summaryrefslogtreecommitdiff
path: root/Documentation/admin-guide/blockdev
AgeCommit message (Collapse)Author
22 hoursMerge tag 'mm-stable-2026-08-26-15-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff" (Lorenzo Stoakes) Index MAP_PRIVATE file-backed folios by their anonymous page offset to resolve confusion around reverse mapping for zeroed and CoW'd file-backed memory. Use this new VMA anonymous page offset tracking to eliminate index conflicts and lay the foundation for scalable CoW performance improvements. - "promote mapped executable folios after first usage for MGLRU" (Baolin Wang) Make MGLRU's protection of mapped executable file folios more reliable. Follow the classical LRU's logic, promoting mapped executable file folios after their first usage to give executable code a better chance to stay in memory and improve workload performance. - "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong Chen) Fix per-node proactive reclaim interface's ignoring the swappiness parameter when CONFIG_MEMCG is disabled by consolidating sc_swappiness() into a single function that checks proactive_swappiness regardless of kernel configuration. - "mm/vmscan: reduce lru_lock contention via vmstat-derived scan-balance cost" (Usama Arif) Reduce lru_lock contention in the reclaim path by deriving scan-balance costs from vmstat counters rather than lock-acquired producer updates. Read and decay these cost signals on the reclaim side under a dedicated per-lruvec lock, reducing total LRU lock wait time by over 60% without impacting scan throughput. - "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky) Fix two low-risk zram bugs which Sashiko spotted in drive-by review. - "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's memcg" (Zi Yan) Fix xas_split_alloc() by enabling target folio memcg charging during splits and adding the missing __GFP_ACCOUNT flag for proper XArray node memory accounting. - "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick) Replace hardcoded binary names in selftests/mm/.gitignore with a generic pattern-matching rule to automatically ignore generated test files and avoid manual updates when adding new tests. - "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon) Make the incompatibility between FLATMEM and NUMA explicit in mm/Kconfig and remove the unused pgdat_page_ext_init() function. - "zram: fix zstd error paths and add parameter validation" (Haoqin Huang) Clean up zram compression backends by removing redundant error cleanup, adding parameter and dictionary validation, auto-prefixing algorithm error logs, and resetting parameters prior to reinitialization. - "zram: fix stale scan bounds after reinitialization" (Longlong Xia) Prevent out-of-bounds slot accesses during concurrent zram resets by moving table scan bound calculations under dev_lock in writeback_store() and read_block_state(). - "add anon mTHP collapse test cases" (Baolin Wang) Extend selftests helper functions to support arbitrary page orders and add new test cases and options for mTHP collapse in khugepaged. - "selftests/mm: Handle unsupported and transient test conditions" (Muhammad Usama Anjum) Update MM selftests to report a SKIP status instead of a failure when required kernel or filesystem features are unsupported, while adding retry logic for transient page migration errors. - "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia) Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled and extend shrink_memcg() to support batch writeback for improved writeback efficiency. - "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren Baghdasaryan) Introduce an IOCTL-based binary interface for memory allocation profiling that enables kernel-side filtering before per-CPU counter aggregation. This eliminates the text-parsing overhead of /proc/allocinfo and provides up to a 20x speedup by transferring only filtered allocation data to userspace. - "better block swap batching and a different take on swap_ops v5" (Christoph Hellwig) Refactor block swap I/O to use swap_iocb for batching instead of single-bio requests and rebase the swap_ops interface, achieving faster swap throughput during kernel builds. - "mm: kmemleak: reduce transient false positives by confirming leaks" (Catalin Marinas) Reduce false-positive kmemleak reports by combining two kmemleak enhancements that add a second confirmation scan and a configurable minimum unreferenced scan count module parameter. - "mm: kmemleak: default min_unref_scans to 2 for verbose kernels" (Breno Leitao) Auto-scanning kernels can generate false-positive memory leak reports on single scans, so this patch defaults min_unref_scans to 2 when CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second confirming scan. - "swap_ops updates" (Christoph Hellwig) Batching I/O for synchronous swap devices causes performance regressions and filesystem-based swap suffers from double-indirection overhead. This series resolves both issues by reintroducing per-folio writes for synchronous swap and allowing filesystems to directly export their own swap_ops. - "mm/khugepaged: several cleanups" (Nico Pache) khugepaged accumulated redundant state-checking patterns and outdated comments following mTHP integration. Introduce dedicated helpers for PTE validation and event counting while refreshing the internal documentation. - "maple_tree: lock checking and clean ups" (Liam Howlett) Syzbot reports incorrectly blame memory management exit paths for locking bugs, maple tree erase operations risk allocation failures without gfp flags and internal documentation lacks clarity. Improve lock error detection, update docs, fix race and allocation edge cases and optimize erase allocations using a fallback to GFP_KERNEL | GFP_NOFAIL. * tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (172 commits) selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC memcg: move LRU size accounting on reparenting instead of copying it mm/vmscan: fix comment logic in balance_pgdat maple_tree: add helper mas_make_walkable() maple_tree: avoid extra gap calculation maple_tree: fix argument name in header maple_tree: change two GFP flags in tests maple_tree: document erase and allocations better maple_tree: avoid mas_erase() and mtree_erase() failures maple_tree: document that erase may use GFP_KERNEL for allocations maple_tree: catch race in mas_alloc_cyclic() maple_tree: add bulk parent set helper maple_tree: micro optimisation of mas_wr_store_type() maple_tree: optimise mas_wr_node_store() when not in rcu mode maple_tree: use prefetched value in mas_wr_store_type() maple_tree: clarify comments on mas_nomem() maple_tree: drop MAPLE_ALLOC_SLOTS maple_tree: drop dead code from mas_extend_spanning_null() maple_tree: documentation fix maple_tree: add write lock checking with lockdep sequence numbers ...
4 daysDocumentation: zram: correct algo parameters configuration documentationSergey Senozhatsky
zram has always reset all previously set parameters for the given algorithm in comp_params_store(). Make documentation more clear and explicitly state that all relevant/necessary parameters should be set in one configuration write. Link: https://lore.kernel.org/20260730075158.1339787-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
8 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 ...
2026-08-06Documentation: zram: remove sections numberingSergey Senozhatsky
Those numbers are difficult to maintain and in fact we can refer to sections by their names (in html). Link: https://lore.kernel.org/20260728021229.181627-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: SJ Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04Documentation: block: zloop: clarify capacity alignmentXu Rao
zloop divides the requested capacity by the zone size to determine the number of zones. Since it uses one zone size for all zones, a smaller last zone is not supported and an unaligned capacity is rounded down. The capacity_mb description incorrectly states that the capacity is rounded up. Correct it to document the actual behavior. Fixes: 9e4f11c1228c ("Documentation: Document the new zoned loop block device driver") Suggested-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Xu Rao <raoxu@uniontech.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/4659F8F0C6C328EA+20260804052942.1186727-1-raoxu@uniontech.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-04zloop: truncate finished zones to zone capacityXu Rao
The size of a sequential zone backing file records the amount of data written and is used to restore the zone state. A backing file whose size is equal to the zone capacity is restored as a full zone, while a file larger than the zone capacity is rejected as invalid. However, zloop_finish_zone() currently truncates the backing file to the zone size. For devices with a reduced zone capacity, finishing a zone therefore creates a backing file larger than the zone capacity. After the device is removed and later re-added, that zone file is rejected instead of being restored as a full zone. Truncate finished sequential zones to the zone capacity, matching the persistent representation accepted by zloop_update_seq_zone() for a full zone. Suggested-by: Damien Le Moal <dlemoal@kernel.org> Fixes: eb0570c7df23 ("block: new zoned loop block device driver") Cc: stable@vger.kernel.org Signed-off-by: Xu Rao <raoxu@uniontech.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://patch.msgid.link/B39E5FD81D1A07F4+20260804023403.939767-1-raoxu@uniontech.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-04-15Merge tag 'mm-stable-2026-04-13-21-45' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "maple_tree: Replace big node with maple copy" (Liam Howlett) Mainly prepararatory work for ongoing development but it does reduce stack usage and is an improvement. - "mm, swap: swap table phase III: remove swap_map" (Kairui Song) Offers memory savings by removing the static swap_map. It also yields some CPU savings and implements several cleanups. - "mm: memfd_luo: preserve file seals" (Pratyush Yadav) File seal preservation to LUO's memfd code - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan Chen) Additional userspace stats reportng to zswap - "arch, mm: consolidate empty_zero_page" (Mike Rapoport) Some cleanups for our handling of ZERO_PAGE() and zero_pfn - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu Han) A robustness improvement and some cleanups in the kmemleak code - "Improve khugepaged scan logic" (Vernon Yang) Improve khugepaged scan logic and reduce CPU consumption by prioritizing scanning tasks that access memory frequently - "Make KHO Stateless" (Jason Miu) Simplify Kexec Handover by transitioning KHO from an xarray-based metadata tracking system with serialization to a radix tree data structure that can be passed directly to the next kernel - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas Ballasi and Steven Rostedt) Enhance vmscan's tracepointing - "mm: arch/shstk: Common shadow stack mapping helper and VM_NOHUGEPAGE" (Catalin Marinas) Cleanup for the shadow stack code: remove per-arch code in favour of a generic implementation - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin) Fix a WARN() which can be emitted the KHO restores a vmalloc area - "mm: Remove stray references to pagevec" (Tal Zussman) Several cleanups, mainly udpating references to "struct pagevec", which became folio_batch three years ago - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl Shutsemau) Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail pages encode their relationship to the head page - "mm/damon/core: improve DAMOS quota efficiency for core layer filters" (SeongJae Park) Improve two problematic behaviors of DAMOS that makes it less efficient when core layer filters are used - "mm/damon: strictly respect min_nr_regions" (SeongJae Park) Improve DAMON usability by extending the treatment of the min_nr_regions user-settable parameter - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka) The proper fix for a previously hotfixed SMP=n issue. Code simplifications and cleanups ensued - "mm: cleanups around unmapping / zapping" (David Hildenbrand) A bunch of cleanups around unmapping and zapping. Mostly simplifications, code movements, documentation and renaming of zapping functions - "support batched checking of the young flag for MGLRU" (Baolin Wang) Batched checking of the young flag for MGLRU. It's part cleanups; one benchmark shows large performance benefits for arm64 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner) memcg cleanup and robustness improvements - "Allow order zero pages in page reporting" (Yuvraj Sakshith) Enhance free page reporting - it is presently and undesirably order-0 pages when reporting free memory. - "mm: vma flag tweaks" (Lorenzo Stoakes) Cleanup work following from the recent conversion of the VMA flags to a bitmap - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae Park) Add some more developer-facing debug checks into DAMON core - "mm/damon: test and document power-of-2 min_region_sz requirement" (SeongJae Park) An additional DAMON kunit test and makes some adjustments to the addr_unit parameter handling - "mm/damon/core: make passed_sample_intervals comparisons overflow-safe" (SeongJae Park) Fix a hard-to-hit time overflow issue in DAMON core - "mm/damon: improve/fixup/update ratio calculation, test and documentation" (SeongJae Park) A batch of misc/minor improvements and fixups for DAMON - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David Hildenbrand) Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code movement was required. - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky) A somewhat random mix of fixups, recompression cleanups and improvements in the zram code - "mm/damon: support multiple goal-based quota tuning algorithms" (SeongJae Park) Extend DAMOS quotas goal auto-tuning to support multiple tuning algorithms that users can select - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao) Fix the khugpaged sysfs handling so we no longer spam the logs with reams of junk when starting/stopping khugepaged - "mm: improve map count checks" (Lorenzo Stoakes) Provide some cleanups and slight fixes in the mremap, mmap and vma code - "mm/damon: support addr_unit on default monitoring targets for modules" (SeongJae Park) Extend the use of DAMON core's addr_unit tunable - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache) Cleanups to khugepaged and is a base for Nico's planned khugepaged mTHP support - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand) Code movement and cleanups in the memhotplug and sparsemem code - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup CONFIG_MIGRATION" (David Hildenbrand) Rationalize some memhotplug Kconfig support - "change young flag check functions to return bool" (Baolin Wang) Cleanups to change all young flag check functions to return bool - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh Law and SeongJae Park) Fix a few potential DAMON bugs - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo Stoakes) Convert a lot of the existing use of the legacy vm_flags_t data type to the new vma_flags_t type which replaces it. Mainly in the vma code. - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes) Expand the mmap_prepare functionality, which is intended to replace the deprecated f_op->mmap hook which has been the source of bugs and security issues for some time. Cleanups, documentation, extension of mmap_prepare into filesystem drivers - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes) Simplify and clean up zap_huge_pmd(). Additional cleanups around vm_normal_folio_pmd() and the softleaf functionality are performed. * tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm: fix deferred split queue races during migration mm/khugepaged: fix issue with tracking lock mm/huge_memory: add and use has_deposited_pgtable() mm/huge_memory: add and use normal_or_softleaf_folio_pmd() mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio() mm/huge_memory: separate out the folio part of zap_huge_pmd() mm/huge_memory: use mm instead of tlb->mm mm/huge_memory: remove unnecessary sanity checks mm/huge_memory: deduplicate zap deposited table call mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE() mm/huge_memory: add a common exit path to zap_huge_pmd() mm/huge_memory: handle buggy PMD entry in zap_huge_pmd() mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc mm/huge: avoid big else branch in zap_huge_pmd() mm/huge_memory: simplify vma_is_specal_huge() mm: on remap assert that input range within the proposed VMA mm: add mmap_action_map_kernel_pages[_full]() uio: replace deprecated mmap hook with mmap_prepare in uio_info drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare mm: allow handling of stacked mmap_prepare hooks in more drivers ...
2026-04-13Merge tag 'for-7.1/block-20260411' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull block updates from Jens Axboe: - Add shared memory zero-copy I/O support for ublk, bypassing per-I/O copies between kernel and userspace by matching registered buffer PFNs at I/O time. Includes selftests. - Refactor bio integrity to support filesystem initiated integrity operations and arbitrary buffer alignment. - Clean up bio allocation, splitting bio_alloc_bioset() into clear fast and slow paths. Add bio_await() and bio_submit_or_kill() helpers, unify synchronous bi_end_io callbacks. - Fix zone write plug refcount handling and plug removal races. Add support for serializing zone writes at QD=1 for rotational zoned devices, yielding significant throughput improvements. - Add SED-OPAL ioctls for Single User Mode management and a STACK_RESET command. - Add io_uring passthrough (uring_cmd) support to the BSG layer. - Replace pp_buf in partition scanning with struct seq_buf. - zloop improvements and cleanups. - drbd genl cleanup, switching to pre_doit/post_doit. - NVMe pull request via Keith: - Fabrics authentication updates - Enhanced block queue limits support - Workqueue usage updates - A new write zeroes device quirk - Tagset cleanup fix for loop device - MD pull requests via Yu Kuai: - Fix raid5 soft lockup in retry_aligned_read() - Fix raid10 deadlock with check operation and nowait requests - Fix raid1 overlapping writes on writemostly disks - Fix sysfs deadlock on array_state=clear - Proactive RAID-5 parity building with llbitmap, with write_zeroes_unmap optimization for initial sync - Fix llbitmap barrier ordering, rdev skipping, and bitmap_ops version mismatch fallback - Fix bcache use-after-free and uninitialized closure - Validate raid5 journal metadata payload size - Various cleanups - Various other fixes, improvements, and cleanups * tag 'for-7.1/block-20260411' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (146 commits) ublk: fix tautological comparison warning in ublk_ctrl_reg_buf scsi: bsg: fix buffer overflow in scsi_bsg_uring_cmd() block: refactor blkdev_zone_mgmt_ioctl MAINTAINERS: update ublk driver maintainer email Documentation: ublk: address review comments for SHMEM_ZC docs ublk: allow buffer registration before device is started ublk: replace xarray with IDA for shmem buffer index allocation ublk: simplify PFN range loop in __ublk_ctrl_reg_buf ublk: verify all pages in multi-page bvec fall within registered range ublk: widen ublk_shmem_buf_reg.len to __u64 for 4GB buffer support xfs: use bio_await in xfs_zone_gc_reset_sync block: add a bio_submit_or_kill helper block: factor out a bio_await helper block: unify the synchronous bi_end_io callbacks xfs: fix number of GC bvecs selftests/ublk: add read-only buffer registration test selftests/ublk: add filesystem fio verify test for shmem_zc selftests/ublk: add hugetlbfs shmem_zc test for loop target selftests/ublk: add shared memory zero-copy test selftests/ublk: add UBLK_F_SHMEM_ZC support for loop target ...
2026-04-05zram: remove chained recompressionSergey Senozhatsky
Chained recompression has unpredictable behavior and is not useful in practice. First, systems usually configure just one alternative recompression algorithm, which has slower compression/decompression but better compression ratio. A single alternative algorithm doesn't need chaining. Second, even with multiple recompression algorithms, chained recompression is suboptimal. If a lower priority algorithm succeeds, the page is never attempted with a higher priority algorithm, leading to worse memory savings. If a lower priority algorithm fails, the page is still attempted with a higher priority algorithm, wasting resources on the failed lower priority attempt. In either case, the system would be better off targeting a specific priority directly. Chained recompression also significantly complicates the code. Remove it. Link: https://lkml.kernel.org/r/20260311084312.1766036-6-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Brian Geffon <bgeffon@google.com> Cc: gao xu <gaoxu2@honor.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05zram: update recompression documentationSergey Senozhatsky
Emphasize usage of the `priority` parameter for recompression and explain why `algo` parameter can lead to unexpected behavior and thus is not recommended. Link: https://lkml.kernel.org/r/20260311084312.1766036-5-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Brian Geffon <bgeffon@google.com> Cc: gao xu <gaoxu2@honor.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-31zloop: add max_open_zones optionDamien Le Moal
Introduce the new max_open_zones option to allow specifying a limit on the maximum number of open zones of a zloop device. This change allows creating a zloop device that can more closely mimick the characteristics of a physical SMR drive. When set to a non zero value, only up to max_open_zones zones can be in the implicit open (BLK_ZONE_COND_IMP_OPEN) and explicit open (BLK_ZONE_COND_EXP_OPEN) conditions at any time. The transition to the implicit open condition of a zone on a write operation can result in an implicit close of an already implicitly open zone. This is handled in the function zloop_do_open_zone(). This function also handles transitions to the explicit open condition. Implicit close transitions are handled using an LRU ordered list of open zones which is managed using the helper functions zloop_lru_rotate_open_zone() and zloop_lru_remove_open_zone(). Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260326203245.946830-1-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-03-25zloop: forget write cache on force removalChristoph Hellwig
Add a new options that causes zloop to truncate the zone files to the write pointer value recorded at the last cache flush to simulate unclean shutdowns. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://patch.msgid.link/20260323071156.2940772-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-03-04zram: rename writeback_compressed device attrSergey Senozhatsky
Rename writeback_compressed attr to compressed_writeback to avoid possible confusion and have more natural naming. writeback_compressed may look like an alternative version of writeback while in fact writeback_compressed only sets a writeback property. Make this distinction more clear with a new compressed_writeback name. This updates a feature which is new in 7.0-rcX. Link: https://lkml.kernel.org/r/20260226025429.1042083-1-senozhatsky@chromium.org Fixes: 4c1d61389e8e ("zram: introduce writeback_compressed device attribute") Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Suggested-by: Minchan Kim <minchan@kernel.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Brian Geffon <bgeffon@google.com> Cc: Richard Chang <richardycc@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: "Christoph Böhmwalder" <christoph.boehmwalder@linbit.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lars Ellenberg <lars.ellenberg@linbit.com> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20zram: document writeback_batch_sizeSergey Senozhatsky
Add missing writeback_batch_size documentation. Link: https://lkml.kernel.org/r/20251201094754.4149975-4-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Brian Geffon <bgeffon@google.com> Cc: David Stevens <stevensd@google.com> Cc: Minchan Kim <minchan@google.com> Cc: Richard Chang <richardycc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20zram: introduce writeback_compressed device attributeRichard Chang
Introduce witeback_compressed device attribute to toggle compressed writeback (decompression on demand) feature. [senozhatsky@chromium.org: rewrote original patch, added documentation] Link: https://lkml.kernel.org/r/20251201094754.4149975-3-senozhatsky@chromium.org Signed-off-by: Richard Chang <richardycc@google.com> Co-developed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Brian Geffon <bgeffon@google.com> Cc: David Stevens <stevensd@google.com> Cc: Minchan Kim <minchan@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-12-15Documentation: admin-guide: blockdev: replace zone_capacity with ↵Yongpeng Yang
zone_capacity_mb when creating devices The "zone_capacity=%umb" option is no longer used. The effective option is now "zone_capacity_mb=%u", so update the documentation accordingly. Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-17Documentation: admin-guide: blockdev: update zloop parametersDamien Le Moal
In Documentation/admin-guide/blockdev/zoned_loop.rst, add the description of the zone_append and ordered_zone_append configuration arguments of zloop "add" command (device creation). Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-10-03Merge tag 'docs-6.18' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a relatively busy cycle in docsland, with changes all over: - Bring the kernel memory-model docs into the Sphinx build in the "literal include" mode. - Lots of build-infrastructure work, further cleaning up long-term kernel-doc technical debt. The sphinx-pre-install tool has been converted to Python and updated for current systems. - A new tool to detect when documents have been moved and generate HTML redirects; this can be used on kernel.org (or any other site hosting the rendered docs) to avoid breaking links. - Automated processing of the YAML files describing the netlink protocol. - A significant update of the maintainer's PGP guide. ... and a seemingly endless series of typo fixes, build-problem fixes, etc" * tag 'docs-6.18' of git://git.lwn.net/linux: (193 commits) Documentation/features: Update feature lists for 6.17-rc7 docs: remove cdomain.py Documentation/process: submitting-patches: fix typo in "were do" docs: dev-tools/lkmm: Fix typo of missing file extension Documentation: trace: histogram: Convert ftrace docs cross-reference Documentation: trace: histogram-design: Wrap introductory note in note:: directive Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram Documentation: trace: histogram-design: Trim trailing vertices in diagram explanation text Documentation: trace: histogram: Fix histogram trigger subsection number order docs: driver-api: fix spelling of "buses". Documentation: fbcon: Use admonition directives Documentation: fbcon: Reindent 8th step of attach/detach/unload Documentation: fbcon: Add boot options and attach/detach/unload section headings docs: filesystems: sysfs: add remaining top level sysfs directory descriptions docs: filesystems: sysfs: clarify symlink destinations in dev and bus/devices descriptions docs: filesystems: sysfs: remove top level sysfs net directory docs: maintainer: Fix ambiguous subheading formatting docs: kdoc: a few more dump_typedef() tweaks docs: kdoc: remove redundant comment stripping in dump_typedef() docs: kdoc: remove some dead code in dump_typedef() ...
2025-08-18Documentation: Fix admin-guide typosBjorn Helgaas
Fix typos. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250813200526.290420-4-helgaas@kernel.org
2025-08-13Docs: admin-guide: Correct spelling mistakeErick Karanja
Fix spelling mistake directoy to directory Reported-by: codespell Signed-off-by: Erick Karanja <karanja99erick@gmail.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20250813071837.668613-1-karanja99erick@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-31Merge tag 'mm-stable-2025-05-31-14-50' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of creating a pte which addresses the first page in a folio and reduces the amount of plumbing which architecture must implement to provide this. - "Misc folio patches for 6.16" from Matthew Wilcox is a shower of largely unrelated folio infrastructure changes which clean things up and better prepare us for future work. - "memory,x86,acpi: hotplug memory alignment advisement" from Gregory Price adds early-init code to prevent x86 from leaving physical memory unused when physical address regions are not aligned to memory block size. - "mm/compaction: allow more aggressive proactive compaction" from Michal Clapinski provides some tuning of the (sadly, hard-coded (more sadly, not auto-tuned)) thresholds for our invokation of proactive compaction. In a simple test case, the reduction of a guest VM's memory consumption was dramatic. - "Minor cleanups and improvements to swap freeing code" from Kemeng Shi provides some code cleaups and a small efficiency improvement to this part of our swap handling code. - "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin adds the ability for a ptracer to modify syscalls arguments. At this time we can alter only "system call information that are used by strace system call tampering, namely, syscall number, syscall arguments, and syscall return value. This series should have been incorporated into mm.git's "non-MM" branch, but I goofed. - "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl against /proc/pid/pagemap. This permits CRIU to more efficiently get at the info about guard regions. - "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan implements that fix. No runtime effect is expected because validate_page_before_insert() happens to fix up this error. - "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David Hildenbrand basically brings uprobe text poking into the current decade. Remove a bunch of hand-rolled implementation in favor of using more current facilities. - "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman Khandual provides enhancements and generalizations to the pte dumping code. This might be needed when 128-bit Page Table Descriptors are enabled for ARM. - "Always call constructor for kernel page tables" from Kevin Brodsky ensures that the ctor/dtor is always called for kernel pgtables, as it already is for user pgtables. This permits the addition of more functionality such as "insert hooks to protect page tables". This change does result in various architectures performing unnecesary work, but this is fixed up where it is anticipated to occur. - "Rust support for mm_struct, vm_area_struct, and mmap" from Alice Ryhl adds plumbing to permit Rust access to core MM structures. - "fix incorrectly disallowed anonymous VMA merges" from Lorenzo Stoakes takes advantage of some VMA merging opportunities which we've been missing for 15 years. - "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from SeongJae Park optimizes process_madvise()'s TLB flushing. Instead of flushing each address range in the provided iovec, we batch the flushing across all the iovec entries. The syscall's cost was approximately halved with a microbenchmark which was designed to load this particular operation. - "Track node vacancy to reduce worst case allocation counts" from Sidhartha Kumar makes the maple tree smarter about its node preallocation. stress-ng mmap performance increased by single-digit percentages and the amount of unnecessarily preallocated memory was dramaticelly reduced. - "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes a few unnecessary things which Baoquan noted when reading the code. - ""Enhance sysfs handling for memory hotplug in weighted interleave" from Rakie Kim "enhances the weighted interleave policy in the memory management subsystem by improving sysfs handling, fixing memory leaks, and introducing dynamic sysfs updates for memory hotplug support". Fixes things on error paths which we are unlikely to hit. - "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory" from SeongJae Park introduces new DAMOS quota goal metrics which eliminate the manual tuning which is required when utilizing DAMON for memory tiering. - "mm/vmalloc.c: code cleanup and improvements" from Baoquan He provides cleanups and small efficiency improvements which Baoquan found via code inspection. - "vmscan: enforce mems_effective during demotion" from Gregory Price changes reclaim to respect cpuset.mems_effective during demotion when possible. because presently, reclaim explicitly ignores cpuset.mems_effective when demoting, which may cause the cpuset settings to violated. This is useful for isolating workloads on a multi-tenant system from certain classes of memory more consistently. - "Clean up split_huge_pmd_locked() and remove unnecessary folio pointers" from Gavin Guo provides minor cleanups and efficiency gains in in the huge page splitting and migrating code. - "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache for `struct mem_cgroup', yielding improved memory utilization. - "add max arg to swappiness in memory.reclaim and lru_gen" from Zhongkun He adds a new "max" argument to the "swappiness=" argument for memory.reclaim MGLRU's lru_gen. This directs proactive reclaim to reclaim from only anon folios rather than file-backed folios. - "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the first step on the path to permitting the kernel to maintain existing VMs while replacing the host kernel via file-based kexec. At this time only memblock's reserve_mem is preserved. - "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides and uses a smarter way of looping over a pfn range. By skipping ranges of invalid pfns. - "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning when a task is pinned a single NUMA mode. Dramatic performance benefits were seen in some real world cases. - "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank Garg addresses a warning which occurs during memory compaction when using JFS. - "move all VMA allocation, freeing and duplication logic to mm" from Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more appropriate mm/vma.c. - "mm, swap: clean up swap cache mapping helper" from Kairui Song provides code consolidation and cleanups related to the folio_index() function. - "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that. - "memcg: Fix test_memcg_min/low test failures" from Waiman Long addresses some bogus failures which are being reported by the test_memcontrol selftest. - "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo Stoakes commences the deprecation of file_operations.mmap() in favor of the new file_operations.mmap_prepare(). The latter is more restrictive and prevents drivers from messing with things in ways which, amongst other problems, may defeat VMA merging. - "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples the per-cpu memcg charge cache from the objcg's one. This is a step along the way to making memcg and objcg charging NMI-safe, which is a BPF requirement. - "mm/damon: minor fixups and improvements for code, tests, and documents" from SeongJae Park is yet another batch of miscellaneous DAMON changes. Fix and improve minor problems in code, tests and documents. - "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg stats to be irq safe. Another step along the way to making memcg charging and stats updates NMI-safe, a BPF requirement. - "Let unmap_hugepage_range() and several related functions take folio instead of page" from Fan Ni provides folio conversions in the hugetlb code. * tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits) mm: pcp: increase pcp->free_count threshold to trigger free_high mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range() mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page mm/hugetlb: pass folio instead of page to unmap_ref_private() memcg: objcg stock trylock without irq disabling memcg: no stock lock for cpu hot-unplug memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs memcg: make count_memcg_events re-entrant safe against irqs memcg: make mod_memcg_state re-entrant safe against irqs memcg: move preempt disable to callers of memcg_rstat_updated memcg: memcg_rstat_updated re-entrant safe against irqs mm: khugepaged: decouple SHMEM and file folios' collapse selftests/eventfd: correct test name and improve messages alloc_tag: check mem_profiling_support in alloc_tag_init Docs/damon: update titles and brief introductions to explain DAMOS selftests/damon/_damon_sysfs: read tried regions directories in order mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject() mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat() mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs ...
2025-05-11Documentation: zram: update IDLE pages tracking documentationSergey Senozhatsky
Move IDLE pages tracking into a separate chapter because there are multiple features that use (or depend on) it either in built-in variant ("mark all") or in extended variant (ac-time tracking). In addition, recompression doesn't require memory tracking to be enabled in order to be able to perform idle recompression. Link: https://lkml.kernel.org/r/20250416042833.3858827-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reported-by: Shin Kawamura <kawasin@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11zram: modernize writeback interfaceSergey Senozhatsky
The writeback interface supports a page_index=N parameter which performs writeback of the given page. Since we rarely need to writeback just one single page, the typical use case involves a number of writeback calls, each performing writeback of one page: echo page_index=100 > zram0/writeback ... echo page_index=200 > zram0/writeback echo page_index=500 > zram0/writeback ... echo page_index=700 > zram0/writeback One obvious downside of this is that it increases the number of syscalls. Less obvious, but a significantly more important downside, is that when given only one page to post-process zram cannot perform an optimal target selection. This becomes a critical limitation when writeback_limit is enabled, because under writeback_limit we want to guarantee the highest memory savings hence we first need to writeback pages that release the highest amount of zsmalloc pool memory. This patch adds page_indexes=LOW-HIGH parameter to the writeback interface: echo page_indexes=100-200 page_indexes=500-700 > zram0/writeback This gives zram a chance to apply an optimal target selection strategy on each iteration of the writeback loop. We also now permit multiple page_index parameters per call (previously zram would recognize only one page_index) and a mix or single pages and page ranges: echo page_index=42 page_index=99 page_indexes=100-200 \ page_indexes=500-700 > zram0/writeback Apart from that the patch also unifies parameters passing and resembles other "modern" zram device attributes (e.g. recompression), while the old interface used a mixed scheme: values-less parameters for mode and a key=value format for page_index. We still support the "old" value-less format for compatibility reasons. [senozhatsky@chromium.org: simplify parse_page_index() range checks, per Brian] nk: https://lkml.kernel.org/r/20250404015327.2427684-1-senozhatsky@chromium.org [sozhatsky@chromium.org: fix uninitialized variable in zram_writeback_slots(), per Dan] nk: https://lkml.kernel.org/r/20250409112611.1154282-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20250327015818.4148660-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Richard Chang <richardycc@google.com> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-01Documentation: Document the new zoned loop block device driverDamien Le Moal
Introduce the zoned_loop.rst documentation file under admin-guide/blockdev to document the zoned loop block device driver. An overview of the driver is provided and its usage to create and delete zoned devices described. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20250407075222.170336-3-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-16zram: remove max_comp_streams device attrSergey Senozhatsky
max_comp_streams device attribute has been defunct since May 2016 when zram switched to per-CPU compression streams, remove it. Link: https://lkml.kernel.org/r/20250303022425.285971-5-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Hillf Danton <hdanton@sina.com> Cc: Kairui Song <ryncsn@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Yosry Ahmed <yosry.ahmed@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-12-13Documentation: zram: fix dictionary spellingSaru2003
Fixes a typo in the ZRAM documentation where 'dictioary' was misspelled. Corrected it to 'dictionary' in the example usage of 'algorithm_params'. Signed-off-by: Sarveshwaar SS <sarvesh20123@gmail.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20241125165122.17521-1-sarvesh20123@gmail.com
2024-11-05zram: permit only one post-processing operation at a timeSergey Senozhatsky
Both recompress and writeback soon will unlock slots during processing, which makes things too complex wrt possible race-conditions. We still want to clear PP_SLOT in slot_free, because this is how we figure out that slot that was selected for post-processing has been released under us and when we start post-processing we check if slot still has PP_SLOT set. At the same time, theoretically, we can have something like this: CPU0 CPU1 recompress scan slots set PP_SLOT unlock slot slot_free clear PP_SLOT allocate PP_SLOT writeback scan slots set PP_SLOT unlock slot select PP-slot test PP_SLOT So recompress will not detect that slot has been re-used and re-selected for concurrent writeback post-processing. Make sure that we only permit on post-processing operation at a time. So now recompress and writeback post-processing don't race against each other, we only need to handle slot re-use (slot_free and write), which is handled individually by each pp operation. Having recompress and writeback competing for the same slots is not exactly good anyway (can't imagine anyone doing that). Link: https://lkml.kernel.org/r/20240917021020.883356-3-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09zram: support priority parameter in recompressionSergey Senozhatsky
recompress device attribute supports alg=NAME parameter so that we can specify only one particular algorithm we want to perform recompression with. However, with algo params we now can have several exactly same secondary algorithms but each with its own params tuning (e.g. priority 1 configured to use more aggressive level, and priority 2 configured to use a pre-trained dictionary). Support priority=NUM parameter so that we can correctly determine which secondary algorithm we want to use. Link: https://lkml.kernel.org/r/20240902105656.1383858-25-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09Documentation/zram: add documentation for algorithm parametersSergey Senozhatsky
Document brief description of compression algorithms' parameters: compression level and pre-trained dictionary. [senozhatsky@chromium.org: trivial fixup] Link: https://lkml.kernel.org/r/20240903063722.1603592-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20240902105656.1383858-24-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09zram: introduce algorithm_params device attributeSergey Senozhatsky
This attribute is used to setup compression algorithms' parameters, so we can tweak algorithms' characteristics. At this point only 'level' is supported (to be extended in the future). Each call sets up parameters for one particular algorithm, which should be specified either by the algorithm's priority or algo name. This is expected to be called after corresponding algorithm is selected via comp_algorithm or recomp_algorithm. echo "priority=0 level=1" > /sys/block/zram0/algorithm_params or echo "algo=zstd level=1" > /sys/block/zram0/algorithm_params Link: https://lkml.kernel.org/r/20240902105656.1383858-16-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09zram: introduce custom comp backends APISergey Senozhatsky
Moving to custom backends implementation gives us ability to have our own minimalistic and extendable API, and algorithms tunings becomes possible. The list of compression backends is empty at this point, we will add backends in the followup patches. Link: https://lkml.kernel.org/r/20240902105656.1383858-5-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25zram: add max_pages param to recompressionSergey Senozhatsky
Introduce "max_pages" param to recompress device attribute which sets an upper limit on the number of entries (pages) zram attempts to recompress (in this particular recompression call). S/W recompression can be quite expensive so limiting the number of pages recompress touches can be quite helpful. Link: https://lkml.kernel.org/r/20240329094050.2815699-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10zram: split memory-tracking and ac-time trackingSergey Senozhatsky
ZRAM_MEMORY_TRACKING enables two features: - per-entry ac-time tracking - debugfs interface The latter one is the reason why memory-tracking depends on DEBUG_FS, while the former one is used far beyond debugging these days. Namely ac-time is used for fine grained writeback of idle entries (pages). Move ac-time tracking under its own config option so that it can be enabled (along with writeback) on systems without DEBUG_FS. [senozhatsky@chromium.org: ifdef fixup, per Dmytro] Link: https://lkml.kernel.org/r/20231117013543.540280-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20231115024223.4133148-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dmytro Maluka <dmaluka@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-27docs nbd: userspace NBD now favors github over sourceforgeEric Blake
While the sourceforge site for userspace NBD still exists, the code repository moved to github several years ago. Then with a recent patch[1], the github landing page contains just as much information as the sourceforge page, so we might as well point to a single location that also provides the code. [1] https://lists.debian.org/nbd/2023/03/msg00051.html Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Link: https://lore.kernel.org/r/20230410180611.1051618-5-eblake@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-01-31drivers/block: Remove PARIDE core and high-level protocolsOndrej Zary
Remove PARIDE core and high level protocols, taking care not to break low-level drivers (used by pata_parport). Also update documentation. Signed-off-by: Ondrej Zary <linux@zary.sk> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
2023-01-31ata: pata_parport: add driver (PARIDE replacement)Ondrej Zary
The pata_parport is a libata-based replacement of the old PARIDE subsystem - driver for parallel port IDE devices. It uses the original paride low-level protocol drivers but does not need the high-level drivers (pd, pcd, pf, pt, pg). The IDE devices behind parallel port adapters are handled by the ATA layer. This will allow paride and its high-level drivers to be removed. Unfortunately, libata drivers cannot sleep so pata_parport claims parport before activating the ata host and keeps it claimed (and protocol connected) until the ata host is removed. This means that no devices can be chained (neither other pata_parport devices nor a printer). paride and pata_parport are mutually exclusive because the compiled protocol drivers are incompatible. Tested with: - Imation SuperDisk LS-120 and HP C4381A (EPAT) - Freecom Parallel CD (FRPW) - Toshiba Mobile CD-RW 2793008 w/Freecom Parallel Cable rev.903 (FRIQ) - Backpack CD-RW 222011 and CD-RW 19350 (BPCK6) The following bugs in low-level protocol drivers were found and will be fixed later: Note: EPP-32 mode is buggy in EPAT - and also in all other protocol drivers - they don't handle non-multiple-of-4 block transfers correctly. This causes problems with LS-120 drive. There is also another bug in EPAT: EPP modes don't work unless a 4-bit or 8-bit mode is used first (probably some initialization missing?). Once the device is initialized, EPP works until power cycle. So after device power on, you have to: echo "parport0 epat 0" >/sys/bus/pata_parport/new_device echo pata_parport.0 >/sys/bus/pata_parport/delete_device echo "parport0 epat 4" >/sys/bus/pata_parport/new_device (autoprobe will initialize correctly as it tries the slowest modes first but you'll get the broken EPP-32 mode) Note: EPP modes are buggy in FRPW, only modes 0 and 1 work. Signed-off-by: Ondrej Zary <linux@zary.sk> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
2022-11-30zram: add incompressible flag to read_block_state()Sergey Senozhatsky
Add a new flag to zram block state that shows if the page is incompressible: that none of the algorithm (including secondary ones) could compress it. Link: https://lkml.kernel.org/r/20221109115047.2921851-14-senozhatsky@chromium.org Suggested-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Alexey Romanov <avromanov@sberdevices.ru> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30zram: add incompressible writebackSergey Senozhatsky
Add support for incompressible pages writeback: echo incompressible > /sys/block/zramX/writeback Link: https://lkml.kernel.org/r/20221109115047.2921851-13-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Alexey Romanov <avromanov@sberdevices.ru> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30documentation: add zram recompression documentationSergey Senozhatsky
Document user-space visible device attributes that are enabled by ZRAM_MULTI_COMP. Link: https://lkml.kernel.org/r/20221109115047.2921851-12-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Alexey Romanov <avromanov@sberdevices.ru> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30zram: add recompress flag to read_block_state()Sergey Senozhatsky
Add a new flag to zram block state that shows if the page was recompressed (using alternative compression algorithm). Link: https://lkml.kernel.org/r/20221109115047.2921851-6-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Alexey Romanov <avromanov@sberdevices.ru> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-06-02Merge tag 'docs-5.19-2' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation fixes from Jonathan Corbet: "A handful of late-arriving documentation fixes and the addition of an SVG tux logo which, I'm assured, we're going to want" * tag 'docs-5.19-2' of git://git.lwn.net/linux: documentation: Format button_dev as a pointer. docs: add SVG version of the Linux logo docs: move Linux logo into a new `images` folder docs: blockdev: change title to match section content docs/conf.py: Cope with removal of language=None in Sphinx 5.0.0
2022-06-01docs: blockdev: change title to match section contentJoel Colledge
This index.rst was added in commit 39443104c7d3 docs: blockdev: convert to ReST It appears that the title from the RapidIO index page was copied. This title does not match the content of this directory. Change it to match. Signed-off-by: Joel Colledge <joel.colledge@linbit.com> Link: https://lore.kernel.org/r/20220530142849.717-1-joel.colledge@linbit.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-04-29zram: add a huge_idle writeback modeBrian Geffon
Today it's only possible to write back as a page, idle, or huge. A user might want to writeback pages which are huge and idle first as these idle pages do not require decompression and make a good first pass for writeback. Idle writeback specifically has the advantage that a refault is unlikely given that the page has been swapped for some amount of time without being refaulted. Huge writeback has the advantage that you're guaranteed to get the maximum benefit from a single page writeback, that is, you're reclaiming one full page of memory. Pages which are compressed in zram being written back result in some benefit which is always less than a page size because of the fact that it was compressed. The primary use of this is for minimizing refaults in situations where the device has to be sensitive to storage endurance. On ChromeOS we have devices with slow eMMC and repeated writes and refaults can negatively affect performance and endurance. Link: https://lkml.kernel.org/r/20220322215821.1196994-1-bgeffon@google.com Signed-off-by: Brian Geffon <bgeffon@google.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-02-15docs: Fix wording in optional zram feature docsEthan Dye
This fixes some simple grammar errors in the documentation for zram, specifically errors in the optional feature section of the zram documentation. Signed-off-by: Ethan Dye <mrtops03@gmail.com> Link: https://lore.kernel.org/r/20220207235442.95090-1-mrtops03@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-29docs: admin-guide/blockdev: Remove digraph of node-statesAkira Yokosawa
While node-states-8.dot has two digraphs, the dot(1) command can not properly handle multiple graphs in a DOT file and the kernel-doc page at https://www.kernel.org/doc/html/latest/admin-guide/blockdev/drbd/figures.html fails to render the graphs. It turned out that the digraph of node_states can be removed. Quote from Joel's reflection: On reflection, the digraph node_states can be removed entirely. It is too basic to contain any useful information. In addition it references "ioctl_set_state". The ioctl configuration interface for DRBD has long been removed. In fact, it was never in the upstream version of DRBD. Remove node_states and rename the DOT file peer_states-8.dot. Suggested-by: Joel Colledge <joel.colledge@linbit.com> Acked-by: Joel Colledge <joel.colledge@linbit.com> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: Lars Ellenberg <lars.ellenberg@linbit.com> Link: https://lore.kernel.org/r/7df04f45-8746-e666-1a9d-a998f1ab1f91@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-06zram: introduce an aged idle interfaceBrian Geffon
This change introduces an aged idle interface to the existing idle sysfs file for zram. When CONFIG_ZRAM_MEMORY_TRACKING is enabled the idle file now also accepts an integer argument. This integer is the age (in seconds) of pages to mark as idle. The idle file still supports 'all' as it always has. This new approach allows for much more control over which pages get marked as idle. [bgeffon@google.com: use IS_ENABLED and cleanup comment] Link: https://lkml.kernel.org/r/20210924161128.1508015-1-bgeffon@google.com [bgeffon@google.com: Sergey's cleanup suggestions] Link: https://lkml.kernel.org/r/20210929143056.13067-1-bgeffon@google.com Link: https://lkml.kernel.org/r/20210923130115.1344361-1-bgeffon@google.com Signed-off-by: Brian Geffon <bgeffon@google.com> Acked-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Jesse Barnes <jsbarnes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc updates from Andrew Morton: - a few random little subsystems - almost all of the MM patches which are staged ahead of linux-next material. I'll trickle to post-linux-next work in as the dependents get merged up. Subsystems affected by this patch series: kthread, kbuild, ide, ntfs, ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation, kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction, oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc, uaccess, zram, and cleanups). * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits) mm: cleanup kstrto*() usage mm: fix fall-through warnings for Clang mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at mm: shmem: convert shmem_enabled_show to use sysfs_emit_at mm:backing-dev: use sysfs_emit in macro defining functions mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening mm: use sysfs_emit for struct kobject * uses mm: fix kernel-doc markups zram: break the strict dependency from lzo zram: add stat to gather incompressible pages since zram set up zram: support page writeback mm/process_vm_access: remove redundant initialization of iov_r mm/zsmalloc.c: rework the list_add code in insert_zspage() mm/zswap: move to use crypto_acomp API for hardware acceleration mm/zswap: fix passing zero to 'PTR_ERR' warning mm/zswap: make struct kernel_param_ops definitions const userfaultfd/selftests: hint the test runner on required privilege userfaultfd/selftests: fix retval check for userfaultfd_open() userfaultfd/selftests: always dump something in modes userfaultfd: selftests: make __{s,u}64 format specifiers portable ...
2020-12-15zram: add stat to gather incompressible pages since zram set upMinchan Kim
Currently, zram supports the stat via /sys/block/zram/mm_stat to represent how many of incompressible pages are stored at the moment but it couldn't show how many times incompressible pages were wrote down since zram set up. It's also good indication to see how zram is effective in the system. Link: https://lkml.kernel.org/r/20201130201907.1284910-1-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15zram: support page writebackMinchan Kim
There is demand to writeback specific process pages to backing store instead of all idles pages in the system due to storage wear out concerns and to launching latency of apps which are most of the time idle but are critical for resume latency. This patch extends the writeback knob to support a specific page writeback. Link: https://lkml.kernel.org/r/20201020190506.3758660-1-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-08Documentation: fix typos found in admin-guide subdirectoryAndrew Klychkov
Fixed twelve typos in cppc_sysfs.rst, binderfs.rst, paride.rst, zram.rst, bug-hunting.rst, introduction.rst, usage.rst, dm-crypt.rst Signed-off-by: Andrew Klychkov <andrew.a.klychkov@gmail.com> Reviewed-by: Jonathan Corbet <corbet@lwn.net> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20201204070235.GA48631@spblnx124.lan Signed-off-by: Jonathan Corbet <corbet@lwn.net>