTL-based binary interface for memory allocation profiling that enables kernel-side filtering before per-CPU counter aggregation. This eliminates the text-parsing overhead of /proc/allocinfo and provides up to a 20x speedup by transferring only filtered allocation data to userspace. - "better block swap batching and a different take on swap_ops v5" (Christoph Hellwig) Refactor block swap I/O to use swap_iocb for batching instead of single-bio requests and rebase the swap_ops interface, achieving faster swap throughput during kernel builds. - "mm: kmemleak: reduce transient false positives by confirming leaks" (Catalin Marinas) Reduce false-positive kmemleak reports by combining two kmemleak enhancements that add a second confirmation scan and a configurable minimum unreferenced scan count module parameter. - "mm: kmemleak: default min_unref_scans to 2 for verbose kernels" (Breno Leitao) Auto-scanning kernels can generate false-positive memory leak reports on single scans, so this patch defaults min_unref_scans to 2 when CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second confirming scan. - "swap_ops updates" (Christoph Hellwig) Batching I/O for synchronous swap devices causes performance regressions and filesystem-based swap suffers from double-indirection overhead. This series resolves both issues by reintroducing per-folio writes for synchronous swap and allowing filesystems to directly export their own swap_ops. - "mm/khugepaged: several cleanups" (Nico Pache) khugepaged accumulated redundant state-checking patterns and outdated comments following mTHP integration. Introduce dedicated helpers for PTE validation and event counting while refreshing the internal documentation. - "maple_tree: lock checking and clean ups" (Liam Howlett) Syzbot reports incorrectly blame memory management exit paths for locking bugs, maple tree erase operations risk allocation failures without gfp flags and internal documentation lacks clarity. Improve lock error detection, update docs, fix race and allocation edge cases and optimize erase allocations using a fallback to GFP_KERNEL | GFP_NOFAIL. * tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (172 commits) selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC memcg: move LRU size accounting on reparenting instead of copying it mm/vmscan: fix comment logic in balance_pgdat maple_tree: add helper mas_make_walkable() maple_tree: avoid extra gap calculation maple_tree: fix argument name in header maple_tree: change two GFP flags in tests maple_tree: document erase and allocations better maple_tree: avoid mas_erase() and mtree_erase() failures maple_tree: document that erase may use GFP_KERNEL for allocations maple_tree: catch race in mas_alloc_cyclic() maple_tree: add bulk parent set helper maple_tree: micro optimisation of mas_wr_store_type() maple_tree: optimise mas_wr_node_store() when not in rcu mode maple_tree: use prefetched value in mas_wr_store_type() maple_tree: clarify comments on mas_nomem() maple_tree: drop MAPLE_ALLOC_SLOTS maple_tree: drop dead code from mas_extend_spanning_null() maple_tree: documentation fix maple_tree: add write lock checking with lockdep sequence numbers ...
2026-08-24mm: Documentation: clarify where the mTHP stats liveNico Pache (Red Hat)
The note about khugepaged counters references /proc/vmstat for the PMD case, but never mentions where the mTHPs stats can be found (i.e.: /sys/kernel/mm/transparent_hugepage/hugepages-<size>kB/stats/) Add a small addition to this section for clarity. Also fix a missing period while we are at it. Link: https://lore.kernel.org/20260811-khugepaged_pte_refactor-v4-7-ddac39d61c4a@linux.dev Signed-off-by: Nico Pache (Red Hat) <nico.pache@linux.dev> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Suggested-by: Lorenzo Stoakes <ljs@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Acked-by: Pedro Falcato <pfalcato@suse.de> Reviewed-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Reviewed-by: Lance Yang <lance.yang@linux.dev> Cc: Barry Song <baohua@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usama.arif@linux.dev> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-20Merge tag 'mm-stable-2026-08-18-18-39' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "mm: drop "sub" prefix from various places" (Dev Jain) page->folio conversion and a naming cleanup - "mm/kasan: remove redundant initialization for kasan_flag_write_only" (Igor Putko) KASAN cleanup work - "mm/filemap: reduce unnecessary xarray lookups" (Chi Zhiling) Small speedup in the pagecaache read code - "mm/percpu: Fix possible NOFS/NOIO reclaim recursion" (Kaitao Cheng) Improve the vmalloc code - mainly the avoidance of GFP_KERNEL allocations when the caller asked for GFP_NOFS or GFP_NOIO - "mm/kmemleak: avoid soft lockup when scanning task stacks" (Breno Leitao) Avoid a soft lockup watchdog trigger from the kmemleak scanning code in extreme situations - "mm/page_owner: misc cleanups" (Ye Liu) Cleanups to the page_owner code. For some reason lots of people have been working on the page_owner code this cycle. - "mm: convert to walk_page_range_vma() to eliminate find_vma()" (Kefeng Wang) Simplify and accelerate the page walking library function - "mm/migrate: preparatory cleanups for batch copy and offload" (Shivank Garg) Cleanups in the migration code - "mm/page_owner: add per-fd filter infrastructure for print_mode and NUMA filtering" (Zhen Ni) Per-fd filtering to page_owner in order to reduce the sometimes vast amount of output it can produce - "mm: Refactor bootmem gigantic hugepage allocation" (Muchun Song) Fixes and preparatory cleanups around bootmem HugeTLB handling, sparse initialization ordering, and related vmemmap setup - "mm/zsmalloc: reduce lock contention in zs_free()" (Wenchao Hao) Reduce lock contention in zs_free(), which dominates the unmap path under memory pressure on Android (LMK kills) and on x86 servers running zswap-heavy workloads. Up to 1.83x improvement in microbenchmarking. - "move alloc_tag.c file under mm/" (Suren Baghdasaryan) - "samples/damon: handle damon_{start,stop}() failures" (SJ Park) Fix improper handling of damon_start(), damon_stop(), and damon_call() failures across DAMON sample modules to prevent potential memory leaks, operation disruptions and use-after-free bugs - "mm/damon/sysfs: kobject_del() directories that users can create/remove" (SJ Park) Fix delayed sysfs directory removal under DEBUG_KOBJECT_RELEASE causeing creation failures due to duplicate directory names by adding missing kobject_del() calls before creating new directories - "mm: cleanup clear_not_present_full_ptes()" (David Hildenbrand) Clean up the core pte handling code - "selftests/damon: misc fixes for test bugs" (Kunwu Chan) Fix several bugs in the DAMON selftests - "selftests/damon: fix memcg_path staging handling" (Cheng Nie) Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and add a test case for it in sysfs.py. - "selftests/damon: test kdamond refresh_ms" (Ruslan Valiyev) Selftest coverage for DAMON's refresh_ms sysfs feature by updating the test control module and verifying that scheme stats update automatically without manual intervention - "mm/damon: five misc fixups" (Akinobu Mita) Miscellaneous DAMON fixups. - "mm/damon/core: detect internal variation above max_nr_regions/2" (Jiayuan Chen) Fix DAMON's region splitting behavior when region counts exceed half the maximum budget by dynamically scaling down the split fraction as the limit approaches, preventing large regions from staying un-split, and add corresponding KUnit test coverage - "mm: preparatory patches for PMD level swap entries" (Usama Arif) Refactor and clean up PMD softleaf helpers, call sites, and architecture flags to lay the groundwork for a follow-up series that introduces PMD page table swap entries - "mm/damon: update, optimize, and clean up doc, tests, and code" (SJ Park) Update DAMON design and ABI documentation, expands unit and selftest coverage, optimize damon_commit_target_regions(), and clean up recently added sysfs interface code for better readability - "mm/vmpressure: reduce CPU, memory and code overhead on cgroup v2" (Usama Arif) Optimize vmpressure() by skipping unnecessary work on cgroup v2 for userspace event notifications and refactor v1-only eventfd handling into mm/memcontrol-v1.c to reduce memory overhead and code complexity - "selftests/mm: refactor pkey helpers and fix mmap error handling" (Hongfu Li) Refactor pkeys shared tracing and assertion helpers into a common file, unify protection key selftests to use consistent diagnostic logging and assertions, and enforce standardized MAP_FAILED return checks for mmap() calls across the tests - "mm/damon: optimize out nr_accesses_bp" (SJ Park) Replace the error-prone, continuously updated nr_accesses_bp field in damon_region with an on-demand moving sum function, reducing structure memory overhead and avoiding state corruption bugs - "Open HugeTLB allocation routine for more generic use" (Ackerley Tng) Decouple HugeTLB folio allocation from VMA dependencies by introducing hugetlb_alloc_folio(), enabling subsystems like guest_memfd to allocate HugeTLB folios without standard VMA reservations or pseudo-VMAs - "mm/damon: provide pseudo moving sum probe_hits" (SJ Park) Integrate DAMON's probe_hits attribute counter into the pseudo moving sum infrastructure, enabling real-time, online monitoring without waiting for full aggregation intervals - "mm: Some cleanups for page allocator APIs" (Brendan Jackman) Simplify and refactor the page allocator entry points and flags by unifying allocation paths, adding internal alloc_flags arguments, and eliminating redundant __ prefixed alloc_pages variants. - "Fix incorrect access of hugetlb pte entries" (Dev Jain) Enforce the consistent use of huge_ptep_get() instead of ptep_get() for HugeTLB entries and fixes an unaligned address issue in arm64's huge_ptep_get() implementation - "mm/damon: validate all parameters in the core" (SJ Park) Consolidate parameter validation into the DAMON core specifically within damon_start() and damon_commit_ctx() to centralize error checking, eliminate caller-side redundant checks and to improve maintenance efficiency - "tools/mm/page_owner_sort: fix filtering and cleanup issues" (Yichong Chen) Rename is_need() to filter_record() for clearer return semantics, fix per-record allocation memory leaks and bound output copies in search_pattern() to address an existing buffer issue - "memcg: bail out reclaim when memcg is dying" (Jiayuan Chen) Mitigate a system-wide stall which occurs when a cgroup is removed while one of its memory control files is doing synchronous reclaim - "mm/memory-failure: add panic option for unrecoverable pages" (Breno Leitao) Introduce an opt-in vm.panic_on_unrecoverable_memory_failure sysctl that immediately panics the kernel on unrecoverable memory errors in kernel-owned pages to preserve error context and prevent delayed, silent data corruption - "mm/damon: refactor damon_{start,stop,commit}() for simple error handling" (SJ Park) Refactor the DAMON core API functions to guarantee that all contexts are fully stopped when damon_start(), damon_stop(), or damon_commit() fail, eliminating the need for complex and error-prone caller-side cleanup code - "Keep tail page private zero at free and folio split" (Zi Yan) Add checks to ensure tail_page->private is zero when freeing compound or high-order pages and when promoting tail pages during large folio splits. By validating these fields at free and split time, it allows the removal of redundant private field clearing inside prep_compound_tail() - "mm: drop redundant lru_add_drain in anon folio reuse paths" (Barry Song) Eliminate redundant lru_add_drain() calls in wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock contention and system overhead By validating folio refcounts against the LRU cache before draining and removing unnecessary drains in the swap path, it achieves up to a 30.5% reduction in drain calls during heavy swap workloads - "mm: clean up folio LRU and swap declarations" (Jianyue Wu) Reorganize folio LRU and swap code by relocating page-cluster state to mm/swap_state.c, renaming mm/swap.c to mm/folio.c, and moving MM-internal reclaim declarations into mm/internal.h. - "userfaultfd: working set tracking for VM guest memory" (Kiryl Shutsemau) Add userfaultfd support for tracking the working set of VM guest memory, so a VMM can identify hot pages and reclaim cold ones to tiered or remote storage - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 2)" (David Hildenbrand) Remove the remaining pieces of CONFIG_HAVE_BOOTMEM_INFO_NODE, performing some smaller cleanups around freeing of reserved vmemmap pages on the way. - "mm/damon: update probe hits for runtime parameter commits" (SJ Park) Ensure that DAMON's probe_hits attribute counter is properly updated when monitoring intervals are changed at runtime, matching the behavior of nr_accesses. To achieve this, it refactors and renames existing helper functions for shared use, applies the updates to probe_hits, and handles edge cases in damon_probe_hits_mvsum() to maintain measurement accuracy. - "KSM: performance optimizations for rmap_walk_ksm" (xu xin) Resolve a severe KSM reverse-mapping performance bottleneck where thousands of split VMAs sharing a single anon_vma cause extended lock contention. By adding an interval-filtering check during the rmap walk, it reduces worst-case anon_vma lock hold times from over 500ms down to under 2ms, preventing application freezes and latency spikes under memory pressure. - "mm: split a couple of headers from internal.h" (Mike Rapoport) Split declarations related to mm_init, memblock, vmalloc and sparse into new headers - "KSM: use linear_page_index in collect_procs_ksm()" (xu xin) Apply the interval tree optimization from rmap_walk_ksm() to collect_procs_ksm() to avoid iterating over non-matching VMAs during KSM memory error handling. It hoists loop-invariant address initialization and restricts the anon_vma_interval_tree_foreach walk to a targeted page offset range, reducing redundant checks and improving lookup efficiency. - "selftests/mm: avoid false failures in hugetlb and KSM tests" (Sayali Patil) Fix issues in the hugetlb and KSM MM selftest categories that can report failures when the prerequisites for the tests are not satisfied - "mm/damon: introduce data attributes only monitoring" (SJ Park) Introduce attribute-weighted region management in DAMON, allowing users to prioritize specific data attributes (such as page sizes or cgroups) over or instead of access monitoring. By assigning weights to attribute probes, DAMON can completely disable access tracking and adjust monitoring regions based on weighted probe-hit counters to optimize monitoring quality for attribute-focused workloads. - "mm/hmm: Add mmap lock-drop support for userfaultfd-backed mappings" (Stanislav Kinsburskii) Extend hmm_range_fault() to support userfaultfd-backed regions by allowing the mmap lock to be dropped during fault handling via a new hmm_range_fault_locked() helper. By accepting a locked pointer and signaling retry status when lock release occurs, it enables page fault resolution in userfaultfd regions while preserving backward compatibility for existing callers. - "mm: make VMA page offset handling more consistent" (Lorenzo Stoakes) Clean up and standardize how vma->vm_pgoff is accessed and manipulated across file-backed and anonymous mappings in the kernel It introduces dedicated helper functions such as vma_start_pgoff(), vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while renaming rmap interval tree helpers to better reflect their functionality. These changes establish a cleaner foundation for future work that will unify virtual page offset indexing for all anonymous and CoW'd folios. - "mm: handle device-private PMDs in walk callbacks" (Usama Arif) Address kernel panics and state corruption caused by MM walk callbacks reaching non-present device-private PMD swap entries created during HMM migrations It ensures that functions which acquire pmd_trans_huge_lock() properly recognize device-private PMDs instead of assuming a present THP or a standard migration entry. - "mm/rmap: Refactor try_to_unmap_one" (Dev Jain) Refactor try_to_unmap_one by modularizing Hugetlb, anonymous-lazyfree, and anonymous-swapbacked logic into dedicated functions, laying the structural groundwork for batched anonymous large folio unmapping. - "Docs/ABI/damon: sysfs ABI document fixes and additions" (Song Hu) Fix typos and fills in missing entries in the DAMON sysfs ABI document - "dax/kmem: atomic whole-device hotplug via sysfs" (Gregory Price) Introduce an atomic sysfs state attribute and supporting DAX/MM infrastructure to prevent userland races when offlining and removing entire memory regions By adding an unplugged state alongside standard online modes, it enables whole-device atomic hotplug control while preserving backward compatibility. - "mm: convert more vm_flags_t users to vma_flags_t" (Lorenzo Stoakes) Continue transitioning the kernel from the deprecated vm_flags_t type to vma_flags_t across core memory management infrastructure. It replaces legacy type usage in core functions such as do_mmap(), unmapped area allocation, mm->def_vma_flags, and VMA operations like mlock, mprotect, and mremap. - "Two small patches to clean up mm/mm_slot.h" (xu xin) Refactor mm_slot.h by introducing mm_slot_remove() to unify duplicate slot deletion sequences in khugepaged and KSM. It also adds code documentation explaining why mm_slot_lookup and mm_slot_insert must remain as preprocessor macros rather than static inline functions. - "mm/damon/core: hide core-private struct fields" (SJ Park) Clean up DAMON core structures by consistently marking internal-only fields with private: comment tags to prevent improper direct access from outer layers. It enforces encapsulation across core structures including damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to interact through approved access APIs instead of exposing raw struct members. - "mm/damon: unurgent fixes for infinite loop, NULL de-ref and races" (SJ Park) Address potential infinite loops, NULL dereferences, and race conditions identified in DAMON It fixes an infinite loop triggered by extreme user configurations, a NULL pointer dereference within unit tests and minor monitoring accuracy degradation caused by subtle runtime races. - "mm/page_alloc: fixes for free_pages_nolock() on RT/UP" (Brendan Jackman) Fix an NMI safety flaw in __free_frozen_pages() where freeing pages on non-SMP or PREEMPT_RT kernels can bypass can_spin_trylock() checks via non-PCP or isolated migration paths. It also resolves potential kernel crashes and privilege escalation risks triggered when BPF tracing runs in NMI context alongside memory hotplug or large allocation frees. - "mm/page_alloc: couple of followups for recent cleanups" (Brendan Jackman) Clean up and update page allocator nomenclature, documentation, and debug assertions. It aligns internal FPI_ flags with the public "nolock" naming convention, removes outdated internal implementation details from high-level page allocator comments, and eliminates obsolete VM_BUG_ON() assertions in allocation paths. - "mm/mseal: further cleanups" (Lorenzo Stoakes) Refactor and simplify the mseal implementation by clarifying API boundaries and removing unnecessary code complexity. It replaces generic do_mseal() usage outside the syscall with a dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO, eliminates mm_struct parameters to enforce that sealing applies only to current->mm, and streamlines overall logic and comments with no functional changes intended. - "mm/vmscan: fix swappiness=max and clean up per-node proactive reclaim" (Ridong Chen) Resolve reclaim behavior bugs and clean up function parameters across memory reclaim paths It fixes swappiness=max in both standard reclaim and MGLRU so unswappable anonymous memory no longer falls back to evicting page cache, ensures reclaim_store() returns accurate error codes instead of collapsing all failures into -EAGAIN, and removes the obsolete gfp_mask parameter from __node_reclaim(). - "mm: mincore: misc cleanups" (Kefeng Wang) Clean up and simplifies the mincore code. Most importantly, it removes the historical special behavior that always reports VM_PFNMAP pages as non-resident. - "mm/huge_memory: drop dead split helper variants" (Kiryl Shutsemau) Two trivial cleanups in the folio split API - "mm/damon: fix uninitialized DAMOS field and kunit exec expectation bugs" (SJ Park) Resolve minor operational and testing bugs in DAMON identified by Sashiko. It initializes the damos->last_applied field to prevent occasional efficiency degradation and fixes invalid memory accesses in DAMON KUnit tests during test failure handling. - "cleanup for stable_page_flags()" (Jinjiang Tu) Clean up and refactor stable_page_flags() used by /proc/kpageflags without altering functionality. It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag bits, converts folio-specific flag checks to standard folio_test_*() helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling. - "Batch unmap of uffd-wp file folios" (Dev Jain) Extend batched folio unmapping support to file folios within userfaultfd write-protect (uffd-wp) VMAs by adding batching capabilities to pte_install_uffd_wp_if_needed(). This removes special-case restrictions on uffd-wp VMAs in try_to_unmap_one(), significantly simplifying the function's control flow and complexity. - "mm/early_ioremap: clarify and clean up early_ioremap_reset()" (Sang-Heon Jeon) Clarify and clean up the architecture-specific usage of __late_set_fixmap() and __late_clear_fixmap() after early_ioremap_reset() It adds explicit documentation regarding when early_ioremap_reset() must be called and removes redundant macro definitions and reset calls in the RISC-V and ARM64 architectures. - "mm: fix reclaim storms in defrag_mode" (Johannes Weiner) Address severe performance regressions, swap storms, and spurious OOMs caused by vm.defrag_mode=1 under high memory pressure in Meta production It updates the page allocator slowpath so non-movable allocation requests actively trigger direct reclaim and direct compaction at pageblock_order scale, allowing them to claim whole pageblocks rather than spinning unproductively. - "zram: lockmap tweaks" (Sebastian Siewior) Optimize and fix lockdep tracking for zram devices by consolidating per-entry lockmaps and isolate lock classes across multiple instances This reduces memory overhead by replacing per-entry lockdep_map instances with a single map per struct zram, and assigns a dynamic lock_class_key to each instance to prevent false deadlock reports when different zram devices are backed by distinct filesystems. * tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (501 commits) selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check selftests/mm: unpoison pages in memory-failure teardown mm/shmem: downgrade final i_blocks check in shmem_evict_inode() to pr_warn() mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro mm/zsmalloc: fix release order of locks in zs_page_migrate() Documentation: zram: remove sections numbering ksm: stop iterating VMAs when ksm_test_exit returns true mm: fold userfaultfd_rwp() to false without CONFIG_ARCH_HAS_PTE_PROTNONE mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() zram: use a custom key for each zram object zram: move lockmap to be per-zram instead per table selftests/mm: fix gup_longterm EINVAL error message mm: page_alloc: fix non-movable reclaim storm in defrag_mode mm: page_alloc: move capture_control to the page allocator mm: compaction: support non-movable compaction for pageblock requests mm: page_alloc: __GFP_FS lockdep annotation for direct compaction hugetlb: evaluate subpool free state while locked mm/damon: remove trailing semicolons after function definitions mm/damon/ops-common: prevent migration fallback to non-target nodes mm/damon: update outdated comment about DAMOS filter handling ...
2026-08-04Docs/admin-guide/mm/damon/usage: document weight sysfs fileSJ Park
Update DAMON usage document for newly added probe weight file. Link: https://lore.kernel.org/20260710134651.18084-19-sj@kernel.org Signed-off-by: SJ Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04Documentation/userfaultfd: document RWP working set trackingKiryl Shutsemau (Meta)
Add an admin-guide section covering UFFDIO_REGISTER_MODE_RWP: - sync and async fault models; - UFFDIO_RWPROTECT semantics; - UFFD_FEATURE_RWP_ASYNC; - UFFDIO_SET_MODE runtime mode flips. It also covers typical VMM working-set-tracking workflow from detection loop through sync-mode eviction and back to async. Link: https://lore.kernel.org/20260708111417.173443-16-kirill@shutemov.name Signed-off-by: Kiryl Shutsemau <kas@kernel.org> Assisted-by: Claude:claude-opus-4-6 Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Hildenbrand <david@kernel.org> Cc: James Houghton <jthoughton@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: SeongJae Park <sj@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Cc: kernel test robot <lkp@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04mm/pagemap: add PAGE_IS_ACCESSED for RWP trackingKiryl Shutsemau (Meta)
PAGEMAP_SCAN already reports PAGE_IS_WRITTEN from the inverted uffd PTE bit, targeting the UFFDIO_WRITEPROTECT workflow. UFFDIO_RWPROTECT reuses the same PTE bit as a marker for read-write protection, but "has been written" and "has been accessed" are distinct semantic signals — they happen to share one PTE bit today only because the two implementations share infrastructure. Give RWP its own pagemap category so the UAPI does not conflate them: PAGE_IS_WRITTEN reported on VM_UFFD_WP VMAs, !pte_uffd(pte) PAGE_IS_ACCESSED reported on VM_UFFD_RWP VMAs, !pte_uffd(pte) Both still read the same PTE bit today, but each is scoped to the VMA whose registered mode makes the bit meaningful. If a future implementation moves RWP to a separate PTE bit, only PAGE_IS_ACCESSED switches over. This is a UAPI narrowing. Outside VM_UFFD_WP VMAs the uffd bit is always clear, so PAGEMAP_SCAN used to flag PAGE_IS_WRITTEN on every present PTE there — a meaningless duplicate of PAGE_IS_PRESENT. Now PAGE_IS_WRITTEN fires only inside VM_UFFD_WP VMAs. pagemap_hugetlb_category() now takes the vma like its PTE/PMD peers. Link: https://lore.kernel.org/20260708111417.173443-12-kirill@shutemov.name Signed-off-by: Kiryl Shutsemau <kas@kernel.org> Assisted-by: Claude:claude-opus-4-6 Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Hildenbrand <david@kernel.org> Cc: James Houghton <jthoughton@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: SeongJae Park <sj@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04userfaultfd: add UFFDIO_REGISTER_MODE_RWP and UFFDIO_RWPROTECT plumbingKiryl Shutsemau (Meta)
Add the userspace interface for read-write protection tracking: - UFFDIO_REGISTER_MODE_RWP register a range for RWP tracking - UFFD_FEATURE_RWP capability bit - UFFDIO_RWPROTECT install / remove RWP on a range Introduce CONFIG_USERFAULTFD_RWP, auto-selected on 64-bit kernels with ARCH_HAS_PTE_PROTNONE and HAVE_ARCH_USERFAULTFD_WP. The symbol gates VM_UFFD_RWP (previously aliased to VM_NONE) and the smaps/trace-flag hooks added in the preparatory patches; without it the UAPI bits added here have nothing to drive and would be unreachable. Registration sets VM_UFFD_RWP on the VMA. Combining MODE_WP with MODE_RWP is rejected because both modes claim the uffd PTE bit. UFFDIO_RWPROTECT is the bidirectional counterpart of UFFDIO_WRITEPROTECT: - MODE_RWP change_protection() with MM_CP_UFFD_RWP installs PAGE_NONE and sets the uffd bit on present PTEs - !MODE_RWP change_protection() with MM_CP_UFFD_RWP_RESOLVE restores vma->vm_page_prot and clears the bit userfaultfd_clear_vma() runs the same resolve pass on unregister so RWP state cannot outlive the uffd. Re-registering a range must not drop a mode that installs per-PTE markers (WP or RWP); doing so returns -EBUSY. This also closes a pre-existing window where re-registering without MODE_WP would strand uffd-wp markers: before, those caused extra write-faults but were otherwise benign; with RWP preservation in place, a subsequent mprotect() on a VM_UFFD_RWP VMA would silently promote the stale markers to RWP. The feature is not yet advertised. UFFDIO_REGISTER_MODE_RWP, UFFD_FEATURE_RWP, and _UFFDIO_RWPROTECT are intentionally absent from UFFD_API_REGISTER_MODES, UFFD_API_FEATURES, and UFFD_API_RANGE_IOCTLS, so UFFDIO_API masks them out and the register-mode validator rejects the bit. The follow-up patch adds fault dispatch and exposes the UAPI. Link: https://lore.kernel.org/20260708111417.173443-10-kirill@shutemov.name Signed-off-by: Kiryl Shutsemau <kas@kernel.org> Assisted-by: Claude:claude-opus-4-6 Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Hildenbrand <david@kernel.org> Cc: James Houghton <jthoughton@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: SeongJae Park <sj@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-30mm: move __alloc_pages() to mm/page_alloc.hBrendan Jackman
It's no longer used outside of mm/. Since this means __alloc_pages_noprof() is no longer visible from gfp.h, this also means moving the definition of alloc_pages_node_noprof into the .c file. Also remove references to this API from the documentation tree - referring to the specific function name was already questionable but now the function is not even public it definitely seems wrong. Link: https://lore.kernel.org/20260703-alloc-trylock-v5-14-c87b714e19d3@google.com Signed-off-by: Brendan Jackman <jackmanb@google.com> Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-30Docs/{admin-guide,mm}/damon: fix DAMON documentation detailsDoehyun Baek
Fix minor DAMON documentation issues. Correct the sysfs scheme file name apply_interval_us, the DAMON_STAT module count, a malformed reference, a misplaced label indentation, and a few typos. Link: https://lore.kernel.org/20260629145538.134832-4-sj@kernel.org Signed-off-by: Doehyun Baek <doehyunbaek@gmail.com> Signed-off-by: SJ Park <sj@kernel.org> Reviewed-by: SJ Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> 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> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Asier Gutierrez <gutierrez.asier@huawei-partners.com> Cc: Brendan Higgins <brendan.higgins@linux.dev> Cc: Philippe Laferriere <plafer@proton.me> Cc: Sailesh Nandanavanam <saileshnandanavanam@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-15docs: pagemap: fix flags location, member name and sample codeZenghui Yu
The userland visible page flags (KPF_*) were initially moved to include/linux/kernel-page-flags.h in commit 1a9b5b7fe0c5 ("mm: export stable page flags"), and later moved to include/uapi/linux/kernel-page-flags.h in commit 607ca46e97a1 ("UAPI: (Scripted) Disintegrate include/linux"). Update the doc to reflect the current location of these flags. The member @walk_end of struct pm_scan_arg {} was wrongly written as "end_walk". The first sample code of the PAGEMAP_SCAN ioctl wrongly used the PM_SCAN_CHECK_WPASYNC flag twice, instead of the PM_SCAN_WP_MATCHING flag. The second one included the wrong category in the required mask - PAGE_IS_FILE should be used instead of PAGE_IS_SWAPPED as per the intention. Fix them all together. Signed-off-by: Zenghui Yu <zenghui.yu@linux.dev> Reviewed-by: Lorenzo Stoakes <ljs@kernel.org> Reviewed-by: SeongJae Park <sj@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260626162710.25844-1-zenghui.yu@linux.dev>
2026-06-21selftests/mm: rename hugepage-* tests to hugetlb-*Mike Rapoport (Microsoft)
hugepage could mean both THP and HugeTLB these days. Rename hugepage-* tests for HugeTLB to hugetlb-* to avoid confusion. Make sure that Makefile update keeps alphabetical ordering of the TEST_GEN_FILES entries. Keep old binary names in .gitignore because Linus prefers it this way. Link: https://lore.kernel.org/20260511162840.375890-8-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Donet Tom <donettom@linux.ibm.com> Reviewed-by: Li Wang <li.wang@linux.dev> Tested-by: Sarthak Sharma <sarthak.sharma@arm.com> Tested-by: Luiz Capitulino <luizcap@redhat.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Leon Romanovsky <leon@kernel.org> Cc: Liam Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Nico Pache <npache@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-21selftests/mm: merge map_hugetlb into hugepage-mmapMike Rapoport (Microsoft)
Both tests create a hugettlb mapping, fill it with data and verify the data, the only difference is that one uses file-backed memory and another one uses anonymous memory. Merge both tests into a single file. Link: https://lore.kernel.org/20260511162840.375890-7-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Luiz Capitulino <luizcap@redhat.com> Reviewed-by: Donet Tom <donettom@linux.ibm.com> Tested-by: Luiz Capitulino <luizcap@redhat.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Leon Romanovsky <leon@kernel.org> Cc: Liam Howlett <liam@infradead.org> Cc: Li Wang <li.wang@linux.dev> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Nico Pache <npache@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Sarthak Sharma <sarthak.sharma@arm.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-21Documentation: mm: update the admin guide for mTHP collapseNico Pache
Now that we can collapse to mTHPs lets update the admin guide to reflect these changes and provide proper guidance on how to utilize it. Link: https://lore.kernel.org/20260605161422.213817-15-npache@redhat.com Signed-off-by: Nico Pache <npache@redhat.com> Reviewed-by: Lorenzo Stoakes <ljs@kernel.org> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Lance Yang <lance.yang@linux.dev> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Brendan Jackman <jackmanb@google.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Rientjes <rientjes@google.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Gregory Price <gourry@gourry.net> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Liam R. Howlett <liam@infradead.org> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Rafael Aquini <raquini@redhat.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shivank Garg <shivankg@amd.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Takashi Iwai (SUSE) <tiwai@suse.de> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Usama Arif <usama.arif@linux.dev> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Zach O'Keefe <zokeefe@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-21mm/khugepaged: add per-order mTHP collapse failure statisticsNico Pache
Add three new mTHP statistics to track collapse failures for different orders when encountering swap PTEs, excessive none PTEs, and shared PTEs: - collapse_exceed_swap_pte: Increment when mTHP collapse fails due to encountering a swap PTE. - collapse_exceed_none_pte: Counts when mTHP collapse fails due to exceeding the none PTE threshold for the given order - collapse_exceed_shared_pte: Counts when mTHP collapse fails due to encountering a shared PTE. These statistics complement the existing THP_SCAN_EXCEED_* events by providing per-order granularity for mTHP collapse attempts. The stats are exposed via sysfs under `/sys/kernel/mm/transparent_hugepage/hugepages-*/stats/` for each supported hugepage size. As we currently do not support collapsing mTHPs that contain a swap or shared entry, those statistics keep track of how often we are encountering failed mTHP collapses due to these restrictions. We will add support for mTHP collapse for anonymous pages next; lets also track when this happens at the PMD level within the per-mTHP stats. Link: https://lore.kernel.org/20260605161422.213817-9-npache@redhat.com Signed-off-by: Nico Pache <npache@redhat.com> Reviewed-by: Lorenzo Stoakes <ljs@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Lance Yang <lance.yang@linux.dev> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Brendan Jackman <jackmanb@google.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Rientjes <rientjes@google.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Gregory Price <gourry@gourry.net> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Liam R. Howlett <liam@infradead.org> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Rafael Aquini <raquini@redhat.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shivank Garg <shivankg@amd.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Takashi Iwai (SUSE) <tiwai@suse.de> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Usama Arif <usama.arif@linux.dev> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Zach O'Keefe <zokeefe@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-21mm/khugepaged: generalize alloc_charge_folio()Dev Jain
Pass order to alloc_charge_folio() and update mTHP statistics. Link: https://lore.kernel.org/20260605161422.213817-3-npache@redhat.com Signed-off-by: Dev Jain <dev.jain@arm.com> Co-developed-by: Nico Pache <npache@redhat.com> Signed-off-by: Nico Pache <npache@redhat.com> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Lance Yang <lance.yang@linux.dev> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Lorenzo Stoakes <ljs@kernel.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Acked-by: Usama Arif <usama.arif@linux.dev> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: Barry Song <baohua@kernel.org> Cc: Brendan Jackman <jackmanb@google.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Rientjes <rientjes@google.com> Cc: Gregory Price <gourry@gourry.net> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Liam R. Howlett <liam@infradead.org> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Rafael Aquini <raquini@redhat.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shivank Garg <shivankg@amd.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Takashi Iwai (SUSE) <tiwai@suse.de> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Zach O'Keefe <zokeefe@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-04Docs/admin-guide/mm/damon/usage: clarify current_value of quota goalsMaksym Shcherba
The sysfs interface for DAMON quota goals includes a `current_value` file. This file is not updated by the kernel and only serves to receive user input. Clarify in the documentation that the kernel does not update `current_value`, and that reading it only has meaning when `target_metric` is set to `user_input`. While at it, fix missing commas in the goal files list. Link: https://lore.kernel.org/20260521202020.126500-3-maksym.shcherba@lnu.edu.ua Signed-off-by: Maksym Shcherba <maksym.shcherba@lnu.edu.ua> Reviewed-by: SeongJae Park <sj@kernel.org> Assisted-by: Antigravity:Gemini-3.1-Pro Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-02Docs/{ABI,admin-guide}/damon: fix various typoesZenghui Yu
``damon_target_idx`` was wrongly written as ``target_idx`` in the docs. Fix it all over the place, as well as the wrong directory count, grammar, etc. Link: https://lore.kernel.org/20260520012104.93602-4-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Zenghui Yu <zenghui.yu@linux.dev> Reviewed-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: niecheng <niecheng1@uniontech.com> Cc: Sakurai Shun <ssh1326@icloud.com> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-02Documentation/admin-guide/mm: fix typos in transhuge.rstLeon Hwang
Fix these two typos: 1. approporiately -> appropriately 2. presure -> pressure Link: https://lore.kernel.org/20260520051751.74396-1-leon.hwang@linux.dev Signed-off-by: Leon Hwang <leon.hwang@linux.dev> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Lance Yang <lance.yang@linux.dev> Reviewed-by: SeongJae Park <sj@kernel.org> Reviewed-by: Lorenzo Stoakes <ljs@kernel.org> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Leon Hwang <leon.hwang@linux.dev> Cc: Liam R. Howlett <liam@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Nico Pache <npache@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-02Docs/admin-guide/mm/damon/usage: update for memcg damon filterSeongJae Park
Update DAMON usage document for the newly added belonging memory cgroup attribute monitoring feature. Link: https://lore.kernel.org/20260518234119.97569-29-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-02Docs/admin-guide/mm/damon/usage: document data attributes monitoringSeongJae Park
Update DAMON usage document for the newly added data attributes monitoring feature. Link: https://lore.kernel.org/20260518234119.97569-22-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28Docs/admin-guide/mm/damon/stat: document kdamond_pid parameterSeongJae Park
Update DAMON_STAT usage document for newly added kdamond_pid parameter. Link: https://lore.kernel.org/20260502020505.80822-3-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28Docs/admin-guide/mm/damon/reclaim: update for autotune_monitoring_intervalsSeongJae Park
Update DAMON_RECLAIM usage document for the newly added monitoring intervals auto-tuning enablement parameter. Link: https://lore.kernel.org/20260501011740.81988-3-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28Docs/admin-guide/mm/damon/usage: mark scheme filters sysfs dir as deprecatedSeongJae Park
Patch series "mm/damon/sysfs: document filters/ directory as deprecated". Commit ab71d2d30121 ("mm/damon/sysfs-schemes: let damon_sysfs_scheme_set_filters() be used for different named directories") introduced alternatives of 'filters' directory, namely core_filters/ and 'ops_filters/ directories. Now the alternatives are well stabilized and ready for all users. All filters/ directory use cases are expected to be able to be migrated to the alternatives. An LTS kernel having the alternatives, namely 6.18.y, is also released. Existence of filters/ directory is only confusing. It would be better not immediately removing the directory, though. There could be users that need time before migrating to the alternatives. There might be unexpected use cases that the alternatives cannot support. Doing the deprecation step by step across multiple years like DAMON debugfs deprecation would be safer. Start the deprecation changes by announcing the deprecation on the documents. Every year, one more action for completely removing the directory will be followed, like DAMON debugfs deprecation did. Following yearly actions are currently expected. In 2027, deprecation warning kernel messages will be printed once, for use of filters/ directory. In 2028, filters/ directory will be renamed to filters_DEPRECATED/. In 2029, filters_DEPRECATED/ directory will be removed. This patch (of 2): The alternatives of 'filters/' directory, namely 'core_filters/' and 'ops_filters/', can fully support all the features 'filters/' directory can do, and provide better user experience. Having 'filters/' directory is only confusing to users. Announce it as deprecated on the usage document. Link: https://lore.kernel.org/20260429150309.82282-1-sj@kernel.org Link: https://lore.kernel.org/20260429150309.82282-2-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28Docs/admin-guide/mm/damon/lru_sort: update for entire memory monitoringSeongJae Park
Update DAMON_LRU_SORT usage document for the changed default monitoring target region selection. Link: https://lore.kernel.org/20260429041232.90257-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28Docs/admin-guide/mm/damon/reclaim: update for entire memory monitoringSeongJae Park
Update DAMON_RECLAIM usage document for the changed default monitoring target region selection. Link: https://lore.kernel.org/20260429041232.90257-7-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28Docs/admin-guide/mm/damon/usage: update for pause fileSeongJae Park
Update DAMON usage document for the DAMON context execution pause/resume feature. Link: https://lore.kernel.org/20260427151231.113429-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Brendan Higgins <brendan.higgins@linux.dev> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28Docs/admin-guide/mm/damon: fix 'parametrs' typoCheng-Han Wu
Fix the misspelling of "parametrs" as "parameters" in reclaim.rst and lru_sort.rst. Link: https://lore.kernel.org/20260426231619.107231-3-sj@kernel.org Signed-off-by: Cheng-Han Wu <hank20010209@gmail.com> Signed-off-by: SeongJae Park <sj@kernel.org> Reviewed-by: SeongJae Park <sj@kernel.org> Cc: Asier Gutierrez <gutierrez.asier@huawei-partners.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Liew Rui Yan <aethernet65535@gmail.com> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28Docs/admin-guide/mm/damon/usage: document fail_charge_{num,denom} filesSeongJae Park
Update DAMON usage document for the DAMOS action failed regions quota charge ratio control sysfs files. Link: https://lore.kernel.org/20260428013402.115171-7-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Brendan Higgins <brendan.higgins@linux.dev> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18Docs/admin-guide/mm/damon/lru_sort: warn commit_inputs vs param updates raceSeongJae Park
DAMON_LRU_SORT handles commit_inputs request inside kdamond thread, reading the module parameters. If the user updates the module parameters while the kdamond thread is reading those, races can happen. To avoid this, the commit_inputs parameter shows whether it is still in the progress, assuming users wouldn't update parameters in the middle of the work. Some users might ignore that. Add a warning about the behavior. The issue was discovered in [1] by sashiko. Link: https://lore.kernel.org/20260329153052.46657-3-sj@kernel.org Link: https://lore.kernel.org/20260319161620.189392-2-objecting@objecting.org [1] Fixes: 6acfcd0d7524 ("Docs/admin-guide/damon: add a document for DAMON_LRU_SORT") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: <stable@vger.kernel.org> # 6.0.x Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18Docs/admin-guide/mm/damon/reclaim: warn commit_inputs vs param updates raceSeongJae Park
Patch series "Docs/admin-guide/mm/damon: warn commit_inputs vs other params race". Writing 'Y' to the commit_inputs parameter of DAMON_RECLAIM and DAMON_LRU_SORT, and writing other parameters before the commit_inputs request is completely processed can cause race conditions. While the consequence can be bad, the documentation is not clearly describing that. Add clear warnings. The issue was discovered [1,2] by sashiko. This patch (of 2): DAMON_RECLAIM handles commit_inputs request inside kdamond thread, reading the module parameters. If the user updates the module parameters while the kdamond thread is reading those, races can happen. To avoid this, the commit_inputs parameter shows whether it is still in the progress, assuming users wouldn't update parameters in the middle of the work. Some users might ignore that. Add a warning about the behavior. The issue was discovered in [1] by sashiko. Link: https://lore.kernel.org/20260329153052.46657-2-sj@kernel.org Link: https://lore.kernel.org/20260319161620.189392-3-objecting@objecting.org [1] Link: https://lore.kernel.org/20260319161620.189392-2-objecting@objecting.org [3] Fixes: 81a84182c343 ("Docs/admin-guide/mm/damon/reclaim: document 'commit_inputs' parameter") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: <stable@vger.kernel.org> # 5.19.x Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18kho: document kexec-metadata tracking featureBreno Leitao
Add documentation for the kexec-metadata feature that tracks the previous kernel version and kexec boot count across kexec reboots. This helps diagnose bugs that only reproduce when kexecing from specific kernel versions. Link: https://lore.kernel.org/20260316-kho-v9-6-ed6dcd951988@debian.org Signed-off-by: Breno Leitao <leitao@debian.org> Suggested-by: Mike Rapoport <rppt@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Pratyush Yadav <pratyush@kernel.org> Cc: Alexander Graf <graf@amazon.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: SeongJae Park <sj@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18kho: rename fdt parameter to blob in kho_add/remove_subtree()Breno Leitao
Since kho_add_subtree() now accepts arbitrary data blobs (not just FDTs), rename the parameter from 'fdt' to 'blob' to better reflect its purpose. Apply the same rename to kho_remove_subtree() for consistency. Also rename kho_debugfs_fdt_add() and kho_debugfs_fdt_remove() to kho_debugfs_blob_add() and kho_debugfs_blob_remove() respectively, with the same parameter rename from 'fdt' to 'blob'. Link: https://lore.kernel.org/20260316-kho-v9-2-ed6dcd951988@debian.org Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Pratyush Yadav <pratyush@kernel.org> Cc: Alexander Graf <graf@amazon.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: SeongJae Park <sj@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05Docs/mm/damon: document min_nr_regions constraint and rationaleLiew Rui Yan
The current DAMON implementation requires 'min_nr_regions' to be at least 3. However, this constraint is not explicitly documented in the admin-guide documents, nor is its design rationale explained in the design document. Add a section in design.rst to explain the rationale: the virtual address space monitoring design needs to handle at least three regions to accommodate two large unmapped areas. While this is specific to 'vaddr', DAMON currently enforces it across all operation sets for consistency. Also update reclaim.rst and lru_sort.rst by adding cross-references to this constraint within their respective 'min_nr_regions' parameter description sections, ensuring users are aware of the lower bound. This change is motivated from a recent discussion [1]. Link: https://lkml.kernel.org/r/20260320052428.213230-1-aethernet65535@gmail.com Link: https://lore.kernel.org/damon/20260319151528.86490-1-sj@kernel.org/T/#t [1] Signed-off-by: Liew Rui Yan <aethernet65535@gmail.com> Reviewed-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05Docs/mm/damon: document exclusivity of special-purpose modulesLiew Rui Yan
Add a section in design.rst to explain that DAMON special-purpose kernel modules (LRU_SORT, RECLAIM, STAT) run in an exclusive manner and return -EBUSY if another is already running. Update lru_sort.rst, reclaim.rst and stat.rst by adding cross-references to this exclusivity rule at the end of their respective Example sections. This change is motivated from another discussion [1]. Link: https://lkml.kernel.org/r/20260315162945.80994-1-sj@kernel.org Link: https://lore.kernel.org/damon/20260314002119.79742-1-sj@kernel.org/T/#t [1] Signed-off-by: Liew Rui Yan <aethernet65535@gmail.com> Reviewed-by: SeongJae Park <sj@kernel.org> Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05Docs/admin-guide/mm/damon/usage: document goal_tuner sysfs fileSeongJae Park
Update the DAMON usage document for the new sysfs file for the goal based quota auto-tuning algorithm selection. Link: https://lkml.kernel.org/r/20260310010529.91162-7-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05docs: mm: fix typo in numa_memory_policy.rstAkinobu Mita
Fix a typo: MPOL_INTERLEAVED -> MPOL_INTERLEAVE. Link: https://lkml.kernel.org/r/20260310151837.5888-1-akinobu.mita@gmail.com Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05Docs/admin-guide/mm/damn/lru_sort: fix intervals autotune parameter nameSeongJae Park
The section name should be the same as the parameter name. Fix it. Link: https://lkml.kernel.org/r/20260307195356.203753-6-sj@kernel.org Fixes: ed581147a417 ("Docs/admin-guide/mm/damon/lru_sort: document intervals autotuning") Signed-off-by: SeongJae Park <sj@kernel.org> Acked-by: wang lian <lianux.mm@gmail.com> Cc: Brendan Higgins <brendan.higgins@linux.dev> Cc: David Gow <davidgow@google.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05kho: remove finalize state and clientsJason Miu
Eliminate the `kho_finalize()` function and its associated state from the KHO subsystem. The transition to a radix tree for memory tracking makes the explicit "finalize" state and its serialization step obsolete. Remove the `kho_finalize()` and `kho_finalized()` APIs and their stub implementations. Update KHO client code and the debugfs interface to no longer call or depend on the `kho_finalize()` mechanism. Complete the move towards a stateless KHO, simplifying the overall design by removing unnecessary state management. Link: https://lkml.kernel.org/r/20260206021428.3386442-3-jasonmiu@google.com Signed-off-by: Jason Miu <jasonmiu@google.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Alexander Graf <graf@amazon.com> Cc: Baoquan He <bhe@redhat.com> Cc: Changyuan Lyu <changyuanl@google.com> Cc: David Matlack <dmatlack@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Pratyush Yadav <pratyush@kernel.org> Cc: Ran Xiaokai <ran.xiaokai@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-12Merge tag 'mm-stable-2026-02-11-19-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "powerpc/64s: do not re-activate batched TLB flush" makes arch_{enter|leave}_lazy_mmu_mode() nest properly (Alexander Gordeev) It adds a generic enter/leave layer and switches architectures to use it. Various hacks were removed in the process. - "zram: introduce compressed data writeback" implements data compression for zram writeback (Richard Chang and Sergey Senozhatsky) - "mm: folio_zero_user: clear page ranges" adds clearing of contiguous page ranges for hugepages. Large improvements during demand faulting are demonstrated (David Hildenbrand) - "memcg cleanups" tidies up some memcg code (Chen Ridong) - "mm/damon: introduce {,max_}nr_snapshots and tracepoint for damos stats" improves DAMOS stat's provided information, deterministic control, and readability (SeongJae Park) - "selftests/mm: hugetlb cgroup charging: robustness fixes" fixes a few issues in the hugetlb cgroup charging selftests (Li Wang) - "Fix va_high_addr_switch.sh test failure - again" addresses several issues in the va_high_addr_switch test (Chunyu Hu) - "mm/damon/tests/core-kunit: extend existing test scenarios" improves the KUnit test coverage for DAMON (Shu Anzai) - "mm/khugepaged: fix dirty page handling for MADV_COLLAPSE" fixes a glitch in khugepaged which was causing madvise(MADV_COLLAPSE) to transiently return -EAGAIN (Shivank Garg) - "arch, mm: consolidate hugetlb early reservation" reworks and consolidates a pile of straggly code related to reservation of hugetlb memory from bootmem and creation of CMA areas for hugetlb (Mike Rapoport) - "mm: clean up anon_vma implementation" cleans up the anon_vma implementation in various ways (Lorenzo Stoakes) - "tweaks for __alloc_pages_slowpath()" does a little streamlining of the page allocator's slowpath code (Vlastimil Babka) - "memcg: separate private and public ID namespaces" cleans up the memcg ID code and prevents the internal-only private IDs from being exposed to userspace (Shakeel Butt) - "mm: hugetlb: allocate frozen gigantic folio" cleans up the allocation of frozen folios and avoids some atomic refcount operations (Kefeng Wang) - "mm/damon: advance DAMOS-based LRU sorting" improves DAMOS's movement of memory betewwn the active and inactive LRUs and adds auto-tuning of the ratio-based quotas and of monitoring intervals (SeongJae Park) - "Support page table check on PowerPC" makes CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc (Andrew Donnellan) - "nodemask: align nodes_and{,not} with underlying bitmap ops" makes nodes_and() and nodes_andnot() propagate the return values from the underlying bit operations, enabling some cleanup in calling code (Yury Norov) - "mm/damon: hide kdamond and kdamond_lock from API callers" cleans up some DAMON internal interfaces (SeongJae Park) - "mm/khugepaged: cleanups and scan limit fix" does some cleanup work in khupaged and fixes a scan limit accounting issue (Shivank Garg) - "mm: balloon infrastructure cleanups" goes to town on the balloon infrastructure and its page migration function. Mainly cleanups, also some locking simplification (David Hildenbrand) - "mm/vmscan: add tracepoint and reason for kswapd_failures reset" adds additional tracepoints to the page reclaim code (Jiayuan Chen) - "Replace wq users and add WQ_PERCPU to alloc_workqueue() users" is part of Marco's kernel-wide migration from the legacy workqueue APIs over to the preferred unbound workqueues (Marco Crivellari) - "Various mm kselftests improvements/fixes" provides various unrelated improvements/fixes for the mm kselftests (Kevin Brodsky) - "mm: accelerate gigantic folio allocation" greatly speeds up gigantic folio allocation, mainly by avoiding unnecessary work in pfn_range_valid_contig() (Kefeng Wang) - "selftests/damon: improve leak detection and wss estimation reliability" improves the reliability of two of the DAMON selftests (SeongJae Park) - "mm/damon: cleanup kdamond, damon_call(), damos filter and DAMON_MIN_REGION" does some cleanup work in the core DAMON code (SeongJae Park) - "Docs/mm/damon: update intro, modules, maintainer profile, and misc" performs maintenance work on the DAMON documentation (SeongJae Park) - "mm: add and use vma_assert_stabilised() helper" refactors and cleans up the core VMA code. The main aim here is to be able to use the mmap write lock's lockdep state to perform various assertions regarding the locking which the VMA code requires (Lorenzo Stoakes) - "mm, swap: swap table phase II: unify swapin use" removes some old swap code (swap cache bypassing and swap synchronization) which wasn't working very well. Various other cleanups and simplifications were made. The end result is a 20% speedup in one benchmark (Kairui Song) - "enable PT_RECLAIM on more 64-bit architectures" makes PT_RECLAIM available on 64-bit alpha, loongarch, mips, parisc, and um. Various cleanups were performed along the way (Qi Zheng) * tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (325 commits) mm/memory: handle non-split locks correctly in zap_empty_pte_table() mm: move pte table reclaim code to memory.c mm: make PT_RECLAIM depends on MMU_GATHER_RCU_TABLE_FREE mm: convert __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config um: mm: enable MMU_GATHER_RCU_TABLE_FREE parisc: mm: enable MMU_GATHER_RCU_TABLE_FREE mips: mm: enable MMU_GATHER_RCU_TABLE_FREE LoongArch: mm: enable MMU_GATHER_RCU_TABLE_FREE alpha: mm: enable MMU_GATHER_RCU_TABLE_FREE mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h mm/damon/stat: remove __read_mostly from memory_idle_ms_percentiles zsmalloc: make common caches global mm: add SPDX id lines to some mm source files mm/zswap: use %pe to print error pointers mm/vmscan: use %pe to print error pointers mm/readahead: fix typo in comment mm: khugepaged: fix NR_FILE_PAGES and NR_SHMEM in collapse_file() mm: refactor vma_map_pages to use vm_insert_pages mm/damon: unify address range representation with damon_addr_range mm/cma: replace snprintf with strscpy in cma_new_area ...
2026-02-02docs: fix 're-use' -> 'reuse' in documentationRhys Tumelty
Signed-off-by: Rhys Tumelty <rhys@tumelty.co.uk> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260128220233.179439-1-rhys@tumelty.co.uk>
2026-01-31Docs/admin-guide/mm/damon/usage: update stats update process for refresh_msSeongJae Park
DAMOS stats on sysfs was only manually updated. Recent addition of 'refresh_ms' knob enabled periodic and automated updates of the stats. The document for stats update process is not updated for the change, however. Update. Link: https://lkml.kernel.org/r/20260118180305.70023-7-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-31Docs/admin-guide/mm/damon/usage: introduce DAMON modules at the beginningSeongJae Park
DAMON usage document provides a list of available DAMON interfaces with brief introduction at the beginning of the doc. The list is missing DAMON modules for special purposes, while it is one of the major suggested interfaces. Add an item for those to the list. Link: https://lkml.kernel.org/r/20260118180305.70023-6-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-31mm: rename CONFIG_BALLOON_COMPACTION to CONFIG_BALLOON_MIGRATIONDavid Hildenbrand (Red Hat)
While compaction depends on migration, the other direction is not the case. So let's make it clearer that this is all about migration of balloon pages. Adjust all comments/docs in the core to talk about "migration" instead of "compaction". While at it add some "/* CONFIG_BALLOON_MIGRATION */". Link: https://lkml.kernel.org/r/20260119230133.3551867-23-david@kernel.org Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Eugenio Pérez <eperezma@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jason Wang <jasowang@redhat.com> Cc: Jerrin Shaji George <jerrin.shaji-george@broadcom.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: SeongJae Park <sj@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26Docs/admin-guide/mm/damon/lru_sort: document intervals autotuningSeongJae Park
Document a newly added DAMON_LRU_SORT module parameter for using monitoring intervals auto-tuning feature of DAMON. Link: https://lkml.kernel.org/r/20260113152717.70459-12-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Acked-by: wang lian <lianux.mm@gmail.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26Docs/admin-guide/mm/damon/lru_sort: document active_mem_bp parameterSeongJae Park
Document a newly added DAMON_LRU_SORT parameter for doing auto-tuning aiming an active to inactive memory size ratio. Link: https://lkml.kernel.org/r/20260113152717.70459-10-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Acked-by: wang lian <lianux.mm@gmail.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26Docs/admin-guide/mm/damon/lru_sort: document filter_young_pagesSeongJae Park
Document the new DAMON_LRU_SORT parameter, filter_young_pages. It can be used to use page level access re-check for the LRU sorting. Link: https://lkml.kernel.org/r/20260113152717.70459-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Acked-by: wang lian <lianux.mm@gmail.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20mm, hugetlb: implement movable_gigantic_pages sysctlGregory Price
This reintroduces a concept removed by: commit d6cb41cc44c6 ("mm, hugetlb: remove hugepages_treat_as_movable sysctl") This sysctl provides flexibility between ZONE_MOVABLE use cases: 1) onlining memory in ZONE_MOVABLE to maintain hotplug compatibility 2) onlining memory in ZONE_MOVABLE to make hugepage allocate reliable When ZONE_MOVABLE is used to make huge page allocation more reliable, disallowing gigantic pages memory in this region is pointless. If hotplug is not a requirement, we can loosen the restrictions to allow 1GB gigantic pages in ZONE_MOVABLE. Since 1GB can be difficult to migrate / has impacts on compaction / defragmentation, we don't enable this by default. Notably, 1GB pages can only be migrated if another 1GB page is available - so hot-unplug will fail if such a page cannot be found. However, since there are scenarios where gigantic pages are migratable, we should allow use of these on movable regions. When not valid 1GB is available for migration, hot-unplug will retry indefinitely (or until interrupted). For example: echo 0 > node0/hugepages/..-1GB/nr_hugepages # clear node0 1GB pages echo 1 > node1/hugepages/..-1GB/nr_hugepages # reserve node1 1GB page ./alloc_huge_node1 & # Allocate a 1GB page on node1 ./node1_offline & # attempt to offline all node1 memory echo 1 > node0/hugepages/..-1GB/nr_hugepages # reserve node0 1GB page In this example, node1_offline will block indefinitely until the final step, when a node0 1GB page is made available. Note: Boot-time CMA is not possible for driver-managed hotplug memory, as CMA requires the memory to be registered as SystemRAM at boot time. Additionally, 1GB huge pages are not supported by THP. Link: https://lkml.kernel.org/r/20251221125603.2364174-1-gourry@gourry.net Signed-off-by: Gregory Price <gourry@gourry.net> Suggested-by: David Rientjes <rientjes@google.com> Link: https://lore.kernel.org/all/20180201193132.Hk7vI_xaU%25akpm@linux-foundation.org/ Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: "David Hildenbrand (Red Hat)" <david@kernel.org> Cc: Gregory Price <gourry@gourry.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20Docs/admin-guide/mm/damon/usage: update for max_nr_snapshotsSeongJae Park
Update DAMON usage document for the newly added DAMON sysfs interface file, max_nr_snapshots. Link: https://lkml.kernel.org/r/20251216080128.42991-11-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20Docs/admin-guide/mm/damon/usage: update for nr_snapshots damos statSeongJae Park
Update DAMON usage document for the newly added damos stat, nr_snapshots. Link: https://lkml.kernel.org/r/20251216080128.42991-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-24pagemap: update BUDDY flag documentationRichard Weinberger
Since v4.6 the BUDDY flag is set for _all_ pages in the block and no longer just for the first one. This change was introduced by: commit 832fc1de01ae ("/proc/kpageflags: return KPF_BUDDY for "tail" buddy pages") Strictly speaking, this was an ABI change, but as nobody has noticed since 2016, let's just update the documentation. Link: https://lkml.kernel.org/r/20251122211920.3410371-1-richard@nod.at Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Vladimir Davydov <vdavydov@virtuozzo.com>> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>