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10 daysMerge 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 ...
2026-08-06dax/kmem: add sysfs interface for atomic whole-device hotplugGregory Price
There is no atomic mechanism to offline and remove an entire multi-block DAX kmem device. This is presently done in two steps: 1. offline all 2. remove all This creates a race condition where another entity operates directly on the memory blocks and can cause hot-unplug to fail / unbind to deadlock. Add a new 'state' sysfs attribute that enables an atomic whole-device hotplug operation across its entire memory region. daxX.Y/state mirrors the per-block memoryX/state ABI: - [offline, online, online_kernel, online_movable] - "unplugged" - is added specifically for dax0.0/state The valid writable states include: - "unplugged": memory blocks are not present - "online": memory is online, zone chosen by the kernel - "online_kernel": memory is online in ZONE_NORMAL - "online_movable": memory is online in ZONE_MOVABLE Valid transitions: - unplugged -> online[_kernel|_movable] - online[_kernel|_movable] -> unplugged - offline -> unplugged A device can only be onlined from "unplugged", so it must be returned there before being onlined into a different state. For backwards compatibility the memory blocks are always created at probe - existing tools expect them to be present after kmem binds. "offline" is therefore a reportable state but is not writable: it only arises from the legacy auto_online_blocks=offline policy. Onlining such a device through this attribute requires unplugging it first in an effort to get drivers creating DAX devices to set a default. Unplug is atomic across the whole device: dax_kmem_do_hotremove() collects every added range and offlines/removes them in one operation. Either the operation succeeds or is entirely rolled back. Unbind Note: An offline dax device memory is removed on unbind as before. If online at unbind, the resources are leaked (as before), but now we prevent deadlock if a memory region is impossible to hotremove. Link: https://lore.kernel.org/20260712154505.3564379-10-gourry@gourry.net Signed-off-by: Gregory Price <gourry@gourry.net> Suggested-by: Hannes Reinecke <hare@suse.de> Suggested-by: David Hildenbrand <david@kernel.org> Reviewed-by: Dan Williams <djbw@kernel.org> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Danilo Krummrich <dakr@kernel.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 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: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Gupta <pankaj.gupta@amd.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06dax/kmem: extract hotplug/hotremove helper functionsGregory Price
Refactor kmem _probe() _remove() by extracting init, cleanup, hotplug, and hot-remove logic into separate helper functions: - dax_kmem_init_resources: inits IO_RESOURCE w/ request_mem_region - dax_kmem_cleanup_resources: cleans up initialized IO_RESOURCE - dax_kmem_do_hotplug: handles memory region reservation and adding - dax_kmem_do_hotremove: handles memory removal and resource cleanup This is a pure refactoring with no functional change. The helpers will enable future extensions to support more granular control over memory hotplug operations. We need to split hotplug/hotunplug and init/cleanup in order to have the resources available for hot-add. Otherwise, when probe occurs, the dax devices are never added to sysfs because the resources are never registered. Detaching hotunplug/cleanup allows us to re-use the hotunplug code without destroying the underlying resources. Link: https://lore.kernel.org/20260712154505.3564379-9-gourry@gourry.net Signed-off-by: Gregory Price <gourry@gourry.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Danilo Krummrich <dakr@kernel.org> Cc: David Hildenbrand (Arm) <david@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hannes Reinecke <hare@suse.de> 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: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Gupta <pankaj.gupta@amd.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06dax/kmem: resolve default online type at probe timeGregory Price
Resolve the default online type in kmem at probe time explicitly instead of implicitly inheriting the system default by calling add_memory_driver_managed(). No behavioral change at this point (still system default). Link: https://lore.kernel.org/20260712154505.3564379-8-gourry@gourry.net Signed-off-by: Gregory Price <gourry@gourry.net> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Danilo Krummrich <dakr@kernel.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: David Hildenbrand (Arm) <david@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hannes Reinecke <hare@suse.de> 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: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Gupta <pankaj.gupta@amd.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06mm/memory: add memory_block_aligned_range() helperGregory Price
Patch series "dax/kmem: atomic whole-device hotplug via sysfs", v7. The dax kmem driver onlines memory during probe using the system default policy, with no atomic control for the state of an entire region at runtime - only by toggling individual memory blocks. Offlining and removing a whole region therefore races with other userland controllers that interfere between the two steps. This series adds a sysfs "state" attribute for atomic whole-device hotplug control, plus the mm and dax plumbing to support it. Transitions are atomic across every range of the device. The state names mirror the per-block memoryX/state ABI with one modification: - "unplugged": memory blocks are not present - "online": online as system RAM, zone chosen by the kernel - "online_kernel": online in ZONE_NORMAL - "online_movable": online in ZONE_MOVABLE "offline" (blocks present but offline) is reportable for backward compatibility but is not writable because it entices the race condition we are trying to solve (separate atomic steps for offline and unplug). 'unplugged' (atomic offline+remove of the whole device) is the new capability provided by the new kmem sysfs attribute. dax/kmem probe still creates the memory blocks by default when the default policy is "offline", to preserve backwards compatibility. This patch (of 10): Memory hotplug operations require ranges aligned to memory block boundaries. This is a generic operation for hotplug. Add memory_block_aligned_range() as a common helper in <linux/memory.h> that aligns the start address up and end address down to memory block boundaries. Guard against end underflow when the range falls below the first memory block boundary, returning an empty range instead. Update dax/kmem to use this helper. Link: https://lore.kernel.org/20260712154505.3564379-1-gourry@gourry.net Link: https://lore.kernel.org/20260712154505.3564379-2-gourry@gourry.net Signed-off-by: Gregory Price <gourry@gourry.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Dan Williams <djbw@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Danilo Krummrich <dakr@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 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: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Hannes Reinecke <hare@suse.de> Cc: Pankaj Gupta <pankaj.gupta@amd.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-14dax: fsdev.c minor formatting cleanupJohn Groves
Address some comments from Jonathan that were missed in the merged series. Fix line wrapping in fsdev_dax_recovery_write() and fsdev_dax_zero_page_range() signatures. Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019ecc09f607-b558c192-72fc-4c2d-9f64-3b82796e7dd4-000000@email.amazonses.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-07-14dax: fix holder_ops race in fs_put_dax()John Groves
Clear holder_ops before holder_data so that a concurrent fs_dax_get() cannot have its newly installed holder_ops overwritten. cmpxchg() provides release ordering on weakly-ordered architectures, ensuring the WRITE_ONCE(holder_ops, NULL) store is visible to any CPU that observes the holder_data release. Add a WARN_ON() that fires only when the cmpxchg observes a non-NULL value that is not @holder, i.e. fs_put_dax() called by something that is not the current holder. That is an API contract violation; the WARN_ON() does not prevent the damage but makes the bug visible. A NULL cmpxchg result is deliberately tolerated: kill_dax() clears holder_data while a holder is still attached when a device is removed out from under a mounted filesystem (after delivering MF_MEM_PRE_REMOVE). The holder's subsequent fs_put_dax() - e.g. xfs_free_buftarg() after a forced shutdown - then legitimately finds holder_data already NULL, so warning on that case would turn supported device removal into a splat (or a panic with panic_on_warn). Also add a kerneldoc comment documenting that fs_put_dax() must only be called by the current holder. Fixes: eec38f5d86d27 ("dax: Add fs_dax_get() func to prepare dax for fs-dax usage") Signed-off-by: John Groves <john@groves.net> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/0100019ecc09dcab-2f4aa175-0b84-4b36-9e54-ebff302ebb0a-000000@email.amazonses.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-07-14dax: read holder_ops once in dax_holder_notify_failure()John Groves
dax_holder_notify_failure() reads dax_dev->holder_ops twice without READ_ONCE() -- once for the NULL check and once for the indirect notify_failure() call. A concurrent fs_put_dax() can clear holder_ops between the two reads, so the check can observe a non-NULL pointer while the call dereferences NULL. (kill_dax() also clears holder_ops, but only after synchronize_srcu(), so it cannot race a reader that is inside dax_read_lock(); fs_put_dax() does no such synchronization.) Fetch holder_ops once into a local with READ_ONCE() so the NULL check and the indirect call observe the same value. Fixes: 8012b86608552 ("dax: introduce holder for dax_device") Suggested-by: Richard Cheng <icheng@nvidia.com> Reviewed-by: Richard Cheng <icheng@nvidia.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019ecc09bb56-5ecc9c6b-35ba-44f8-b112-921b01b34478-000000@email.amazonses.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-07-14dax/fsdev: fail probe on invalid pgmap offsetJohn Groves
Convert the WARN_ON to a fatal error when pgmap_phys > phys. This condition means the remapped region starts after the device's data region, which is an impossible state. Previously the probe continued with data_offset=0, leaving virt_addr silently misaligned. Now probe returns -EINVAL with a diagnostic message. Fixes: 759455848df0b ("dax: Save the kva from memremap") Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019ecc0999fa-97574544-8b6b-46cf-9f33-423abdbeee7f-000000@email.amazonses.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-07-14dax/fsdev: use __va(phys) for kaddr in direct_accessJohn Groves
Use __va(phys) instead of virt_addr + linear_offset for the kaddr return in __fsdev_dax_direct_access(). The previous code added a device-linear byte offset to virt_addr (which is __va of ranges[0]), but for multi-range devices with physical gaps between ranges, this linear arithmetic crosses the gap and produces a wrong kernel virtual address. Using __va(phys) where phys comes from dax_pgoff_to_phys() is correct for any range layout because the direct map translates each physical address independently. This leaves dev_dax->virt_addr write-only, so remove the field (suggested by Dave Jiang). Fixes: 759455848df0b ("dax: Save the kva from memremap") Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019ecc096de8-8bc254a7-d2cc-44b6-82b1-1394fda8bb41-000000@email.amazonses.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-07-14dax/fsdev: clear pgmap ops and owner on unbindJohn Groves
fsdev_dax_probe() sets pgmap->ops = &fsdev_pagemap_ops and pgmap->owner = dev_dax, but nothing ever clears them. For a dynamic device the pgmap is devm-allocated and freed on unbind, so this is harmless. For a static device the pgmap is the shared, long-lived one owned by the dax bus (kill_dev_dax() only NULLs dev_dax->pgmap for the non-static case), and device.c's probe sets only pgmap->type, never clearing ops/owner. So after fsdev unbinds a static device the stale fsdev_pagemap_ops survives on the shared pgmap. If the device is then rebound to device_dax (MEMORY_DEVICE_GENERIC, which installs no ->memory_failure), or the fsdev_dax module is unloaded, a subsequent memory_failure on that pgmap dispatches through the stale -- and possibly freed -- handler. Register a devm action that clears pgmap->ops and pgmap->owner on unbind, symmetric with setting them at probe, so the pgmap carries no fsdev state once fsdev is detached. Suggested-by: Richard Cheng <icheng@nvidia.com> Fixes: d5406bd458b0a ("dax: add fsdev.c driver for fs-dax on character dax") Signed-off-by: John Groves <john@groves.net> Reviewed-by: Richard Cheng <icheng@nvidia.com> Link: https://patch.msgid.link/0100019ecc094b6e-fc163bde-0396-4a33-909f-fb88e740be27-000000@email.amazonses.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-07-14dax/fsdev: don't leave a dangling dev_dax->pgmap on probe failureJohn Groves
After the dynamic path set dev_dax->pgmap, any later probe failure left dev_dax->pgmap dangling: devres frees the devm_kzalloc'd pgmap on probe failure, and subsequent probe attempts would hit the "dynamic-dax with pre-populated page map" check and fail permanently. Factor pgmap acquisition out into fsdev_acquire_pgmap(), and defer the dev_dax->pgmap assignment until probe can no longer fail. A failed probe now never publishes the pointer at all, so there is nothing to unwind. This also matches kill_dev_dax(), which already clears the dynamic pgmap pointer on unbind: dev_dax->pgmap is now non-NULL only while the pgmap is actually valid. Refactor suggested by Dave Jiang. Fixes: d5406bd458b0a ("dax: add fsdev.c driver for fs-dax on character dax") Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019ecc092ca1-ffc7a5fd-1252-4be5-882c-fd5efdc102a9-000000@email.amazonses.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-07-14dax/fsdev: clear vmemmap_shift when binding static pgmapJohn Groves
Clear pgmap->vmemmap_shift for static DAX devices. When rebinding a static device from device_dax (which may set vmemmap_shift based on alignment) to fsdev_dax, the stale vmemmap_shift persists on the shared pgmap. Explicitly zero it before devm_memremap_pages() so the vmemmap is built for order-0 folios as fsdev requires. Fixes: d5406bd458b0a ("dax: add fsdev.c driver for fs-dax on character dax") Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019ecc090eea-7c46f51e-5393-402c-850d-78059bb6d343-000000@email.amazonses.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-07-14dax/fsdev: fix multi-range offset in memory_failure handlerJohn Groves
Fix memory_failure offset calculation for multi-range devices. The old code subtracted ranges[0].range.start from the faulting PFN's physical address, which produces an incorrect (inflated) logical offset when the PFN falls in ranges[1] or beyond due to physical gaps between ranges. Add fsdev_pfn_to_offset() to walk the range list and compute the correct device-linear byte offset relative to ranges[0].start (the device data start) -- the base the holder (xfs, famfs) maps from -- for both static and dynamic devices. V5 walked the pagemap's immutable pgmap->ranges[] instead, to avoid reading the mutable dev_dax->ranges[] from this callback. That had a different problem: it regressed static devices, where pgmap->ranges[0].start can sit data_offset below the data start, so the reported offset came out data_offset too high and the holder would act on the wrong blocks. For dynamic devices the two arrays are identical, so pgmap->ranges[] only ever helped the dynamic case while breaking the static one. Walk dev_dax->ranges[] instead. (Richard Cheng spotted the static regression.) Reading dev_dax->ranges[] here may race a concurrent krealloc() of the range array via sysfs (mapping_store(), under dax_region_rwsem, which this ->memory_failure callback does not hold). That exposure is pre-existing -- the original single-range code read dev_dax->ranges[0] locklessly as well -- so this patch does not make it worse; a proper fix (locking or snapshotting) belongs in a separate change. Fixes: d5406bd458b0a ("dax: add fsdev.c driver for fs-dax on character dax") Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Signed-off-by: John Groves <john@groves.net> Reviewed-by: Richard Cheng <icheng@nvidia.com> Link: https://patch.msgid.link/0100019ecc08d74f-ec0d09b8-11e9-4e5b-af48-8c6d382af486-000000@email.amazonses.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-06-19Merge tag 'mm-stable-2026-06-18-09-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "selftests/mm: clean up build output and verbosity" (Li Wang) Remove some noise from the MM selftests build - "mm: Free contiguous order-0 pages efficiently" (Ryan Roberts) Speed up the freeing of a batch of 0-order pages by first scanning them for coalescing opportunities. This is applicable to vfree() and to the releasing of frozen pages - "mm/damon: introduce DAMOS failed region quota charge ratio" (SeongJae Park) Address a DAMOS usability issue: The DAMOS quota often exhausts prematurely because it charges for all memory attempted, causing slow and inconsistent performance when actions fail on unreclaimable memory. To fix this, a new feature lets users set a smaller, flexible quota charge ratio (via a numerator and denominator) for failed regions. Since failed actions cause less overhead, reducing their quota cost ensures more predictable and efficient DAMOS processing - "selftests/cgroup: improve zswap tests robustness and support large page sizes" (Li Wang) Fix various spurious failures and improves the overall robustness of the cgroup zswap selftests - "fix MAP_DROPPABLE not supported errno" (Anthony Yznaga) Fix an issue in the mlock selftests on arm32 - "mm: huge_memory: clean up defrag sysfs with shared" (Breno Leitao) Some maintenance work in the huge_memory code - "treewide: fixup gfp_t printks" (Brendan Jackman) Use the special vprintf() gfp_t conversion in various places - "mm: Fix vmemmap optimization accounting and initialization" (Muchun Song) Fix several bugs in the vmemmap optimization, mainly around incorrect page accounting and memmap initialization in the DAX and memory hotplug paths. It also fixes pageblock migratetype initialization and struct page initialization for ZONE_DEVICE compound pages - "mm/damon: repost non-hotfix reviewed patches in damon/next tree" A sprinkle of unrelated minor bugfixes for DAMON - "mm: remove page_mapped()" (David Hildenbrand) Remove this function from the tree, replacing it with folio_mapped() - "mm/damon: let DAMON be paused and resumed" (SeongJae Park) Allow DAMON to be paused and resumed without losing its current state - "kasan: hw_tags: Disable tagging for stack and page-tables" (Muhammad Usama Anjum) Simplify and speed up kasan by removing its ineffective tagging of stacks and page tables - "mm/damon/reclaim,lru_sort: monitor all system rams by default" (SeongJae Park) Simplify deployment on diverse hardware like NUMA systems by updating DAMON_RECLAIM and DAMON_LRU_SORT to automatically monitor the physical address range covering all System RAM areas by default, replacing the overly restrictive behavior that only targeted the single largest memory block to save on negligible overhead - "mm/damon/sysfs: document filters/ directory as deprecated" (SeongJae Park) Update some DAMON docs - "mm: use spinlock guards for zone lock" (Dmitry Ilvokhin) Switch zone->lock handling over to using the guard() mechanisms - "mm/filemap: tighten mmap_miss hit accounting" (fujunjie) Fix a flaw where the mmap_miss counter over-credited page cache hits during fault-arounds and page-fault retries. This results in significant reduction of redundant synchronous mmap readahead I/O, drastically cutting down execution time and gigabytes read for sparse random or strided memory access workloads - "selftests/cgroup: Fix false positive failures in test_percpu_basic" (Li Wang) Fix a couple of false-positives in the cgroup kmem selftests - "mm/damon/reclaim: support monitoring intervals auto-tuning" (SeongJae Park) Add a new parameter to DAMON permitting DAMON_RECLAIM to automatically tune DAMON's sampling and aggregation intervals - "mm/damon/stat: add kdamond_pid parameter" (SeongJae Park) Change DAMON_STAT to provide the pid of its kdamond - "mm/kmemleak: dedupe verbose scan output" (Breno Leitao) Remove large amounts of duplicated backtraces from the verbose-mode kmemleak output - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 1)" (David Hildenbrand) Reduce our use of CONFIG_HAVE_BOOTMEM_INFO_NODE, with a view to removing it entirely in a later series - "mm/damon: validate min_region_size to be power of 2" (Liew Rui Yan) Prevent users from passing a non-power-of-2 value of `addr_unit', as this later results in undesirable behavior - "mm: document read_pages and simplify usage" (Frederick Mayle) - "tools/mm/page-types: Fix misc bugs" (Ye Liu) Fix three issues in tools/mm/page-types.c - "mm: misc cleanups from __GFP_UNMAPPED series" (Brendan Jackman) Implement several cleanups in the page allocator and related code - "mm, swap: swap table phase IV: unify allocation" (Kairui Song) Unify the allocation and charging of anon and shmem swap in folios, provides better synchronization, consolidates the metadata management, hence dropping the static array and map, and improves performance - "mm/damon: introduce data attributes monitoring" (SeongJae Park( Extend DAMON to monitor general data attributes other than accesses - "mm/vmalloc: free unused pages on vrealloc() shrink" (Shivam Kalra) Implement the TODO in vrealloc() to unmap and free unused pages when shrinking across a page boundary - "mm/damon: documentation and comment fixes" (niecheng) - "remove mmap_action success, error hooks" (Lorenzo Stoakes) Eliminate custom hooks from mmap_action by removing the problematic success_hook which allowed drivers to improperly access uninitialized VMAs. It replaces the error_hook with a simple error-code field and updates the memory char driver accordingly - "mm/damon: minor improvements for code readability and tests" (SeongJae Park) - "mm/damon: fix macro arguments and clarify quota goals doc" (Maksym Shcherba) - "userfaultfd: merge fs/userfaultfd.c into mm/userfaultfd.c" (Mike Rapoport) - "mm/mglru: improve reclaim loop and dirty folio" (Kairui Song and others) Clean up and slightly improves MGLRU's reclaim loop and dirty writeback handling. Large performance improvements are measured - "use vma locks for proc/pid/{smaps|numa_maps} reads" (Suren Baghdasaryan) Use per-vma locks when reading /proc/pid/smaps and numa_maps similar to reduce contention on central mmap_lock - "refactors thpsize_shmem_enabled_store() and thpsize_shmem_enabled_show()" (Ran Xiaokai) Some cleanup work in the THP code - "selftests/memfd: fix compilation warnings" (Konstantin Khorenko) Fix a few build glitches in the memfd selftest code. - "memcg: shrink obj_stock_pcp and cache multiple objcgs" (Shakeel Butt) Resolve a 68% performance regression caused by NUMA-node cache thrashing around struct obj_stock_pcp by shrinking its existing fields and expanding it into a multi-slot array that caches up to five obj_cgroup pointers per CPU, allowing per-node variants of the same memcg to coexist within a single 64-byte cache line. - "zram: writeback fixes" (Sergey Senozhatsky) address a couple of unrelated zram writeback issues - "mm: switch THP shrinker to list_lru" (Johannes Weiner) Resolve NUMA-awareness issues and streamlines callsite interaction by refactoring and extending the list_lru API to completely replace the complex, open-coded deferred split queue for Transparent Huge Pages - "mm: improve large folio readahead for exec memory" (Usama Arif) Improve large-folio readahead on systems like 64K-page arm64 by preventing the mmap_miss check from permanently disabling target-oriented VM_EXEC readahead, and by generalizing the force_thp_readahead gate to support mappings with any usefully large maximum folio order under the cache cap. - "userfaultfd/pagemap: pre-existing fixes" (Kiryl Shutsemau) Fix a bunch of minor issues in the userfaultfd/pagemap, all of which were flagged by Sashiko review of proposed new material - "mm/sparse-vmemmap: Provide generic vmemmap_set_pmd() and vmemmap_check_pmd()" (Muchun Song) Provide generic versions of these two functions so the four arch-specific implementations can be removed. - "mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device" (Youngjun Park) Address a uswsusp-vs-swapoff race and reduces the swap device reference taking/releasing frequency. - "mm/hmm: A fix and a selftest" (Dev Jain) * tag 'mm-stable-2026-06-18-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) selftests/mm/hmm-tests: test pagemap reads of PMD device-private entries fs/proc/task_mmu: do not warn on seeing non-migration pmd entry lib/test_hmm: check alloc_page_vma() return value and handle OOM mm/compaction: cap compact_gap() at COMPACT_CLUSTER_MAX mm/swap: remove redundant swap device reference in alloc/free mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device mm/filemap: use folio_next_index() for start vmalloc: fix NULL pointer dereference in is_vm_area_hugepages() sparc/mm: drop vmemmap_check_pmd helper and use generic code loongarch/mm: drop vmemmap_check_pmd helper and use generic code riscv/mm: drop vmemmap_pmd helpers and use generic code arm64/mm: drop vmemmap_pmd helpers and use generic code mm/sparse-vmemmap: provide generic vmemmap_set_pmd() and vmemmap_check_pmd() rust: page: mark Page::nid as inline userfaultfd: build __VMA_UFFD_FLAGS from config-gated masks userfaultfd: gate must_wait writability check on pte_present() mm/huge_memory: preserve pmd_swp_uffd_wp on device-private PMD downgrade fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole() fs/proc/task_mmu: use huge_page_size() in pagemap_scan_hugetlb_entry() fs/proc/task_mmu: fix make_uffd_wp_huge_pte() prot-update race ...
2026-06-01dax/bus: Upgrade resource conflict message to dev_err() in alloc_dax_region()Tomasz Wolski
The dax_region resource conflict in alloc_dax_region() indicates a serious configuration problem — two subsystems (e.g. dax_hmem and dax_cxl) are attempting to register overlapping address ranges. This is not a transient or debug-level condition; it represents a genuine resource conflict that an administrator needs to be aware of. Promote the log level from dev_dbg() to dev_err() so that the conflict is visible by default without requiring dynamic debug to be enabled. Suggested-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/linux-cxl/69c1a8d1c0fa9_7ee3100a1@dwillia2-mobl4.notmuch/ Signed-off-by: Tomasz Wolski <tomasz.wolski@fujitsu.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Richard Cheng <icheng@nvidia.com> Link: https://patch.msgid.link/20260528064546.23362-1-tomasz.wolski@fujitsu.com Signed-off-by: Alison Schofield <alison.schofield@intel.com>
2026-05-28dax/kmem: account for partial discontiguous resource upon removalDavidlohr Bueso
When dev_dax_kmem_probe() partially succeeds (at least one range is mapped) but a subsequent range fails request_mem_region() or add_memory_driver_managed(), the probe silently continues, ultimately returning success, but with the corresponding range resource NULL'ed out. dev_dax_kmem_remove() iterates over all dax_device ranges regardless of if the underlying resource exists. When remove_memory() is called later, it returns 0 because the memory was never added which causes dev_dax_kmem_remove() to incorrectly assume the (nonexistent) resource can be removed and attempts cleanup on a NULL pointer. Fix this by skipping these ranges altogether, noting that these cases are considered success, such that the cleanup is still reached when all actually-added ranges are successfully removed. Link: https://lore.kernel.org/20260223201516.1517657-1-dave@stgolabs.net Fixes: 60e93dc097f7 ("device-dax: add dis-contiguous resource support") Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Ben Cheatham <benjamin.cheatham@amd.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-21Merge tag 'libnvdimm-for-7.1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull dax updates from Ira Weiny: "The series adds DAX support required for the upcoming fuse/famfs file system.[1] The support here is required because famfs is backed by devdax rather than pmem. This all lays the groundwork for using shared memory as a file system" Link: https://lore.kernel.org/all/0100019d43e5f632-f5862a3e-361c-4b54-a9a6-96c242a8f17a-000000@email.amazonses.com/ [1] * tag 'libnvdimm-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: dax/fsdev: fix uninitialized kaddr in fsdev_dax_zero_page_range() dax: export dax_dev_get() dax: Add fs_dax_get() func to prepare dax for fs-dax usage dax: Add dax_set_ops() for setting dax_operations at bind time dax: Add dax_operations for use by fs-dax on fsdev dax dax: Save the kva from memremap dax: add fsdev.c driver for fs-dax on character dax dax: Factor out dax_folio_reset_order() helper dax: move dax_pgoff_to_phys from [drivers/dax/] device.c to bus.c
2026-04-17Merge tag 'cxl-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxlLinus Torvalds
Pull CXL (Compute Express Link) updates from Dave Jiang: "The significant change of interest is the handling of soft reserved memory conflict between CXL and HMEM. In essence CXL will be the first to claim the soft reserved memory ranges that belongs to CXL and attempt to enumerate them with best effort. If CXL is not able to enumerate the ranges it will punt them to HMEM. There are also MAINTAINERS email changes from Dan Williams and Jonathan Cameron" * tag 'cxl-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (37 commits) MAINTAINERS: Update Jonathan Cameron's email address cxl/hdm: Add support for 32 switch decoders MAINTAINERS: Update address for Dan Williams tools/testing/cxl: Enable replay of user regions as auto regions cxl/region: Add a region sysfs interface for region lock status tools/testing/cxl: Test dax_hmem takeover of CXL regions tools/testing/cxl: Simulate auto-assembly failure dax/hmem: Parent dax_hmem devices dax/hmem: Fix singleton confusion between dax_hmem_work and hmem devices dax/hmem: Reduce visibility of dax_cxl coordination symbols cxl/region: Constify cxl_region_resource_contains() cxl/region: Limit visibility of cxl_region_contains_resource() dax/cxl: Fix HMEM dependencies cxl/region: Fix use-after-free from auto assembly failure cxl/core: Check existence of cxl_memdev_state in poison test cxl/core: use cleanup.h for devm_cxl_add_dax_region cxl/core/region: move dax region device logic into region_dax.c cxl/core/region: move pmem region driver logic into region_pmem.c dax/hmem, cxl: Defer and resolve Soft Reserved ownership cxl/region: Add helper to check Soft Reserved containment by CXL regions ...
2026-04-13dax/fsdev: fix uninitialized kaddr in fsdev_dax_zero_page_range()John Groves
__fsdev_dax_direct_access() returns -EFAULT without setting *kaddr when dax_pgoff_to_phys() returns -1 (pgoff out of range). The return value was ignored, leaving kaddr uninitialized before being passed to fsdev_write_dax(). Check the return value and propagate the error. Thanks to Dan Carpenter and the smatch project for reporting this. Signed-off-by: John Groves <john@groves.net> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/0100019d8262cda2-9714d31c-8fc1-4ca5-b32d-4df678240d14-000000@email.amazonses.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2026-04-05mm: rename VMA flag helpers to be more readableLorenzo Stoakes (Oracle)
Patch series "mm: vma flag tweaks". The ongoing work around introducing non-system word VMA flags has introduced a number of helper functions and macros to make life easier when working with these flags and to make conversions from the legacy use of VM_xxx flags more straightforward. This series improves these to reduce confusion as to what they do and to improve consistency and readability. Firstly the series renames vma_flags_test() to vma_flags_test_any() to make it abundantly clear that this function tests whether any of the flags are set (as opposed to vma_flags_test_all()). It then renames vma_desc_test_flags() to vma_desc_test_any() for the same reason. Note that we drop the 'flags' suffix here, as vma_desc_test_any_flags() would be cumbersome and 'test' implies a flag test. Similarly, we rename vma_test_all_flags() to vma_test_all() for consistency. Next, we have a couple of instances (erofs, zonefs) where we are now testing for vma_desc_test_any(desc, VMA_SHARED_BIT) && vma_desc_test_any(desc, VMA_MAYWRITE_BIT). This is silly, so this series introduces vma_desc_test_all() so these callers can instead invoke vma_desc_test_all(desc, VMA_SHARED_BIT, VMA_MAYWRITE_BIT). We then observe that quite a few instances of vma_flags_test_any() and vma_desc_test_any() are in fact only testing against a single flag. Using the _any() variant here is just confusing - 'any' of single item reads strangely and is liable to cause confusion. So in these instances the series reintroduces vma_flags_test() and vma_desc_test() as helpers which test against a single flag. The fact that vma_flags_t is a struct and that vma_flag_t utilises sparse to avoid confusion with vm_flags_t makes it impossible for a user to misuse these helpers without it getting flagged somewhere. The series also updates __mk_vma_flags() and functions invoked by it to explicitly mark them always inline to match expectation and to be consistent with other VMA flag helpers. It also renames vma_flag_set() to vma_flags_set_flag() (a function only used by __mk_vma_flags()) to be consistent with other VMA flag helpers. Finally it updates the VMA tests for each of these changes, and introduces explicit tests for vma_flags_test() and vma_desc_test() to assert that they behave as expected. This patch (of 6): On reflection, it's confusing to have vma_flags_test() and vma_desc_test_flags() test whether any comma-separated VMA flag bit is set, while also having vma_flags_test_all() and vma_test_all_flags() separately test whether all flags are set. Firstly, rename vma_flags_test() to vma_flags_test_any() to eliminate this confusion. Secondly, since the VMA descriptor flag functions are becoming rather cumbersome, prefer vma_desc_test*() to vma_desc_test_flags*(), and also rename vma_desc_test_flags() to vma_desc_test_any(). Finally, rename vma_test_all_flags() to vma_test_all() to keep the VMA-specific helper consistent with the VMA descriptor naming convention and to help avoid confusion vs. vma_flags_test_all(). While we're here, also update whitespace to be consistent in helper functions. Link: https://lkml.kernel.org/r/cover.1772704455.git.ljs@kernel.org Link: https://lkml.kernel.org/r/0f9cb3c511c478344fac0b3b3b0300bb95be95e9.1772704455.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Suggested-by: Pedro Falcato <pfalcato@suse.de> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Babu Moger <babu.moger@amd.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Chao Yu <chao@kernel.org> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Chunhai Guo <guochunhai@vivo.com> Cc: Damien Le Maol <dlemoal@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Gao Xiang <xiang@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hongbo Li <lihongbo22@huawei.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jeffle Xu <jefflexu@linux.alibaba.com> Cc: Johannes Thumshirn <jth@kernel.org> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naohiro Aota <naohiro.aota@wdc.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Sandeep Dhavale <dhavale@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Yue Hu <zbestahu@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-01dax/hmem: Parent dax_hmem devicesDan Williams
For test purposes it is useful to be able to determine which "hmem_platform" device is hosting a given sub-device. Register hmem devices underneath "hmem_platform". Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260327052821.440749-8-dan.j.williams@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-04-01dax/hmem: Fix singleton confusion between dax_hmem_work and hmem devicesDan Williams
dax_hmem (ab)uses a platform device to allow for a module to autoload in the presence of "Soft Reserved" resources. The dax_hmem driver had no dependencies on the "hmem_platform" device being a singleton until the recent "dax_hmem vs dax_cxl" takeover solution. Replace the layering violation of dax_hmem_work assuming that there will never be more than one "hmem_platform" device associated with a global work item with a dax_hmem local workqueue that can theoretically support any number of hmem_platform devices. Fixup the reference counting to only pin the device while it is live in the queue. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260327052821.440749-7-dan.j.williams@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-04-01dax/hmem: Reduce visibility of dax_cxl coordination symbolsDan Williams
No other module or use case should be using dax_hmem_initial_probe or dax_hmem_flush_work(). Limit their use to dax_hmem, and dax_cxl respectively. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260327052821.440749-6-dan.j.williams@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-04-01cxl/region: Constify cxl_region_resource_contains()Dan Williams
The call to cxl_region_resource_contains() in hmem_register_cxl_device() need not cast away 'const'. The problem is the usage of the bus_for_each_dev() API which does not mark its @data parameter as 'const'. Switch to bus_find_device() which does take 'const' @data, fixup cxl_region_resource_contains() and its caller. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260327052821.440749-5-dan.j.williams@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-04-01cxl/region: Limit visibility of cxl_region_contains_resource()Dan Williams
The dax_hmem dependency on cxl_region_contains_resource() is a one-off special case. It is not suitable for other use cases. Move the definition to the other CONFIG_CXL_REGION guarded definitions in drivers/cxl/cxl.h and include that by a relative path include. This matches what drivers/dax/cxl.c does for its limited private usage of CXL core symbols. Reduce the symbol export visibility from global to just dax_hmem, to further clarify its applicability. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260327052821.440749-4-dan.j.williams@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-04-01dax/cxl: Fix HMEM dependenciesDan Williams
The expectation is that DEV_DAX_HMEM=y should be disallowed if any of CXL_ACPI, or CXL_PCI are set =m. Also DEV_DAX_CXL=y should be disallowed if DEV_DAX_HMEM=m. Use "$config || !$config" syntax for each dependency. Otherwise, the invalid DEV_DAX_HMEM=m && DEV_DAX_CXL=y configuration is allowed. Lastly, dax_hmem depends on the availability of the cxl_region_contains_resource() symbol published by the cxl_core.ko module. So, also prevent DEV_DAX_HMEM from being built-in when the cxl_core module is not built-in. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260327052821.440749-3-dan.j.williams@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-03-30dax: export dax_dev_get()John Groves
famfs needs to look up a dax_device by dev_t when resolving fmap entries that reference character dax devices. Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019d311daab5-bb212f0b-4e05-4668-bf53-d76fab56be68-000000@email.amazonses.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2026-03-30dax: Add fs_dax_get() func to prepare dax for fs-dax usageJohn Groves
The fs_dax_get() function should be called by fs-dax file systems after opening a fsdev dax device. This adds holder_operations, which provides a memory failure callback path and effects exclusivity between callers of fs_dax_get(). fs_dax_get() is specific to fsdev_dax, so it checks the driver type (which required touching bus.[ch]). fs_dax_get() fails if fsdev_dax is not bound to the memory. This function serves the same role as fs_dax_get_by_bdev(), which dax file systems call after opening the pmem block device. This can't be located in fsdev.c because struct dax_device is opaque there. This will be called by fs/fuse/famfs.c in a subsequent commit. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019d311d8750-75395c22-031b-4d5f-aebe-790dca656b87-000000@email.amazonses.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2026-03-30dax: Add dax_set_ops() for setting dax_operations at bind timeJohn Groves
Add a new dax_set_ops() function that allows drivers to set the dax_operations after the dax_device has been allocated. This is needed for fsdev_dax where the operations need to be set during probe and cleared during unbind. The fsdev driver uses devm_add_action_or_reset() for cleanup consistency, avoiding the complexity of mixing devm-managed resources with manual cleanup in a remove() callback. This ensures cleanup happens automatically in the correct reverse order when the device is unbound. Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019d311d65a0-b9c1419e-f3a0-4afd-b0bd-848f18ff5950-000000@email.amazonses.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2026-03-30dax: Add dax_operations for use by fs-dax on fsdev daxJohn Groves
fsdev: Add dax_operations for use by famfs. This replicates the functionality from drivers/nvdimm/pmem.c that conventional fs-dax file systems (e.g. xfs) use to support dax read/write/mmap to a daxdev - without which famfs can't sit atop a daxdev. - These methods are based on pmem_dax_ops from drivers/nvdimm/pmem.c - fsdev_dax_direct_access() returns the hpa, pfn and kva. The kva was newly stored as dev_dax->virt_addr by dev_dax_probe(). - The hpa/pfn are used for mmap (dax_iomap_fault()), and the kva is used for read/write (dax_iomap_rw()) - fsdev_dax_recovery_write() and dev_dax_zero_page_range() have not been tested yet. I'm looking for suggestions as to how to test those. - dax-private.h: add dev_dax->cached_size, which fsdev needs to remember. The dev_dax size cannot change while a driver is bound (dev_dax_resize returns -EBUSY if dev->driver is set). Caching the size at probe time allows fsdev's direct_access path can use it without acquiring dax_dev_rwsem (which isn't exported anyway). Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019d311d415a-bd6af0fe-5445-484c-9d39-210b8170b686-000000@email.amazonses.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2026-03-30dax: Save the kva from memremapJohn Groves
Save the kva from memremap because we need it for iomap rw support. Prior to famfs, there were no iomap users of /dev/dax - so the virtual address from memremap was not needed. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019d311d1d08-dd372cb9-5934-43b8-bef8-089660d04a81-000000@email.amazonses.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2026-03-30dax: add fsdev.c driver for fs-dax on character daxJohn Groves
The new fsdev driver provides pages/folios initialized compatibly with fsdax - normal rather than devdax-style refcounting, and starting out with order-0 folios. When fsdev binds to a daxdev, it is usually (always?) switching from the devdax mode (device.c), which pre-initializes compound folios according to its alignment. Fsdev uses fsdev_clear_folio_state() to switch the folios into a fsdax-compatible state. A side effect of this is that raw mmap doesn't (can't?) work on an fsdev dax instance. Accordingly, The fsdev driver does not provide raw mmap - devices must be put in 'devdax' mode (drivers/dax/device.c) to get raw mmap capability. In this commit is just the framework, which remaps pages/folios compatibly with fsdax. Enabling dax changes: - bus.h: add DAXDRV_FSDEV_TYPE driver type - bus.c: allow DAXDRV_FSDEV_TYPE drivers to bind to daxdevs - dax.h: prototype inode_dax(), which fsdev needs Suggested-by: Dan Williams <dan.j.williams@intel.com> Suggested-by: Gregory Price <gourry@gourry.net> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019d311cf904-419e9526-bdaf-4daa-97f1-5060b31a5c9f-000000@email.amazonses.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2026-03-30dax: move dax_pgoff_to_phys from [drivers/dax/] device.c to bus.cJohn Groves
This function will be used by both device.c and fsdev.c, but both are loadable modules. Moving to bus.c puts it in core and makes it available to both. No code changes - just relocated. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: John Groves <john@groves.net> Link: https://patch.msgid.link/0100019d311c90eb-a582ff97-93ba-49f3-8140-6c5c4bf8bc62-000000@email.amazonses.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2026-03-27dax/hmem, cxl: Defer and resolve Soft Reserved ownershipSmita Koralahalli
The current probe time ownership check for Soft Reserved memory based solely on CXL window intersection is insufficient. dax_hmem probing is not always guaranteed to run after CXL enumeration and region assembly, which can lead to incorrect ownership decisions before the CXL stack has finished publishing windows and assembling committed regions. Introduce deferred ownership handling for Soft Reserved ranges that intersect CXL windows. When such a range is encountered during the initial dax_hmem probe, schedule deferred work to wait for the CXL stack to complete enumeration and region assembly before deciding ownership. Once the deferred work runs, evaluate each Soft Reserved range individually: if a CXL region fully contains the range, skip it and let dax_cxl bind. Otherwise, register it with dax_hmem. This per-range ownership model avoids the need for CXL region teardown and alloc_dax_region() resource exclusion prevents double claiming. Introduce a boolean flag dax_hmem_initial_probe to live inside device.c so it survives module reload. Ensure dax_cxl defers driver registration until dax_hmem has completed ownership resolution. dax_cxl calls dax_hmem_flush_work() before cxl_driver_register(), which both waits for the deferred work to complete and creates a module symbol dependency that forces dax_hmem.ko to load before dax_cxl. Co-developed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Link: https://patch.msgid.link/20260322195343.206900-9-Smita.KoralahalliChannabasappa@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-03-27dax: Track all dax_region allocations under a global resource treeSmita Koralahalli
Introduce a global "DAX Regions" resource root and register each dax_region->res under it via request_resource(). Release the resource on dax_region teardown. By enforcing a single global namespace for dax_region allocations, this ensures only one of dax_hmem or dax_cxl can successfully register a dax_region for a given range. Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260322195343.206900-7-Smita.KoralahalliChannabasappa@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-03-27dax/cxl, hmem: Initialize hmem early and defer dax_cxl bindingDan Williams
Move hmem/ earlier in the dax Makefile so that hmem_init() runs before dax_cxl. In addition, defer registration of the dax_cxl driver to a workqueue instead of using module_cxl_driver(). This ensures that dax_hmem has an opportunity to initialize and register its deferred callback and make ownership decisions before dax_cxl begins probing and claiming Soft Reserved ranges. Mark the dax_cxl driver as PROBE_PREFER_ASYNCHRONOUS so its probe runs out of line from other synchronous probing avoiding ordering dependencies while coordinating ownership decisions with dax_hmem. Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Tested-by: Tomasz Wolski <tomasz.wolski@fujitsu.com> Link: https://patch.msgid.link/20260322195343.206900-6-Smita.KoralahalliChannabasappa@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-03-27dax/hmem: Gate Soft Reserved deferral on DEV_DAX_CXLDan Williams
Replace IS_ENABLED(CONFIG_CXL_REGION) with IS_ENABLED(CONFIG_DEV_DAX_CXL) so that HMEM only defers Soft Reserved ranges when CXL DAX support is enabled. This makes the coordination between HMEM and the CXL stack more precise and prevents deferral in unrelated CXL configurations. Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20260322195343.206900-5-Smita.KoralahalliChannabasappa@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-03-27dax/hmem: Request cxl_acpi and cxl_pci before walking Soft Reserved rangesDan Williams
Ensure cxl_acpi has published CXL Window resources before HMEM walks Soft Reserved ranges. Replace MODULE_SOFTDEP("pre: cxl_acpi") with an explicit, synchronous request_module("cxl_acpi"). MODULE_SOFTDEP() only guarantees eventual loading, it does not enforce that the dependency has finished init before the current module runs. This can cause HMEM to start before cxl_acpi has populated the resource tree, breaking detection of overlaps between Soft Reserved and CXL Windows. Also, request cxl_pci before HMEM walks Soft Reserved ranges. Unlike cxl_acpi, cxl_pci attach is asynchronous and creates dependent devices that trigger further module loads. Asynchronous probe flushing (wait_for_device_probe()) is added later in the series in a deferred context before HMEM makes ownership decisions for Soft Reserved ranges. Add an additional explicit Kconfig ordering so that CXL_ACPI and CXL_PCI must be initialized before DEV_DAX_HMEM. This prevents HMEM from consuming Soft Reserved ranges before CXL drivers have had a chance to claim them. Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Tested-by: Tomasz Wolski <tomasz.wolski@fujitsu.com> Link: https://patch.msgid.link/20260322195343.206900-4-Smita.KoralahalliChannabasappa@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-03-27dax/hmem: Factor HMEM registration into __hmem_register_device()Smita Koralahalli
Separate the CXL overlap check from the HMEM registration path and keep the platform-device setup in a dedicated __hmem_register_device(). This makes hmem_register_device() the policy entry point for deciding whether a range should be deferred to CXL, while __hmem_register_device() handles the HMEM registration flow. No functional changes. Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260322195343.206900-3-Smita.KoralahalliChannabasappa@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-03-27dax/bus: Use dax_region_put() in alloc_dax_region() error pathSmita Koralahalli
alloc_dax_region() calls kref_init() on the dax_region early in the function, but the error path for sysfs_create_groups() failure uses kfree() directly to free the dax_region. This bypasses the kref lifecycle. Use dax_region_put() instead to handle kref lifecycle correctly. Suggested-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260322195343.206900-2-Smita.KoralahalliChannabasappa@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-02-21Convert 'alloc_flex' family to use the new default GFP_KERNEL argumentLinus Torvalds
This is the exact same thing as the 'alloc_obj()' version, only much smaller because there are a lot fewer users of the *alloc_flex() interface. As with alloc_obj() version, this was done entirely with mindless brute force, using the same script, except using 'flex' in the pattern rather than 'objs*'. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-18Merge tag 'mm-stable-2026-02-18-19-48' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "mm/vmscan: fix demotion targets checks in reclaim/demotion" fixes a couple of issues in the demotion code - pages were failed demotion and were finding themselves demoted into disallowed nodes (Bing Jiao) - "Remove XA_ZERO from error recovery of dup_mmap()" fixes a rare mapledtree race and performs a number of cleanups (Liam Howlett) - "mm: add bitmap VMA flag helpers and convert all mmap_prepare to use them" implements a lot of cleanups following on from the conversion of the VMA flags into a bitmap (Lorenzo Stoakes) - "support batch checking of references and unmapping for large folios" implements batching to greatly improve the performance of reclaiming clean file-backed large folios (Baolin Wang) - "selftests/mm: add memory failure selftests" does as claimed (Miaohe Lin) * tag 'mm-stable-2026-02-18-19-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (36 commits) mm/page_alloc: clear page->private in free_pages_prepare() selftests/mm: add memory failure dirty pagecache test selftests/mm: add memory failure clean pagecache test selftests/mm: add memory failure anonymous page test mm: rmap: support batched unmapping for file large folios arm64: mm: implement the architecture-specific clear_flush_young_ptes() arm64: mm: support batch clearing of the young flag for large folios arm64: mm: factor out the address and ptep alignment into a new helper mm: rmap: support batched checks of the references for large folios tools/testing/vma: add VMA userland tests for VMA flag functions tools/testing/vma: separate out vma_internal.h into logical headers tools/testing/vma: separate VMA userland tests into separate files mm: make vm_area_desc utilise vma_flags_t only mm: update all remaining mmap_prepare users to use vma_flags_t mm: update shmem_[kernel]_file_*() functions to use vma_flags_t mm: update secretmem to use VMA flags on mmap_prepare mm: update hugetlbfs to use VMA flags on mmap_prepare mm: add basic VMA flag operation helper functions tools: bitmap: add missing bitmap_[subset(), andnot()] mm: add mk_vma_flags() bitmap flag macro helper ...
2026-02-12Merge tag 'cxl-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxlLinus Torvalds
Pull CXL updates from Dave Jiang: - Introduce cxl_memdev_attach and pave way for soft reserved handling, type2 accelerator enabling, and LSA 2.0 enabling. All these series require the endpoint driver to settle before continuing the memdev driver probe. - Address CXL port error protocol handling and reporting. The large patch series was split into three parts. The first two parts are included here with the final part coming later. The first part consists of a series of code refactoring to PCI AER sub-system that addresses CXL and also CXL RAS code to prepare for port error handling. The second part refactors the CXL code to move management of component registers to cxl_port objects to allow all CXL AER errors to be handled through the cxl_port hierarchy. - Provide AMD Zen5 platform address translation for CXL using ACPI PRMT. This includes a conventions document to explain why this is needed and how it's implemented. - Misc CXL patches of fixes, cleanups, and updates. Including CXL address translation for unaligned MOD3 regions. [ TLA service: CXL is "Compute Express Link" ] * tag 'cxl-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (59 commits) cxl: Disable HPA/SPA translation handlers for Normalized Addressing cxl/region: Factor out code into cxl_region_setup_poison() cxl/atl: Lock decoders that need address translation cxl: Enable AMD Zen5 address translation using ACPI PRMT cxl/acpi: Prepare use of EFI runtime services cxl: Introduce callback for HPA address ranges translation cxl/region: Use region data to get the root decoder cxl/region: Add @hpa_range argument to function cxl_calc_interleave_pos() cxl/region: Separate region parameter setup and region construction cxl: Simplify cxl_root_ops allocation and handling cxl/region: Store HPA range in struct cxl_region cxl/region: Store root decoder in struct cxl_region cxl/region: Rename misleading variable name @hpa to @hpa_range Documentation/driver-api/cxl: ACPI PRM Address Translation Support and AMD Zen5 enablement cxl, doc: Moving conventions in separate files cxl, doc: Remove isonum.txt inclusion cxl/port: Unify endpoint and switch port lookup cxl/port: Move endpoint component register management to cxl_port cxl/port: Map Port RAS registers cxl/port: Move dport RAS setup to dport add time ...
2026-02-12mm: update all remaining mmap_prepare users to use vma_flags_tLorenzo Stoakes
We will be shortly removing the vm_flags_t field from vm_area_desc so we need to update all mmap_prepare users to only use the dessc->vma_flags field. This patch achieves that and makes all ancillary changes required to make this possible. This lays the groundwork for future work to eliminate the use of vm_flags_t in vm_area_desc altogether and more broadly throughout the kernel. While we're here, we take the opportunity to replace VM_REMAP_FLAGS with VMA_REMAP_FLAGS, the vma_flags_t equivalent. No functional changes intended. Link: https://lkml.kernel.org/r/fb1f55323799f09fe6a36865b31550c9ec67c225.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Damien Le Moal <dlemoal@kernel.org> [zonefs] Acked-by: "Darrick J. Wong" <djwong@kernel.org> Acked-by: Pedro Falcato <pfalcato@suse.de> 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@nvidia.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-16dax/hmem, e820, resource: Defer Soft Reserved insertion until hmem is readyDan Williams
Insert Soft Reserved memory into a dedicated soft_reserve_resource tree instead of the iomem_resource tree at boot. Delay publishing these ranges into the iomem hierarchy until ownership is resolved and the HMEM path is ready to consume them. Publishing Soft Reserved ranges into iomem too early conflicts with CXL hotplug and prevents region assembly when those ranges overlap CXL windows. Follow up patches will reinsert Soft Reserved ranges into iomem after CXL window publication is complete and HMEM is ready to claim the memory. This provides a cleaner handoff between EFI-defined memory ranges and CXL resource management without trimming or deleting resources later. In the meantime "Soft Reserved" resources will no longer appear in /proc/iomem, only their results. I.e. with "memmap=4G%4G+0xefffffff" Before: 100000000-1ffffffff : Soft Reserved 100000000-1ffffffff : dax1.0 100000000-1ffffffff : System RAM (kmem) After: 100000000-1ffffffff : dax1.0 100000000-1ffffffff : System RAM (kmem) The expectation is that this does not lead to a user visible regression because the dax1.0 device is created in both instances. Co-developed-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> [Smita: incorporate feedback from x86 maintainer review] Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Link: https://patch.msgid.link/20251120031925.87762-2-Smita.KoralahalliChannabasappa@amd.com [djbw: cleanups and clarifications] Link: https://lore.kernel.org/69443f707b025_1cee10022@dwillia2-mobl4.notmuch Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-01-14drivers/dax: add some missing kerneldoc comment fields for struct dev_daxJohn Groves
Add the missing @align and @memmap_on_memory fields to kerneldoc comment header for struct dev_dax. Also, some other fields were followed by '-' and others by ':'. Fix all to be ':' for actual kerneldoc compliance. Link: https://lkml.kernel.org/r/20260110191804.5739-1-john@groves.net Fixes: 33cf94d71766 ("device-dax: make align a per-device property") Fixes: 4eca0ef49af9 ("dax/kmem: allow kmem to add memory with memmap_on_memory") Signed-off-by: John Groves <john@groves.net> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-12-05Merge tag 'mm-stable-2025-12-03-21-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki) Rework the vmalloc() code to support non-blocking allocations (GFP_ATOIC, GFP_NOWAIT) "ksm: fix exec/fork inheritance" (xu xin) Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited across fork/exec "mm/zswap: misc cleanup of code and documentations" (SeongJae Park) Some light maintenance work on the zswap code "mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira) Enhance the /sys/kernel/debug/page_owner debug feature by adding unique identifiers to differentiate the various stack traces so that userspace monitoring tools can better match stack traces over time "mm/page_alloc: pcp->batch cleanups" (Joshua Hahn) Minor alterations to the page allocator's per-cpu-pages feature "Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra) Address a scalability issue in userfaultfd's UFFDIO_MOVE operation "kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov) "drivers/base/node: fold node register and unregister functions" (Donet Tom) Clean up the NUMA node handling code a little "mm: some optimizations for prot numa" (Kefeng Wang) Cleanups and small optimizations to the NUMA allocation hinting code "mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn) Address long lock hold times at boot on large machines. These were causing (harmless) softlockup warnings "optimize the logic for handling dirty file folios during reclaim" (Baolin Wang) Remove some now-unnecessary work from page reclaim "mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park) Enhance the DAMOS auto-tuning feature "mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan) Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace configuration "expand mmap_prepare functionality, port more users" (Lorenzo Stoakes) Enhance the new(ish) file_operations.mmap_prepare() method and port additional callsites from the old ->mmap() over to ->mmap_prepare() "Fix stale IOTLB entries for kernel address space" (Lu Baolu) Fix a bug (and possible security issue on non-x86) in the IOMMU code. In some situations the IOMMU could be left hanging onto a stale kernel pagetable entry "mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang) Clean up and optimize the folio splitting code "mm, swap: misc cleanup and bugfix" (Kairui Song) Some cleanups and a minor fix in the swap discard code "mm/damon: misc documentation fixups" (SeongJae Park) "mm/damon: support pin-point targets removal" (SeongJae Park) Permit userspace to remove a specific monitoring target in the middle of the current targets list "mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo) A couple of cleanups related to mm header file inclusion "mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He) improve the selection of swap devices for NUMA machines "mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista) Change the memory block labels from macros to enums so they will appear in kernel debug info "ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes) Address an inefficiency when KSM unmerges an address range "mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park) Fix leaks and unhandled malloc() failures in DAMON userspace unit tests "some cleanups for pageout()" (Baolin Wang) Clean up a couple of minor things in the page scanner's writeback-for-eviction code "mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu) Move hugetlb's sysfs/sysctl handling code into a new file "introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes) Make the VMA guard regions available in /proc/pid/smaps and improves the mergeability of guarded VMAs "mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes) Reduce mmap lock contention for callers performing VMA guard region operations "vma_start_write_killable" (Matthew Wilcox) Start work on permitting applications to be killed when they are waiting on a read_lock on the VMA lock "mm/damon/tests: add more tests for online parameters commit" (SeongJae Park) Add additional userspace testing of DAMON's "commit" feature "mm/damon: misc cleanups" (SeongJae Park) "make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes) Address the possible loss of a VMA's VM_SOFTDIRTY flag when that VMA is merged with another "mm: support device-private THP" (Balbir Singh) Introduce support for Transparent Huge Page (THP) migration in zone device-private memory "Optimize folio split in memory failure" (Zi Yan) "mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang) Some more cleanups in the folio splitting code "mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes) Clean up our handling of pagetable leaf entries by introducing the concept of 'software leaf entries', of type softleaf_t "reparent the THP split queue" (Muchun Song) Reparent the THP split queue to its parent memcg. This is in preparation for addressing the long-standing "dying memcg" problem, wherein dead memcg's linger for too long, consuming memory resources "unify PMD scan results and remove redundant cleanup" (Wei Yang) A little cleanup in the hugepage collapse code "zram: introduce writeback bio batching" (Sergey Senozhatsky) Improve zram writeback efficiency by introducing batched bio writeback support "memcg: cleanup the memcg stats interfaces" (Shakeel Butt) Clean up our handling of the interrupt safety of some memcg stats "make vmalloc gfp flags usage more apparent" (Vishal Moola) Clean up vmalloc's handling of incoming GFP flags "mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang) Teach soft dirty and userfaultfd write protect tracking to use RISC-V's Svrsw60t59b extension "mm: swap: small fixes and comment cleanups" (Youngjun Park) Fix a small bug and clean up some of the swap code "initial work on making VMA flags a bitmap" (Lorenzo Stoakes) Start work on converting the vma struct's flags to a bitmap, so we stop running out of them, especially on 32-bit "mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park) Address a possible bug in the swap discard code and clean things up a little [ This merge also reverts commit ebb9aeb980e5 ("vfio/nvgrace-gpu: register device memory for poison handling") because it looks broken to me, I've asked for clarification - Linus ] * tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) mm: fix vma_start_write_killable() signal handling mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate mm/swapfile: fix list iteration when next node is removed during discard fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling mm/kfence: add reboot notifier to disable KFENCE on shutdown memcg: remove inc/dec_lruvec_kmem_state helpers selftests/mm/uffd: initialize char variable to Null mm: fix DEBUG_RODATA_TEST indentation in Kconfig mm: introduce VMA flags bitmap type tools/testing/vma: eliminate dependency on vma->__vm_flags mm: simplify and rename mm flags function for clarity mm: declare VMA flags by bit zram: fix a spelling mistake mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity mm/vmscan: skip increasing kswapd_failures when reclaim was boosted pagemap: update BUDDY flag documentation mm: swap: remove scan_swap_map_slots() references from comments mm: swap: change swap_alloc_slow() to void mm, swap: remove redundant comment for read_swap_cache_async mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational ...