kernel/linux.git/include/linux/sched, branch v6.18.21

mm: describe @flags parameter in memalloc_flags_save()

2026-01-23T10:21:20+00:00

[ Upstream commit e2fb7836b01747815f8bb94981c35f2688afb120 ] Patch series "mm kernel-doc fixes". Here are kernel-doc fixes for mm subsystem. I'm also including textsearch fix since there's currently no maintainer for include/linux/textsearch.h (get_maintainer.pl only shows LKML). This patch (of 4): Sphinx reports kernel-doc warning: WARNING: ./include/linux/sched/mm.h:332 function parameter 'flags' not described in 'memalloc_flags_save' Describe @flags to fix it. Link: https://lkml.kernel.org/r/20251219014006.16328-2-bagasdotme@gmail.com Link: https://lkml.kernel.org/r/20251219014006.16328-3-bagasdotme@gmail.com Signed-off-by: Bagas Sanjaya Fixes: 3f6d5e6a468d ("mm: introduce memalloc_flags_{save,restore}") Acked-by: David Hildenbrand (Red Hat) Acked-by: Harry Yoo Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

sched/fair: Proportional newidle balance

2026-01-11T14:26:19+00:00

commit 33cf66d88306663d16e4759e9d24766b0aaa2e17 upstream. Add a randomized algorithm that runs newidle balancing proportional to its success rate. This improves schbench significantly: 6.18-rc4: 2.22 Mrps/s 6.18-rc4+revert: 2.04 Mrps/s 6.18-rc4+revert+random: 2.18 Mrps/S Conversely, per Adam Li this affects SpecJBB slightly, reducing it by 1%: 6.17: -6% 6.17+revert: 0% 6.17+revert+random: -1% Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Dietmar Eggemann Tested-by: Dietmar Eggemann Tested-by: Chris Mason Link: https://lkml.kernel.org/r/6825c50d-7fa7-45d8-9b81-c6e7e25738e2@meta.com Link: https://patch.msgid.link/20251107161739.770122091@infradead.org Signed-off-by: Greg Kroah-Hartman

Merge tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-10-03T01:44:54+00:00

Pull non-MM updates from Andrew Morton: - "ida: Remove the ida_simple_xxx() API" from Christophe Jaillet completes the removal of this legacy IDR API - "panic: introduce panic status function family" from Jinchao Wang provides a number of cleanups to the panic code and its various helpers, which were rather ad-hoc and scattered all over the place - "tools/delaytop: implement real-time keyboard interaction support" from Fan Yu adds a few nice user-facing usability changes to the delaytop monitoring tool - "efi: Fix EFI boot with kexec handover (KHO)" from Evangelos Petrongonas fixes a panic which was happening with the combination of EFI and KHO - "Squashfs: performance improvement and a sanity check" from Phillip Lougher teaches squashfs's lseek() about SEEK_DATA/SEEK_HOLE. A mere 150x speedup was measured for a well-chosen microbenchmark - plus another 50-odd singleton patches all over the place * tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (75 commits) Squashfs: reject negative file sizes in squashfs_read_inode() kallsyms: use kmalloc_array() instead of kmalloc() MAINTAINERS: update Sibi Sankar's email address Squashfs: add SEEK_DATA/SEEK_HOLE support Squashfs: add additional inode sanity checking lib/genalloc: fix device leak in of_gen_pool_get() panic: remove CONFIG_PANIC_ON_OOPS_VALUE ocfs2: fix double free in user_cluster_connect() checkpatch: suppress strscpy warnings for userspace tools cramfs: fix incorrect physical page address calculation kernel: prevent prctl(PR_SET_PDEATHSIG) from racing with parent process exit Squashfs: fix uninit-value in squashfs_get_parent kho: only fill kimage if KHO is finalized ocfs2: avoid extra calls to strlen() after ocfs2_sprintf_system_inode_name() kernel/sys.c: fix the racy usage of task_lock(tsk->group_leader) in sys_prlimit64() paths sched/task.h: fix the wrong comment on task_lock() nesting with tasklist_lock coccinelle: platform_no_drv_owner: handle also built-in drivers coccinelle: of_table: handle SPI device ID tables lib/decompress: use designated initializers for struct compress_format efi: support booting with kexec handover (KHO) ...

Merge tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-10-03T01:18:33+00:00

Pull MM updates from Andrew Morton: - "mm, swap: improve cluster scan strategy" from Kairui Song improves performance and reduces the failure rate of swap cluster allocation - "support large align and nid in Rust allocators" from Vitaly Wool permits Rust allocators to set NUMA node and large alignment when perforning slub and vmalloc reallocs - "mm/damon/vaddr: support stat-purpose DAMOS" from Yueyang Pan extend DAMOS_STAT's handling of the DAMON operations sets for virtual address spaces for ops-level DAMOS filters - "execute PROCMAP_QUERY ioctl under per-vma lock" from Suren Baghdasaryan reduces mmap_lock contention during reads of /proc/pid/maps - "mm/mincore: minor clean up for swap cache checking" from Kairui Song performs some cleanup in the swap code - "mm: vm_normal_page*() improvements" from David Hildenbrand provides code cleanup in the pagemap code - "add persistent huge zero folio support" from Pankaj Raghav provides a block layer speedup by optionalls making the huge_zero_pagepersistent, instead of releasing it when its refcount falls to zero - "kho: fixes and cleanups" from Mike Rapoport adds a few touchups to the recently added Kexec Handover feature - "mm: make mm->flags a bitmap and 64-bit on all arches" from Lorenzo Stoakes turns mm_struct.flags into a bitmap. To end the constant struggle with space shortage on 32-bit conflicting with 64-bit's needs - "mm/swapfile.c and swap.h cleanup" from Chris Li cleans up some swap code - "selftests/mm: Fix false positives and skip unsupported tests" from Donet Tom fixes a few things in our selftests code - "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised" from David Hildenbrand "allows individual processes to opt-out of THP=always into THP=madvise, without affecting other workloads on the system". It's a long story - the [1/N] changelog spells out the considerations - "Add and use memdesc_flags_t" from Matthew Wilcox gets us started on the memdesc project. Please see https://kernelnewbies.org/MatthewWilcox/Memdescs and https://blogs.oracle.com/linux/post/introducing-memdesc - "Tiny optimization for large read operations" from Chi Zhiling improves the efficiency of the pagecache read path - "Better split_huge_page_test result check" from Zi Yan improves our folio splitting selftest code - "test that rmap behaves as expected" from Wei Yang adds some rmap selftests - "remove write_cache_pages()" from Christoph Hellwig removes that function and converts its two remaining callers - "selftests/mm: uffd-stress fixes" from Dev Jain fixes some UFFD selftests issues - "introduce kernel file mapped folios" from Boris Burkov introduces the concept of "kernel file pages". Using these permits btrfs to account its metadata pages to the root cgroup, rather than to the cgroups of random inappropriate tasks - "mm/pageblock: improve readability of some pageblock handling" from Wei Yang provides some readability improvements to the page allocator code - "mm/damon: support ARM32 with LPAE" from SeongJae Park teaches DAMON to understand arm32 highmem - "tools: testing: Use existing atomic.h for vma/maple tests" from Brendan Jackman performs some code cleanups and deduplication under tools/testing/ - "maple_tree: Fix testing for 32bit compiles" from Liam Howlett fixes a couple of 32-bit issues in tools/testing/radix-tree.c - "kasan: unify kasan_enabled() and remove arch-specific implementations" from Sabyrzhan Tasbolatov moves KASAN arch-specific initialization code into a common arch-neutral implementation - "mm: remove zpool" from Johannes Weiner removes zspool - an indirection layer which now only redirects to a single thing (zsmalloc) - "mm: task_stack: Stack handling cleanups" from Pasha Tatashin makes a couple of cleanups in the fork code - "mm: remove nth_page()" from David Hildenbrand makes rather a lot of adjustments at various nth_page() callsites, eventually permitting the removal of that undesirable helper function - "introduce kasan.write_only option in hw-tags" from Yeoreum Yun creates a KASAN read-only mode for ARM, using that architecture's memory tagging feature. It is felt that a read-only mode KASAN is suitable for use in production systems rather than debug-only - "mm: hugetlb: cleanup hugetlb folio allocation" from Kefeng Wang does some tidying in the hugetlb folio allocation code - "mm: establish const-correctness for pointer parameters" from Max Kellermann makes quite a number of the MM API functions more accurate about the constness of their arguments. This was getting in the way of subsystems (in this case CEPH) when they attempt to improving their own const/non-const accuracy - "Cleanup free_pages() misuse" from Vishal Moola fixes a number of code sites which were confused over when to use free_pages() vs __free_pages() - "Add Rust abstraction for Maple Trees" from Alice Ryhl makes the mapletree code accessible to Rust. Required by nouveau and by its forthcoming successor: the new Rust Nova driver - "selftests/mm: split_huge_page_test: split_pte_mapped_thp improvements" from David Hildenbrand adds a fix and some cleanups to the thp selftesting code - "mm, swap: introduce swap table as swap cache (phase I)" from Chris Li and Kairui Song is the first step along the path to implementing "swap tables" - a new approach to swap allocation and state tracking which is expected to yield speed and space improvements. This patchset itself yields a 5-20% performance benefit in some situations - "Some ptdesc cleanups" from Matthew Wilcox utilizes the new memdesc layer to clean up the ptdesc code a little - "Fix va_high_addr_switch.sh test failure" from Chunyu Hu fixes some issues in our 5-level pagetable selftesting code - "Minor fixes for memory allocation profiling" from Suren Baghdasaryan addresses a couple of minor issues in relatively new memory allocation profiling feature - "Small cleanups" from Matthew Wilcox has a few cleanups in preparation for more memdesc work - "mm/damon: add addr_unit for DAMON_LRU_SORT and DAMON_RECLAIM" from Quanmin Yan makes some changes to DAMON in furtherance of supporting arm highmem - "selftests/mm: Add -Wunreachable-code and fix warnings" from Muhammad Anjum adds that compiler check to selftests code and fixes the fallout, by removing dead code - "Improvements to Victim Process Thawing and OOM Reaper Traversal Order" from zhongjinji makes a number of improvements in the OOM killer: mainly thawing a more appropriate group of victim threads so they can release resources - "mm/damon: misc fixups and improvements for 6.18" from SeongJae Park is a bunch of small and unrelated fixups for DAMON - "mm/damon: define and use DAMON initialization check function" from SeongJae Park implement reliability and maintainability improvements to a recently-added bug fix - "mm/damon/stat: expose auto-tuned intervals and non-idle ages" from SeongJae Park provides additional transparency to userspace clients of the DAMON_STAT information - "Expand scope of khugepaged anonymous collapse" from Dev Jain removes some constraints on khubepaged's collapsing of anon VMAs. It also increases the success rate of MADV_COLLAPSE against an anon vma - "mm: do not assume file == vma->vm_file in compat_vma_mmap_prepare()" from Lorenzo Stoakes moves us further towards removal of file_operations.mmap(). This patchset concentrates upon clearing up the treatment of stacked filesystems - "mm: Improve mlock tracking for large folios" from Kiryl Shutsemau provides some fixes and improvements to mlock's tracking of large folios. /proc/meminfo's "Mlocked" field became more accurate - "mm/ksm: Fix incorrect accounting of KSM counters during fork" from Donet Tom fixes several user-visible KSM stats inaccuracies across forks and adds selftest code to verify these counters - "mm_slot: fix the usage of mm_slot_entry" from Wei Yang addresses some potential but presently benign issues in KSM's mm_slot handling * tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (372 commits) mm: swap: check for stable address space before operating on the VMA mm: convert folio_page() back to a macro mm/khugepaged: use start_addr/addr for improved readability hugetlbfs: skip VMAs without shareable locks in hugetlb_vmdelete_list alloc_tag: fix boot failure due to NULL pointer dereference mm: silence data-race in update_hiwater_rss mm/memory-failure: don't select MEMORY_ISOLATION mm/khugepaged: remove definition of struct khugepaged_mm_slot mm/ksm: get mm_slot by mm_slot_entry() when slot is !NULL hugetlb: increase number of reserving hugepages via cmdline selftests/mm: add fork inheritance test for ksm_merging_pages counter mm/ksm: fix incorrect KSM counter handling in mm_struct during fork drivers/base/node: fix double free in register_one_node() mm: remove PMD alignment constraint in execmem_vmalloc() mm/memory_hotplug: fix typo 'esecially' -> 'especially' mm/rmap: improve mlock tracking for large folios mm/filemap: map entire large folio faultaround mm/fault: try to map the entire file folio in finish_fault() mm/rmap: mlock large folios in try_to_unmap_one() mm/rmap: fix a mlock race condition in folio_referenced_one() ...

Merge tag 'sched-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-09-30T17:35:11+00:00

Pull scheduler updates from Ingo Molnar: "Core scheduler changes: - Make migrate_{en,dis}able() inline, to improve performance (Menglong Dong) - Move STDL_INIT() functions out-of-line (Peter Zijlstra) - Unify the SCHED_{SMT,CLUSTER,MC} Kconfig (Peter Zijlstra) Fair scheduling: - Defer throttling to when tasks exit to user-space, to reduce the chance & impact of throttle-preemption with held locks and other resources (Aaron Lu, Valentin Schneider) - Get rid of sched_domains_curr_level hack for tl->cpumask(), as the warning was getting triggered on certain topologies (Peter Zijlstra) Misc cleanups & fixes: - Header cleanups (Menglong Dong) - Fix race in push_dl_task() (Harshit Agarwal)" * tag 'sched-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix some typos in include/linux/preempt.h sched: Make migrate_{en,dis}able() inline rcu: Replace preempt.h with sched.h in include/linux/rcupdate.h arch: Add the macro COMPILE_OFFSETS to all the asm-offsets.c sched/fair: Do not balance task to a throttled cfs_rq sched/fair: Do not special case tasks in throttled hierarchy sched/fair: update_cfs_group() for throttled cfs_rqs sched/fair: Propagate load for throttled cfs_rq sched/fair: Get rid of throttled_lb_pair() sched/fair: Task based throttle time accounting sched/fair: Switch to task based throttle model sched/fair: Implement throttle task work and related helpers sched/fair: Add related data structure for task based throttle sched: Unify the SCHED_{SMT,CLUSTER,MC} Kconfig sched: Move STDL_INIT() functions out-of-line sched/fair: Get rid of sched_domains_curr_level hack for tl->cpumask() sched/deadline: Fix race in push_dl_task()

Merge tag 'cgroup-for-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

2025-09-30T16:55:41+00:00

Pull cgroup updates from Tejun Heo: - Extensive cpuset code cleanup and refactoring work with no functional changes: CPU mask computation logic refactoring, introducing new helpers, removing redundant code paths, and improving error handling for better maintainability. - A few bug fixes to cpuset including fixes for partition creation failures when isolcpus is in use, missing error returns, and null pointer access prevention in free_tmpmasks(). - Core cgroup changes include replacing the global percpu_rwsem with per-threadgroup rwsem when writing to cgroup.procs for better scalability, workqueue conversions to use WQ_PERCPU and system_percpu_wq to prepare for workqueue default switching from percpu to unbound, and removal of unused code including the post_attach callback. - New cgroup.stat.local time accounting feature that tracks frozen time duration. - Misc changes including selftests updates (new freezer time tests and backward compatibility fixes), documentation sync, string function safety improvements, and 64-bit division fixes. * tag 'cgroup-for-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (39 commits) cpuset: remove is_prs_invalid helper cpuset: remove impossible warning in update_parent_effective_cpumask cpuset: remove redundant special case for null input in node mask update cpuset: fix missing error return in update_cpumask cpuset: Use new excpus for nocpu error check when enabling root partition cpuset: fix failure to enable isolated partition when containing isolcpus Documentation: cgroup-v2: Sync manual toctree cpuset: use partition_cpus_change for setting exclusive cpus cpuset: use parse_cpulist for setting cpus.exclusive cpuset: introduce partition_cpus_change cpuset: refactor cpus_allowed_validate_change cpuset: refactor out validate_partition cpuset: introduce cpus_excl_conflict and mems_excl_conflict helpers cpuset: refactor CPU mask buffer parsing logic cpuset: Refactor exclusive CPU mask computation logic cpuset: change return type of is_partition_[in]valid to bool cpuset: remove unused assignment to trialcs->partition_root_state cpuset: move the root cpuset write check earlier cgroup/cpuset: Remove redundant rcu_read_lock/unlock() in spin_lock cgroup: Remove redundant rcu_read_lock/unlock() in spin_lock ...

Merge tag 'sched_ext-for-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

2025-09-30T16:05:07+00:00

Pull sched_ext updates from Tejun Heo: - Code organization cleanup. Separate internal types and accessors to ext_internal.h to reduce the size of ext.c and improve maintainability. - Prepare for cgroup sub-scheduler support by adding @sch parameter to various functions and helpers, reorganizing scheduler instance handling, and dropping obsolete helpers like scx_kf_exit() and kf_cpu_valid(). - Add new scx_bpf_cpu_curr() and scx_bpf_locked_rq() BPF helpers to provide safer access patterns with proper RCU protection. scx_bpf_cpu_rq() is deprecated with warnings due to potential race conditions. - Improve debugging with migration-disabled counter in error state dumps, SCX_EFLAG_INITIALIZED flag, bitfields for warning flags, and other enhancements to help diagnose issues. - Use cgroup_lock/unlock() for cgroup synchronization instead of scx_cgroup_rwsem based synchronization. This is simpler and allows enable/disable paths to synchronize against cgroup changes independent of the CPU controller. - rhashtable_lookup() replacement to avoid redundant RCU locking was reverted due to RCU usage warnings. Will be redone once rhashtable is updated to use rcu_dereference_all(). - Other misc updates and fixes including bypass handling improvements, scx_task_iter_relock() improvements, tools/sched_ext updates, and compatibility helpers. * tag 'sched_ext-for-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: (28 commits) Revert "sched_ext: Use rhashtable_lookup() instead of rhashtable_lookup_fast()" sched_ext: Misc updates around scx_sched instance pointer sched_ext: Drop scx_kf_exit() and scx_kf_error() sched_ext: Add the @sch parameter to scx_dsq_insert_preamble/commit() sched_ext: Drop kf_cpu_valid() sched_ext: Add the @sch parameter to ext_idle helpers sched_ext: Add the @sch parameter to __bstr_format() sched_ext: Separate out scx_kick_cpu() and add @sch to it tools/sched_ext: scx_qmap: Make debug output quieter by default sched_ext: Make qmap dump operation non-destructive sched_ext: Add SCX_EFLAG_INITIALIZED to indicate successful ops.init() sched_ext: Use bitfields for boolean warning flags sched_ext: Fix stray scx_root usage in task_can_run_on_remote_rq() sched_ext: Improve SCX_KF_DISPATCH comment sched_ext: Use rhashtable_lookup() instead of rhashtable_lookup_fast() sched_ext: Verify RCU protection in scx_bpf_cpu_curr() sched_ext: Add migration-disabled counter to error state dump sched_ext: Fix NULL dereference in scx_bpf_cpu_rq() warning tools/sched_ext: Add compat helper for scx_bpf_cpu_curr() sched_ext: deprecation warn for scx_bpf_cpu_rq() ...

sched_ext: Improve SCX_KF_DISPATCH comment

2025-09-23T19:03:26+00:00

The comment for SCX_KF_DISPATCH was incomplete and didn't explain that ops.dispatch() may temporarily release the rq lock, allowing ENQUEUE and SELECT_CPU operations to be nested inside DISPATCH contexts. Update the comment to clarify this nesting behavior and provide better context for when these operations can occur within dispatch. Acked-by: Andrea Righi Signed-off-by: Tejun Heo

sched/task.h: fix the wrong comment on task_lock() nesting with tasklist_lock

2025-09-23T03:10:59+00:00

The ancient comment above task_lock() states that it can be nested outside of read_lock(&tasklist_lock), but this is no longer true: CPU_0 CPU_1 CPU_2 task_lock() read_lock(tasklist) write_lock_irq(tasklist) read_lock(tasklist) task_lock() Unless CPU_0 calls read_lock() in IRQ context, queued_read_lock_slowpath() won't get the lock immediately, it will spin waiting for the pending writer on CPU_2, resulting in a deadlock. Link: https://lkml.kernel.org/r/20250914110908.GA18769@redhat.com Signed-off-by: Oleg Nesterov Cc: Christian Brauner Cc: Jiri Slaby Cc: Mateusz Guzik Signed-off-by: Andrew Morton

mm: constify arch_pick_mmap_layout() for improved const-correctness

2025-09-21T21:22:14+00:00

This function only reads from the rlimit pointer (but writes to the mm_struct pointer which is kept without `const`). All callees are already const-ified or (internal functions) are being constified by this patch. Link: https://lkml.kernel.org/r/20250901205021.3573313-9-max.kellermann@ionos.com Signed-off-by: Max Kellermann Reviewed-by: Vishal Moola (Oracle) Reviewed-by: Lorenzo Stoakes Acked-by: David Hildenbrand Acked-by: Vlastimil Babka Acked-by: Mike Rapoport (Microsoft) Acked-by: Shakeel Butt Cc: Alexander Gordeev Cc: Al Viro Cc: Andreas Larsson Cc: Andy Lutomirski Cc: Axel Rasmussen Cc: Baolin Wang Cc: Borislav Betkov Cc: Christian Borntraeger Cc: Christian Brauner Cc: Christian Zankel Cc: David Rientjes Cc: David S. Miller Cc: Gerald Schaefer Cc: Heiko Carstens Cc: Helge Deller Cc: "H. Peter Anvin" Cc: Hugh Dickins Cc: Ingo Molnar Cc: James Bottomley Cc: Jan Kara Cc: Jocelyn Falempe Cc: Liam Howlett Cc: Mark Brown Cc: Matthew Wilcox (Oracle) Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Hocko Cc: "Nysal Jan K.A" Cc: Oscar Salvador Cc: Peter Zijlstra Cc: Russel King Cc: Suren Baghdasaryan Cc: Sven Schnelle Cc: Thomas Gleinxer Cc: Thomas Huth Cc: Vasily Gorbik Cc: Wei Xu Cc: Yuanchu Xie Signed-off-by: Andrew Morton