kernel/git/next/linux-next.git/arch/riscv/Kconfig, branch master

Merge branch 'master' of ssh://git@gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip.git

2026-09-21T12:14:15+00:00

Merge branch into tip/master: 'sched/core'

2026-09-21T08:46:10+00:00

# New commits in sched/core: e81ee0630837 ("sched/fair: Reset NUMA fault locality after scan period update") ef9293b3b797 ("sched: dynamic: Fix preemption model strings") 879eaa76e608 ("sched: Remove unneeded function type cast in do_balance_callbacks()") f549101187c8 ("sched/deadline: check start_dl_timer expiry with ktime_before()") 2a672daa4b27 ("sched/feat: Use the new static key API for sched_feat") a5576ebce920 ("sched: Convert paravirt_steal to new static key APIs") 9650ce11f2e3 ("sched: dynamic: Simplify preempt model accessors") 5b9a28eeed37 ("sched: dynamic: Remove HAVE_PREEMPT_DYNAMIC_{CALL,KEY}") aa4178f63847 ("sched: dynamic: Simplify irqentry_exit_cond_resched()") b9d267b9d632 ("sched: dynamic: Simplify preempt_schedule{,_notrace}()") 88e0b3bb9930 ("sched: dynamic: Simplify {cond,might}_resched()") d3d16750693b ("sched: dynamic: Make PREEMPT_DYNAMIC depend on ARCH_HAS_PREEMPT_LAZY") 772d9ffbfd26 ("sched: Migrate whole chain in proxy_migrate_task()") 6b73a09e943f ("sched: Break out core of attach_tasks() helper into sched.h") 1f8805138593 ("sched: Switch rq->next_class in proxy_reset_donor()") 09351db90a28 ("sched/core: Don't proxy-exec unmatched cookie lock owners") 9be817f991e2 ("sched/core: Avoid migrating blocked_on tasks") 3dd95f077371 ("sched/core: Don't steal a proxy-exec donor") Signed-off-by: Ingo Molnar

Merge https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable into for-next

2026-09-21T07:08:39+00:00

Signed-off-by: David Hildenbrand (Arm) # Conflicts: # drivers/infiniband/hw/hfi1/file_ops.c # Conflict resolution: # # diff --git a/drivers/infiniband/hw/hfi1/file_ops.c b/drivers/infiniband/hw/hfi1/file_ops.c # index d495b99f6514..680364fda856 100644 # --- a/drivers/infiniband/hw/hfi1/file_ops.c # +++ b/drivers/infiniband/hw/hfi1/file_ops.c # @@ -320,12 +320,8 @@ static int hfi1_file_mmap(struct file *fp, struct vm_area_struct *vma) # memaddr = 0; # void *memvirt = NULL; # dma_addr_t memdma = 0; # -<<<<<<< HEAD # - u8 subctxt, mapio = 0, vmf = 0, type; # - size_t memdmalen = 0; # -======= # u8 subctxt, mapio = 0, is_vmalloc = 0, type; # ->>>>>>> akpm/mm-unstable # + size_t memdmalen = 0; # ssize_t memlen = 0; # int ret = 0; # u16 ctxt;

mm: make userland page table freeing RCU-safe

2026-09-20T16:19:42+00:00

Now every architecture has been converted to support CONFIG_MMU_GATHER_RCU_TABLE_FREE, this configuration option no longer makes any sense to keep around. Therefore remove it, and remove all the dead code that existed for !CONFIG_MMU_GATHER_RCU_TABLE_FREE architectures previously. Additionally, CONFIG_MMU_GATHER_TABLE_FREE is no longer necessary, as all architectures instead use CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE when a custom __tlb_remove_table() is required, so remove this too. A number of architectures only enabled CONFIG_MMU_GATHER_RCU_TABLE_FREE if CONFIG_MMU was set, however the mmu_gather logic only actually does something meaningful if CONFIG_MMU is set (mmu_gather.c is only compiled in this case, for instance). As a result, there's no need to gate any of this logic on CONFIG_MMU explicitly. CONFIG_PT_RECLAIM however does have a strict dependency on CONFIG_MMU, so make this dependency explicit. Additionally, correct comments to remove references to non-RCU page table gathering and make it clear that this is not 'semi-RCU', nor has it been since commit 1fb3d8c20bfa ("mm/mmu_gather: replace IPI with synchronize_rcu() when batch allocation fails"). With this change in place the kernel policy is now that userspace page tables are freed after an RCU grace period, and thus it is now safe to unconditionally perform page table walks under RCU, safe in the knowledge that page tables will not be freed underneath the walker. This is all that is guaranteed, however, so naturally it is still incumbent upon page table walkers to ensure that the page table entries are as expected. Link: https://lore.kernel.org/20260911-rcu-pagetable-freeing-v3-11-7b8c86103821@kernel.org Signed-off-by: Lorenzo Stoakes (ARM) Signed-off-by: Andrew Morton Acked-by: Kiryl Shutsemau (Meta) Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Andreas Larsson Cc: "Aneesh Kumar K.V" Cc: Anton Ivanov Cc: Arnd Bergmann Cc: Baolin Wang Cc: Barry Song Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Christian Zankel Cc: Dave Hansen Cc: David Hildenbrand Cc: David S. Miller Cc: Dev Jain Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Hugh Dickins Cc: Ingo Molnar Cc: James Bottomley Cc: Jason Gunthorpe Cc: Johannes Berg Cc: John Hubbard Cc: John Paul Adrian Glaubitz Cc: Jonas Bonn Cc: Lance Yang Cc: Liam R. Howlett Cc: Madhavan Srinivasan Cc: Magnus Lindholm Cc: Marc Rutland Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Hocko Cc: Michal Simek Cc: Mike Rapoport Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Peter Xu Cc: Peter Zijlstra Cc: Richard Henderson Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Ryan Roberts Cc: Stafford Horne Cc: Stefan Kristiansson Cc: Suren Baghdasaryan Cc: Sven Schnelle Cc: Thomas Bogendoerfer Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Vlastimil Babka Cc: WANG Xuerui Cc: Will Deacon Cc: Yoshinori Sato Cc: Zi Yan

mm: enable MMU_GATHER_RCU_TABLE_FREE for MMU riscv

2026-09-20T16:19:40+00:00

Currently riscv gates MMU_GATHER_RCU_TABLE_FREE on CONFIG_SMP and CONFIG_MMU. Commit 69be3fb111e7 ("riscv: enable MMU_GATHER_RCU_TABLE_FREE for SMP && MMU") enabled CONFIG_MMU_GATHER_RCU_TABLE_FREE for CONFIG_SMP, CONFIG_MMU riscv builds. This is expressly for the safety of GUP-fast walkers (CONFIG_HAVE_GUP_FAST is enabled if CONFIG_MMU is enabled). Naturally a single core system does not encounter issues with software page table walkers being correctly synchronised across cores, as there is only a single core. However, CONFIG_PREEMPT_RCU is still available on a riscv UP system, so for a future RCU-only page table walker, this guarantee is required to prevent concurrent page table teardown. All page table freeing is already done via tlb_remove_ptdesc() so the conditions of CONFIG_MMU_GATHER_RCU_TABLE_FREE are already met. This forms part of an overall effort to switch every architecture to this mode. Link: https://lore.kernel.org/20260911-rcu-pagetable-freeing-v3-3-7b8c86103821@kernel.org Signed-off-by: Lorenzo Stoakes (ARM) Signed-off-by: Andrew Morton Acked-by: Kiryl Shutsemau (Meta) Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Andreas Larsson Cc: "Aneesh Kumar K.V" Cc: Anton Ivanov Cc: Arnd Bergmann Cc: Baolin Wang Cc: Barry Song Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Christian Zankel Cc: Dave Hansen Cc: David Hildenbrand Cc: David S. Miller Cc: Dev Jain Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Hugh Dickins Cc: Ingo Molnar Cc: James Bottomley Cc: Jason Gunthorpe Cc: Johannes Berg Cc: John Hubbard Cc: John Paul Adrian Glaubitz Cc: Jonas Bonn Cc: Lance Yang Cc: Liam R. Howlett Cc: Madhavan Srinivasan Cc: Magnus Lindholm Cc: Marc Rutland Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Hocko Cc: Michal Simek Cc: Mike Rapoport Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Peter Xu Cc: Peter Zijlstra Cc: Richard Henderson Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Ryan Roberts Cc: Stafford Horne Cc: Stefan Kristiansson Cc: Suren Baghdasaryan Cc: Sven Schnelle Cc: Thomas Bogendoerfer Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Vlastimil Babka Cc: WANG Xuerui Cc: Will Deacon Cc: Yoshinori Sato Cc: Zi Yan

mm: make per-VMA locks available universally

2026-09-20T16:18:46+00:00

Patch series "mm: Unconditional per-VMA locks and cleanups", v7. tl;dr: Make per-VMA locks available in all configs. Simplify some of the per-VMA lock users now that they can rely on them being always available. Binder and networking folks: Your code is the target of the cleanups. I'm cc'ing you now on v2 because there's emerging consensus on the mm side that the approach here is sane. I'm not quite sure how this pile would get merged, but ack/review tags would be appreciated if this looks good to you. Longer version: When working on some x86 shadow stack code, it was a real pain to avoid causing recursive locking problems with mmap_lock. One way to avoid those was to avoid mmap_lock and use per-VMA locks instead. They are great, but they are not available in all configs which makes them unusable in generic code, or if you want to completely avoid mmap_lock. Make per-VMA locks available in all configs. Right now, they are only available on select architectures when SMP and MMU are enabled. But all of the primitives that per-VMA locks are built on (RCU, maple trees, refcounts) work just fine without SMP or MMU. The only real downside is that making VMAs a wee bit bigger on !MMU and !SMP builds. The upside is much cleaner code, lower complexity and less #ifdeffery. Clean up a binder VMA locking site now that it can rely on per-VMA locks. Building on top of universally-available per-VMA locks, introduce a new helper. Since the new API does not require callers to have a fallback to mmap_lock, it's much easier to use. Callers can potentially replace this very common kernel idiom: mmap_read_lock(mm); vma = vma_lookup() // fiddle with vma mmap_read_unlock(mm); with: vma = vma_start_read_unlocked(mm, address); // fiddle with vma vma_end_read(vma); Which avoids mmap_lock entirely in the fast path. Use that new API for another binder site and one in the TCP code. This patch (of 7): The per-VMA locks have been around for several years. They've had some bugs worked out of them and have seen quite wide use. However, they are still only available when architectures explicitly enable them. Remove the conditional compilation around the per-VMA locks, making them available on all architectures and configs. The approach up to now seemed to be to add ARCH_SUPPORTS_PER_VMA_LOCK when the architecture started using per-VMA locks in the fault handler. But, contrary to the naming, the Kconfig option does not really indicate whether the architecture supports per-VMA locks or not. It is more of a marker for whether the architecture is likely to benefit from per-VMA locks. To me, the most important thing side-effect of universal availability is letting per-VMA locks be used in SMP=n configs. This lets us use per-VMA locking in all x86 code without fallbacks. Overall, this just generally makes the kernel simpler. Just look at the diffstat. It also opens the door to users that want to use the per-VMA locks in common code. Doing *that* brings additional simplifications. The downside of this is adding some fields to vm_area_struct and mm_struct. There are likely ways to optimize this, especially for things like SMP=n configs. For now, do the simplest thing: use the same implementation everywhere. == Considerations for NOMMU config == NOMMU systems do not write-lock VMAs, therefore read-locking a VMA would always succeed unless VMA is detached. Therefore for NOMMU config we make vma_mark_attached() a NOOP, which keeps VMAs always in detached state. This causes VMA read-locking to always fail and the caller falls back to locking mmap_lock. The following functions will have a different implementation in NOMMU config: - vma_mark_attached(), vma_mark_detached() are made NOOPs, keeping VMAs always in a detached state and preventing assertions and refcount underflows; - vma_start_write(), vma_start_write_killable() are made NOOPs to avoid warnings in __vma_start_write() due to VMAs being detached. These functions are not used in NOMMU code but __vma_start_write() is an exported function, therefore might be used by drivers. - vma_assert_attached() is made NOOP because it's reachable from NOMMU code via split_vma()->vma_iter_store_new()->vma_iter_store_overwrite(); - vma_assert_write_locked() is asserting vma->vm_mm is write-locked, as was done before this change; - vma_assert_locked() is asserting vma->vm_mm is locked, as was done before this change; The following functions work for both MMU and NOMMU configs: - vma_lock_init() performs the same initialization as for MMU config; - mm_lock_seqcount_init(), mm_lock_seqcount_begin(), mm_lock_seqcount_end() are called from mmap_write_{lock|unlock} and update mm_lock_seq correctly. - mmap_lock_speculate_try_begin(), mmap_lock_speculate_retry() work as is because mm_lock_seq is updated correctly; - vma_start_read(), vma_start_read_locked() will always fail because VMAs are always detached; - vma_end_read() will never be called because vma_start_read() never succeeds; - vma_is_attached() always return false because VMAs are always detached; - vma_assert_detached() will never trigger because VMAs are never attached; - vma_start_read_locked() always return false because VMAs are always detached; - lock_vma_under_rcu() will be safe as the attempted read lock will bail; Changes in the following files are not affecting NOMMU config: task_mmu.c - not compiled when CONFIG_MMU=n; pagewalk.c - not compiled when CONFIG_MMU=n; userfaultfd.c - not compiled when CONFIG_MMU=n (CONFIG_USERFAULTFD depends on CONFIG_MMU); The following changes in the BPF code are made to keep NOMMU config working like before: stack_map_lock_vma() - keeps mmap_lock in NOMMU config; bpf_iter_task_vma_new() - bails out in NOMMU config; Link: https://lore.kernel.org/20260831203056.838265-1-surenb@google.com Link: https://lore.kernel.org/20260831203056.838265-2-surenb@google.com Signed-off-by: Dave Hansen Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton Reviewed-by: Lorenzo Stoakes (ARM) Acked-by: Vlastimil Babka (SUSE) Acked-by: David Hildenbrand (Arm) Cc: Liam R. Howlett Cc: Shakeel Butt Cc: Greg Kroah-Hartman Cc: Todd Kjos Cc: Christian Brauner Cc: Carlos Llamas Cc: Alice Ryhl Cc: David S. Miller Cc: David Ahern Cc: Arve Hjønnevåg

sched: dynamic: Remove HAVE_PREEMPT_DYNAMIC_{CALL,KEY}

2026-09-02T07:37:23+00:00

PREEMPT_DYNAMIC is now limited to the FULL and LAZY preemption models. Switching model only changes the behaviour of dynamic_preempt_lazy(), which uses a static key. There are no other static calls or static keys, and so there's no need for HAVE_PREEMPT_DYNAMIC_CALL or HAVE_PREEMPT_DYNAMIC_KEY. The static key used by dynamic_preempt_lazy() is entirely local to kernel/sched/core.c, and any architecture which selects ARCH_HAS_PREEMPT_LAZY implements the necessary support. Remove PREEMPT_DYNAMIC's dependencies on HAVE_PREEMPT_DYNAMIC_CALL and HAVE_PREEMPT_DYNAMIC_KEY entirely, leaving the dependency on ARCH_HAS_PREEMPT_LAZY. For architectures which previously selected HAVE_PREEMPT_DYNAMIC_KEY, PREEMPT_DYNAMIC will now be selected by default, matching x86. As the runtime impact is limited to dynamic_preempt_lazy(), this shouldn't be as concerning as previously (e.g. where calls to {cond,might}_resched() stubs could introduce a measurable penalty). As all of this can work without jump labels, JUMP_LABEL is not selected explicitly. It is obviously preferable to have JUMP_LABEL enabled, but this is not functionally necessary. Signed-off-by: Mark Rutland Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Jinjie Ruan Reviewed-by: Shrikanth Hegde Tested-by: Mete Durlu Tested-by: Shrikanth Hegde Tested-by: Jinjie Ruan Link: https://patch.msgid.link/20260803191731.3244294-6-mark.rutland@arm.com

riscv: bug: Make RV32 use GENERIC_BUG_RELATIVE_POINTERS

2026-09-01T01:11:23+00:00

x86 did this in commit b0a848f4a47a ("x86/bugs: Make i386 use GENERIC_BUG_RELATIVE_POINTERS") powerpc did this in commit 1baa1f70ef77 ("powerpc: Allow relative pointers in bug table entries") Similar as x86 and powerpc does, make RV32 use GENERIC_BUG_RELATIVE_POINTERS for "there is only one code path." and "less #ifdef is more better". Signed-off-by: Jisheng Zhang Link: https://patch.msgid.link/20260221024255.3552-1-jszhang@kernel.org Signed-off-by: Paul Walmsley

Merge tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-08-21T01:17:08+00:00

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 ...

Merge tag 'riscv-for-linus-7.3-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

2026-08-20T21:53:54+00:00

Pull RISC-V updates from Paul Walmsley - Add initial definitions and discovery for the Smcsrind, Sscsrind, Smcntrpmf, Ssccfg, Smcdeleg, Zicclsm, Ziccamoa, Ziccif, Ziccrse, Za64rs, and Ssqosid RISC-V ISA extensions - Improve the RISC-V update_mmu_cache_range() implementation by using flush-by-ASID, enabling performance improvements on microarchitectures that support related optimizations; and by taking advantage of the Svinval RISC-V ISA extension on microarchitectures that support it - Shrink CFI shadow stack allocation further (to 512MB) to save virtual address space (and physical memory on systems with strict overcommit policies) - Add initial CPU context switch support for QoS tagging (Ssqosid) - Change our vector misaligned access speed test code to be synchronous, avoiding a bunch of bugs related to unnecessary asynchronicity - Enable ARCH_HAS_ACPI_TABLE_UPGRADE for RISC-V to help with ACPI table debugging (similar to ARM64 and x86) - Extract vDSO section offsets at build time, rather than run time, to avoid the boot time overhead - Use assembler directives to control the use of instructions from the RISC-V ISA extensions Zacas and Zabha, rather than compiler -march flags that could affect the whole kernel (similar to ARM64) - Add a kselftest for kprobes support for the c.jal instruction on RISC-V - When UEFI runtime services are available, use them to restart and power off - Fix ARCH_HAS_ACPI_TABLE_UPGRADE for RISC-V by adding a missing include file to the ACPI code - Move contiguous DMA memory reservation later in the boot, to ensure that the correct global and per-node pools are allocated when CONFIG_CMA_SIZE_PERNUMA is enabled - Disallow probes on breakpoint handlers to avoid recursing indefinitely into do_trap_break() - Patch the compat vDSO during runtime alternatives processing, not only the standard vDSO - Remove some leftover XIP support elements missed by commit 9b3a2be84803 ("riscv: Remove support for XIP kernel") - Fix broadcast timer switching in ACPI LPI power states by implementing a RISC-V version of arch_get_idle_state_flags() - Miscellaneous fixes, including: vDSO makefile simplification; marking our default_power_off() as __noreturn; error path fixes in the PMU SBI perf driver; RISC-V extension capitalization consistency; the use of BIT() macros in one of our include files; and some documentation fixes * tag 'riscv-for-linus-7.3-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (39 commits) RISC-V: hwprobe: Use BIT macro to avoid warnings riscv: alternative: Also patch the compat vDSO riscv: alternative: Use the statically extracted vDSO section offsets riscv: vdso: Add symbols for the alternative section boundaries riscv: Add Ziccamoa, Ziccif, Ziccrse, and Za64rs to cpufeature and hwprobe riscv: Add Zicclsm to cpufeature and hwprobe riscv: cpufeature: Clarify ISA spec version for canonical order riscv: Standardize extension capitalization riscv: kprobes: Prevent probes in breakpoint handlers riscv: cmpxchg: Use .option arch for Zacas and Zabha riscv: acpi: Handle LPI architectural context loss flags riscv: further remove XIP riscv: Add support for srmcfg CSR from Ssqosid extension riscv: Detect the Ssqosid extension dt-bindings: riscv: Add Ssqosid extension description dt-bindings: riscv: add Counter delegation ISA extensions description RISC-V: Add Ssccfg/Smcdeleg ISA extension definition and parsing RISC-V: Add Ssccfg extension CSR definition dt-bindings: riscv: add Smcntrpmf ISA extension description RISC-V: Add Smcntrpmf extension parsing ...