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6 daysMerge tag 'mm-stable-2026-10-25-19-27' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "mm: make VMA flag semantics explicit, eliminate VM_SPECIAL" (Lorenzo Stoakes): Replace VM_SPECIAL with helpers describing mapping ownership and behavior. Enforce the mmap flag rules and convert affected drivers, removing ambiguous tests shared by driver mappings and ordinary memory. - "support kselftest on nommu platform" (Hajime Tazaki): Add opt-in mmap and mremap tests for NOMMU systems. Teach the runner to avoid its fork-dependent timeout command and document the build and runtime requirements. - "mm/collapse: separate a collapse from its callers" (Kiryl Shutsemau): Separate huge-page collapse from caller policy. Replace khugepaged identity checks with explicit permissions, and separate scanning from collapse with the mmap_lock drop in one place. - "mm: implement and use vma_has_anon_rmap(), silence KCSAN" (Lorenzo Stoakes): Provide a common helper for testing whether a VMA has anonymous reverse mappings. Document the locking rules, annotate intentional concurrent reads for KCSAN, and convert the core MM callers. - "mm/sparse: remove SECTION_MARKED_PRESENT and further cleanups" (David Hildenbrand): Remove SECTION_MARKED_PRESENT in favor of the early-section flag. Simplify sparse memory initialization, section metadata handling and related PFN validity checks. - "sh: remove NUMA and SPARSEMEM support" (Mike Rapoport): Remove SuperH NUMA and SPARSEMEM support. The extra memory banks have been unusable since the NO_BOOTMEM conversion, leaving only the code and data overhead. - "mm: Unify device DAX and HugeTLB vmemmap population paths" (Muchun Song): Unify the generic device DAX and HugeTLB vmemmap population paths and shared tail-page handling. Remove the duplicate DAX machinery while retaining the powerpc radix implementation. - "kselftest: mm: fix some failure of split_huge_page_test" (Yeoreum Yun): Fix huge-page split tests racing with khugepaged recollapse. Use pagemap and page flags instead of VMA-boundary assumptions which fail when glibc has already enabled THP. - "memcg: move memcgid refcount to objcg to unpin dying memcgs" (Bingfang Guo): Let dying memcgs be freed while swapped-out shmem still holds their IDs. Move ID references to reparentable objcgs, with the necessary swap accounting and RCU lifetime changes. - "mm/truncate: fix data loss when truncating straddling large folios" (Zhang Yi): Preserve out-of-range data when truncating straddling large folios. Fix a lookup race and split-failure handling, and handle minimum folio orders for the forthcoming ext4 iomap buffered I/O path. - "mm/damon: introduce damos quota goal target metric complement flag" (SJ Park): Let DAMOS quota goals use a metric's complement, so utilization can also express free-memory goals without adding separate metrics. Add the sysfs interface, documentation and tests. - "arm64/mm: Standardize printing for pgtable entries" (Anshuman Khandual): Use the generic formatter for arm64 page-table entries, ready for future wider entries. Move the safe-PTE-update check out of the header to avoid an include cycle. - "mm: kmsan: fix iounmap metadata teardown" (Dima Koziuk): Fix KMSAN metadata leaks on iounmap and failed ioremap allocations. Free backing pages before removing their mappings, and share the teardown with partial-allocation cleanup. - "mm/damon/core: preserve quota state when constructing schemes" (Karl Mehltretter): Preserve running DAMOS quota state while validating parameter updates. Even rejected updates could reset accounting and exceed the quota window; add tests for both accepted and rejected updates. - "mm/vmalloc: fix vmalloc_dump_obj VA lookup" (Ye Liu): Fix vmalloc_dump_obj() lookups for last-page addresses and allocations spanning vmap zones. These allocations were being missed in diagnostic output. - "mm: various (urgent?) fixes" (David Hildenbrand): Fix mmap charge leaks and hugetlb use-after-free, wrong-address unmapping, stuck locks and endless faults. Also preserve reservations on failed mremap and handle stale userfaultfd bits. - "maple_tree: fix maple_range_64 crashes in RCU mode" (Dimitris Charisis): Fix pointer and metadata confusion during RCU destruction of maple_range_64 nodes, avoiding double frees and invalid accesses. Add a regression test; no in-tree user currently uses this combination. - "mm: fix hugetlb NR_HUGETLB accounting on folio migration" (Hongfu Li): Fix hugetlb migration and preallocation accounting so /proc/vmstat retains the correct count and memory.numa_stat follows the folio to its new node. - "mm/damon: fix a minor bug, clean code, and add a test" (SJ Park): Fix 32-bit DAMON age overflow which made old regions look young. Share hugetlb folio acquisition code and add a regression test for the previously fixed last-region skipping bug. - "mm/damon/core: cleanup code, reduce stack usage, and add kunit" (SJ Park): Reduce kdamond stack usage and remove unused enums. Add deterministic PSI quota-goal tests which do not depend on the machine's current memory pressure. - "mm/damon: fix the temporal goal tuner's size quota conversion" (Donggeun Yoo): Bound the temporal tuner's quota conversion to prevent overflow and zero effective quotas, which could stop schemes making progress. Add boundary tests. - "Don't use GFP_DMA when calling dma_alloc_coherent" (Baoquan He): Remove redundant GFP_DMA flags from coherent DMA allocation calls. The DMA API already selects the zone from device limits and ignores the caller's flag. - "kselftest: mm: fix intermittent failure khugepaged test" (Yeoreum Yun): Propagate child-process failures in the khugepaged tests and prevent background collapse from racing their checks. This removes false passes and intermittent failures. - "MAINTAINERS: cover all hugetlb headers under HUGETLB SUBSYSTEM" (Enze Li): Cover all hugetlb headers in MAINTAINERS so get_maintainer.pl finds the right maintainers. Also label the closing hugetlb_cgroup.h include guard. Summary of the 65 singletons in this merge: The singletons include a few worthwhile performance fixes. Avoiding unnecessary reverse-map tree updates gave a reported 15.9% improvement in UnixBench's execl test on a 192-core x86 system. A reclaim retry fix stops defrag_mode from spinning under memory.low protection; a reported file-creation stress test ran 5.7 times faster, with far less memory pressure. Narrower hugetlb invalidations also spare KVM guests needless refaults: the reported Redis-in-VM P99 QPS penalty while punching holes fell from 7.09% to 1.45%. Several fixes prevent lost data or corrupted memory. Lazyfree huge-page races with mremap()/munmap() could lose data or access freed memory, and MADV_COLD could lose a concurrent write's dirty bit. Another fix prevents stale migration entries from outliving large folios. On filesystems with blocks smaller than a page, extending a file by 4 GiB or more could expose bytes written past the old EOF through mmap instead of zeroes. That is fixed, along with use-after-free races in PAGEMAP_SCAN during process exit and in memory-cgroup accounting on PREEMPT_RT kernels. Other fixes stop UFFDIO_MOVE spinning forever on pinned large folios, which could wedge other memory operations, and stop mremap() leaking commit charges until allocations fail under strict overcommit. A further fix keeps userfaultfd tracking intact on neighboring mappings. NUMA binding no longer prevents long-term pins when the chosen node has only movable memory, fixing QEMU/VFIO startup and io_uring buffer registration failures. MGLRU also gets a fix for early-boot crashes with memory cgroups disabled at boot, notably in small crash kernels. * tag 'mm-stable-2026-10-25-19-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (213 commits) mm: multi-gen LRU: fix NULL lruvec->pgdat deref with memcg disabled on cmdline mm/page_counter: use WRITE_ONCE() for emin/elow when parent is the root mm/memcontrol: publish null pointer before dropping css reference test_maple_tree: test maple_range_64 node in RCU mode maple_tree: fix maple_range_64 crashes in RCU mode mm/vma: avoid broken uffd merge on mremap tools/testing/shared: catch a failed posix_memalign() mm/damon/core: remove unreachable damos charge_{target,addr}_from mm/shrinker: allocate shrinker_info_unit from a dedicated kmem_cache riscv: mm: exclude invalid THP PMDs from page table check mm/damon/core: filter out damos address filter-split failed region fs/proc/task_mmu: pin mm_users in do_pagemap_scan() mm/mempolicy: apply bind policies against the scoped allocation zone mm/vmscan: reclaim every zone in per-node proactive reclaim mm/mremap: correctly uncharge accountable VMAs in error path mm/mremap: populate calculated fields in vrm state correctly MAINTAINERS: add an entry for MEMORY MANAGEMENT - MEMORY MAP mm: bdi: reset min_ratio after the sysfs attributes are gone mm/page_vma_mapped: continue past nonmatching huge PMDs selftests/mm: skip hugetlb cgroup v2 tests without the needed controllers ...
10 daysuprobes: remove VM_IO, set VM_MIXEDMAP for mapped kernel pagesLorenzo Stoakes (ARM)
These are not MMIO pages so VMA_IO_BIT is an inappropriate flag to set. Instead, set them VMA_MIXEDMAP_BIT as they are kernel mappings and this is the appropriate flag to set for those. This provides the semantics required - no VMA merging is permitted, but does not prevent GUP. However this has no meaningful impact as these are refcounted and thus can be GUPed. A previous commit already prevented __mm_populate() from being invoked on XOL areas, which VMA_IO_BIT was previously relied upon to do, so that is no longer required. Both VMAs set a VMA name, so always_dump_vma() returns true before vma_dump_size() reaches its VMA_IO_BIT check, and thus there is no change in core dump behaviour. Change this for both the core xol_add_vma() function and the x86-specific get_uprobe_trampoline() function. Link: https://lore.kernel.org/20261013-b4-mmap-prepare-vma-flag-sanify-v6-22-1aa3c9b139f9@kernel.org Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Liam R. Howlett <liam@infradead.org> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Mike Rapoport <rppt@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Leon Romanovsky <leon@kernel.org> Cc: Paul Moore <paul@paul-moore.com> Cc: Stephen Smalley <stephen.smalley.work@gmail.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Nico Pache <nico.pache@linux.dev> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Barry Song <baohua@kernel.org> Cc: Lance Yang <lance.yang@linux.dev> Cc: Usama Arif <usama.arif@linux.dev> Cc: Kiryl Shutsemau <kas@kernel.org> Cc: Doug Gilbert <dgilbert@interlog.com> Cc: James Bottomley <james.bottomley@hansenpartnership.com> Cc: Martin K. Petersen <mkp@kernel.org> Cc: Simona Vetter <simona@ffwll.ch> Cc: Helge Deller <deller@gmx.de> Cc: Sebastian Reichel <sre@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Peter Xu <peterx@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Rik van Riel <riel@surriel.com> Cc: Harry Yoo <harry@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: David Airlie <airlied@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Jan Kara <jack@suse.cz> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oupton@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Anup Patel <anup@brainfault.org> Cc: Paul Walmsley <pjw@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Janosch Frank <frankja@linux.ibm.com> Cc: Claudio Imbrenda <imbrenda@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Gregory Price <gourry@gourry.net> Cc: Ying Huang <ying.huang@linux.alibaba.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Chris Li <chrisl@kernel.org> Cc: Kairui Song <kasong@tencent.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Baoquan He <baoquan.he@linux.dev> Cc: Youngjun Park <youngjun.park@lge.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Qi Zheng <qi.zheng@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Wei Xu <weixugc@google.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Michal Hocko <mhocko@kernel.org> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Xu Xin <xu.xin@linux.dev> Cc: Ihor Solodrai <ihor.solodrai@linux.dev> Cc: Bert Karwatzki <spasswolf@web.de>
2026-10-19uprobes: Use get_user() in is_trap_at_addr()Linus Torvalds
is_trap_at_addr() reads the instruction at a user address with __get_user(), inside pagefault_disable() since the caller holds mmap_lock. There is no access_ok() in front of it, and nothing here needs the unchecked version: with page faults disabled, get_user()'s might_fault() check returns early, so that is no reason to avoid it either. Use get_user(), which also checks that the address is a user address, and on x86 avoids the lfence that __get_user() does. This is part of getting rid of __get_user() and __put_user() entirely. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-08-27Merge tag 'mm-stable-2026-08-26-15-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff" (Lorenzo Stoakes) Index MAP_PRIVATE file-backed folios by their anonymous page offset to resolve confusion around reverse mapping for zeroed and CoW'd file-backed memory. Use this new VMA anonymous page offset tracking to eliminate index conflicts and lay the foundation for scalable CoW performance improvements. - "promote mapped executable folios after first usage for MGLRU" (Baolin Wang) Make MGLRU's protection of mapped executable file folios more reliable. Follow the classical LRU's logic, promoting mapped executable file folios after their first usage to give executable code a better chance to stay in memory and improve workload performance. - "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong Chen) Fix per-node proactive reclaim interface's ignoring the swappiness parameter when CONFIG_MEMCG is disabled by consolidating sc_swappiness() into a single function that checks proactive_swappiness regardless of kernel configuration. - "mm/vmscan: reduce lru_lock contention via vmstat-derived scan-balance cost" (Usama Arif) Reduce lru_lock contention in the reclaim path by deriving scan-balance costs from vmstat counters rather than lock-acquired producer updates. Read and decay these cost signals on the reclaim side under a dedicated per-lruvec lock, reducing total LRU lock wait time by over 60% without impacting scan throughput. - "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky) Fix two low-risk zram bugs which Sashiko spotted in drive-by review. - "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's memcg" (Zi Yan) Fix xas_split_alloc() by enabling target folio memcg charging during splits and adding the missing __GFP_ACCOUNT flag for proper XArray node memory accounting. - "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick) Replace hardcoded binary names in selftests/mm/.gitignore with a generic pattern-matching rule to automatically ignore generated test files and avoid manual updates when adding new tests. - "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon) Make the incompatibility between FLATMEM and NUMA explicit in mm/Kconfig and remove the unused pgdat_page_ext_init() function. - "zram: fix zstd error paths and add parameter validation" (Haoqin Huang) Clean up zram compression backends by removing redundant error cleanup, adding parameter and dictionary validation, auto-prefixing algorithm error logs, and resetting parameters prior to reinitialization. - "zram: fix stale scan bounds after reinitialization" (Longlong Xia) Prevent out-of-bounds slot accesses during concurrent zram resets by moving table scan bound calculations under dev_lock in writeback_store() and read_block_state(). - "add anon mTHP collapse test cases" (Baolin Wang) Extend selftests helper functions to support arbitrary page orders and add new test cases and options for mTHP collapse in khugepaged. - "selftests/mm: Handle unsupported and transient test conditions" (Muhammad Usama Anjum) Update MM selftests to report a SKIP status instead of a failure when required kernel or filesystem features are unsupported, while adding retry logic for transient page migration errors. - "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia) Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled and extend shrink_memcg() to support batch writeback for improved writeback efficiency. - "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren Baghdasaryan) Introduce an IOCTL-based binary interface for memory allocation profiling that enables kernel-side filtering before per-CPU counter aggregation. This eliminates the text-parsing overhead of /proc/allocinfo and provides up to a 20x speedup by transferring only filtered allocation data to userspace. - "better block swap batching and a different take on swap_ops v5" (Christoph Hellwig) Refactor block swap I/O to use swap_iocb for batching instead of single-bio requests and rebase the swap_ops interface, achieving faster swap throughput during kernel builds. - "mm: kmemleak: reduce transient false positives by confirming leaks" (Catalin Marinas) Reduce false-positive kmemleak reports by combining two kmemleak enhancements that add a second confirmation scan and a configurable minimum unreferenced scan count module parameter. - "mm: kmemleak: default min_unref_scans to 2 for verbose kernels" (Breno Leitao) Auto-scanning kernels can generate false-positive memory leak reports on single scans, so this patch defaults min_unref_scans to 2 when CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second confirming scan. - "swap_ops updates" (Christoph Hellwig) Batching I/O for synchronous swap devices causes performance regressions and filesystem-based swap suffers from double-indirection overhead. This series resolves both issues by reintroducing per-folio writes for synchronous swap and allowing filesystems to directly export their own swap_ops. - "mm/khugepaged: several cleanups" (Nico Pache) khugepaged accumulated redundant state-checking patterns and outdated comments following mTHP integration. Introduce dedicated helpers for PTE validation and event counting while refreshing the internal documentation. - "maple_tree: lock checking and clean ups" (Liam Howlett) Syzbot reports incorrectly blame memory management exit paths for locking bugs, maple tree erase operations risk allocation failures without gfp flags and internal documentation lacks clarity. Improve lock error detection, update docs, fix race and allocation edge cases and optimize erase allocations using a fallback to GFP_KERNEL | GFP_NOFAIL. * tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (172 commits) selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC memcg: move LRU size accounting on reparenting instead of copying it mm/vmscan: fix comment logic in balance_pgdat maple_tree: add helper mas_make_walkable() maple_tree: avoid extra gap calculation maple_tree: fix argument name in header maple_tree: change two GFP flags in tests maple_tree: document erase and allocations better maple_tree: avoid mas_erase() and mtree_erase() failures maple_tree: document that erase may use GFP_KERNEL for allocations maple_tree: catch race in mas_alloc_cyclic() maple_tree: add bulk parent set helper maple_tree: micro optimisation of mas_wr_store_type() maple_tree: optimise mas_wr_node_store() when not in rcu mode maple_tree: use prefetched value in mas_wr_store_type() maple_tree: clarify comments on mas_nomem() maple_tree: drop MAPLE_ALLOC_SLOTS maple_tree: drop dead code from mas_extend_spanning_null() maple_tree: documentation fix maple_tree: add write lock checking with lockdep sequence numbers ...
2026-08-24mm: provide vma_[flags_]is_cow_mapping() and remove is_cow_mapping()Lorenzo Stoakes (ARM)
All remaining callers of is_cow_mapping() are invoking it in the form of is_cow_mapping(vma->vm_flags) or an indirected version of this. Therefore, provide a helper - vma_is_cow_mapping() to directly test the VMA. Additionally provide a new helper vma_flags_is_cow_mapping() which performs the check using the new vma_flags_t type, and share this logic between vma_is_cow_mapping() and vma_desc_is_cow_mapping(). With these changes, no callers of is_cow_mapping() remain, so remove it. Also update the userland VMA tests to reflect the change. No functional change intended. [akpm@linux-foundation.org: fix kerneldoc comment typo, per Lorenzo] Link: https://lore.kernel.org/aob1goSSPH6sTN9y@gremlin Link: https://lore.kernel.org/20260813-b4-scalable-cow-virt-pgoff-v5-2-c21581c0c3c8@kernel.org Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Deucher <alexander.deucher@amd.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <baoquan.he@linux.dev> Cc: Barry Song <baohua@kernel.org> Cc: Boris Brezillon <boris.brezillon@collabora.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chris Li <chrisl@kernel.org> Cc: Christan König <christian.koenig@amd.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Claudio Imbrenda <imbrenda@linux.ibm.com> Cc: Dave Airlie <airlied@gmail.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Gregory Price (Meta) <gourry@gourry.net> Cc: Harry Yoo <harry@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huang Ray <Ray.Huang@amd.com> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Janosch Frank <frankja@linux.ibm.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Kairui Song <kasong@tencent.com> Cc: Kees Cook <kees@kernel.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam R. Howlett <liam@infradead.org> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Marc Rutland <mark.rutland@arm.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Maxime Ripard <mripard@kernel.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Namhyung kim <namhyung@kernel.org> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nico Pache <npache@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Rik van Riel <riel@surriel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Steven Price <steven.price@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Thomas Zimemrmann <tzimmermann@suse.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-20Merge tag 'mm-stable-2026-08-18-18-39' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "mm: drop "sub" prefix from various places" (Dev Jain) page->folio conversion and a naming cleanup - "mm/kasan: remove redundant initialization for kasan_flag_write_only" (Igor Putko) KASAN cleanup work - "mm/filemap: reduce unnecessary xarray lookups" (Chi Zhiling) Small speedup in the pagecaache read code - "mm/percpu: Fix possible NOFS/NOIO reclaim recursion" (Kaitao Cheng) Improve the vmalloc code - mainly the avoidance of GFP_KERNEL allocations when the caller asked for GFP_NOFS or GFP_NOIO - "mm/kmemleak: avoid soft lockup when scanning task stacks" (Breno Leitao) Avoid a soft lockup watchdog trigger from the kmemleak scanning code in extreme situations - "mm/page_owner: misc cleanups" (Ye Liu) Cleanups to the page_owner code. For some reason lots of people have been working on the page_owner code this cycle. - "mm: convert to walk_page_range_vma() to eliminate find_vma()" (Kefeng Wang) Simplify and accelerate the page walking library function - "mm/migrate: preparatory cleanups for batch copy and offload" (Shivank Garg) Cleanups in the migration code - "mm/page_owner: add per-fd filter infrastructure for print_mode and NUMA filtering" (Zhen Ni) Per-fd filtering to page_owner in order to reduce the sometimes vast amount of output it can produce - "mm: Refactor bootmem gigantic hugepage allocation" (Muchun Song) Fixes and preparatory cleanups around bootmem HugeTLB handling, sparse initialization ordering, and related vmemmap setup - "mm/zsmalloc: reduce lock contention in zs_free()" (Wenchao Hao) Reduce lock contention in zs_free(), which dominates the unmap path under memory pressure on Android (LMK kills) and on x86 servers running zswap-heavy workloads. Up to 1.83x improvement in microbenchmarking. - "move alloc_tag.c file under mm/" (Suren Baghdasaryan) - "samples/damon: handle damon_{start,stop}() failures" (SJ Park) Fix improper handling of damon_start(), damon_stop(), and damon_call() failures across DAMON sample modules to prevent potential memory leaks, operation disruptions and use-after-free bugs - "mm/damon/sysfs: kobject_del() directories that users can create/remove" (SJ Park) Fix delayed sysfs directory removal under DEBUG_KOBJECT_RELEASE causeing creation failures due to duplicate directory names by adding missing kobject_del() calls before creating new directories - "mm: cleanup clear_not_present_full_ptes()" (David Hildenbrand) Clean up the core pte handling code - "selftests/damon: misc fixes for test bugs" (Kunwu Chan) Fix several bugs in the DAMON selftests - "selftests/damon: fix memcg_path staging handling" (Cheng Nie) Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and add a test case for it in sysfs.py. - "selftests/damon: test kdamond refresh_ms" (Ruslan Valiyev) Selftest coverage for DAMON's refresh_ms sysfs feature by updating the test control module and verifying that scheme stats update automatically without manual intervention - "mm/damon: five misc fixups" (Akinobu Mita) Miscellaneous DAMON fixups. - "mm/damon/core: detect internal variation above max_nr_regions/2" (Jiayuan Chen) Fix DAMON's region splitting behavior when region counts exceed half the maximum budget by dynamically scaling down the split fraction as the limit approaches, preventing large regions from staying un-split, and add corresponding KUnit test coverage - "mm: preparatory patches for PMD level swap entries" (Usama Arif) Refactor and clean up PMD softleaf helpers, call sites, and architecture flags to lay the groundwork for a follow-up series that introduces PMD page table swap entries - "mm/damon: update, optimize, and clean up doc, tests, and code" (SJ Park) Update DAMON design and ABI documentation, expands unit and selftest coverage, optimize damon_commit_target_regions(), and clean up recently added sysfs interface code for better readability - "mm/vmpressure: reduce CPU, memory and code overhead on cgroup v2" (Usama Arif) Optimize vmpressure() by skipping unnecessary work on cgroup v2 for userspace event notifications and refactor v1-only eventfd handling into mm/memcontrol-v1.c to reduce memory overhead and code complexity - "selftests/mm: refactor pkey helpers and fix mmap error handling" (Hongfu Li) Refactor pkeys shared tracing and assertion helpers into a common file, unify protection key selftests to use consistent diagnostic logging and assertions, and enforce standardized MAP_FAILED return checks for mmap() calls across the tests - "mm/damon: optimize out nr_accesses_bp" (SJ Park) Replace the error-prone, continuously updated nr_accesses_bp field in damon_region with an on-demand moving sum function, reducing structure memory overhead and avoiding state corruption bugs - "Open HugeTLB allocation routine for more generic use" (Ackerley Tng) Decouple HugeTLB folio allocation from VMA dependencies by introducing hugetlb_alloc_folio(), enabling subsystems like guest_memfd to allocate HugeTLB folios without standard VMA reservations or pseudo-VMAs - "mm/damon: provide pseudo moving sum probe_hits" (SJ Park) Integrate DAMON's probe_hits attribute counter into the pseudo moving sum infrastructure, enabling real-time, online monitoring without waiting for full aggregation intervals - "mm: Some cleanups for page allocator APIs" (Brendan Jackman) Simplify and refactor the page allocator entry points and flags by unifying allocation paths, adding internal alloc_flags arguments, and eliminating redundant __ prefixed alloc_pages variants. - "Fix incorrect access of hugetlb pte entries" (Dev Jain) Enforce the consistent use of huge_ptep_get() instead of ptep_get() for HugeTLB entries and fixes an unaligned address issue in arm64's huge_ptep_get() implementation - "mm/damon: validate all parameters in the core" (SJ Park) Consolidate parameter validation into the DAMON core specifically within damon_start() and damon_commit_ctx() to centralize error checking, eliminate caller-side redundant checks and to improve maintenance efficiency - "tools/mm/page_owner_sort: fix filtering and cleanup issues" (Yichong Chen) Rename is_need() to filter_record() for clearer return semantics, fix per-record allocation memory leaks and bound output copies in search_pattern() to address an existing buffer issue - "memcg: bail out reclaim when memcg is dying" (Jiayuan Chen) Mitigate a system-wide stall which occurs when a cgroup is removed while one of its memory control files is doing synchronous reclaim - "mm/memory-failure: add panic option for unrecoverable pages" (Breno Leitao) Introduce an opt-in vm.panic_on_unrecoverable_memory_failure sysctl that immediately panics the kernel on unrecoverable memory errors in kernel-owned pages to preserve error context and prevent delayed, silent data corruption - "mm/damon: refactor damon_{start,stop,commit}() for simple error handling" (SJ Park) Refactor the DAMON core API functions to guarantee that all contexts are fully stopped when damon_start(), damon_stop(), or damon_commit() fail, eliminating the need for complex and error-prone caller-side cleanup code - "Keep tail page private zero at free and folio split" (Zi Yan) Add checks to ensure tail_page->private is zero when freeing compound or high-order pages and when promoting tail pages during large folio splits. By validating these fields at free and split time, it allows the removal of redundant private field clearing inside prep_compound_tail() - "mm: drop redundant lru_add_drain in anon folio reuse paths" (Barry Song) Eliminate redundant lru_add_drain() calls in wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock contention and system overhead By validating folio refcounts against the LRU cache before draining and removing unnecessary drains in the swap path, it achieves up to a 30.5% reduction in drain calls during heavy swap workloads - "mm: clean up folio LRU and swap declarations" (Jianyue Wu) Reorganize folio LRU and swap code by relocating page-cluster state to mm/swap_state.c, renaming mm/swap.c to mm/folio.c, and moving MM-internal reclaim declarations into mm/internal.h. - "userfaultfd: working set tracking for VM guest memory" (Kiryl Shutsemau) Add userfaultfd support for tracking the working set of VM guest memory, so a VMM can identify hot pages and reclaim cold ones to tiered or remote storage - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 2)" (David Hildenbrand) Remove the remaining pieces of CONFIG_HAVE_BOOTMEM_INFO_NODE, performing some smaller cleanups around freeing of reserved vmemmap pages on the way. - "mm/damon: update probe hits for runtime parameter commits" (SJ Park) Ensure that DAMON's probe_hits attribute counter is properly updated when monitoring intervals are changed at runtime, matching the behavior of nr_accesses. To achieve this, it refactors and renames existing helper functions for shared use, applies the updates to probe_hits, and handles edge cases in damon_probe_hits_mvsum() to maintain measurement accuracy. - "KSM: performance optimizations for rmap_walk_ksm" (xu xin) Resolve a severe KSM reverse-mapping performance bottleneck where thousands of split VMAs sharing a single anon_vma cause extended lock contention. By adding an interval-filtering check during the rmap walk, it reduces worst-case anon_vma lock hold times from over 500ms down to under 2ms, preventing application freezes and latency spikes under memory pressure. - "mm: split a couple of headers from internal.h" (Mike Rapoport) Split declarations related to mm_init, memblock, vmalloc and sparse into new headers - "KSM: use linear_page_index in collect_procs_ksm()" (xu xin) Apply the interval tree optimization from rmap_walk_ksm() to collect_procs_ksm() to avoid iterating over non-matching VMAs during KSM memory error handling. It hoists loop-invariant address initialization and restricts the anon_vma_interval_tree_foreach walk to a targeted page offset range, reducing redundant checks and improving lookup efficiency. - "selftests/mm: avoid false failures in hugetlb and KSM tests" (Sayali Patil) Fix issues in the hugetlb and KSM MM selftest categories that can report failures when the prerequisites for the tests are not satisfied - "mm/damon: introduce data attributes only monitoring" (SJ Park) Introduce attribute-weighted region management in DAMON, allowing users to prioritize specific data attributes (such as page sizes or cgroups) over or instead of access monitoring. By assigning weights to attribute probes, DAMON can completely disable access tracking and adjust monitoring regions based on weighted probe-hit counters to optimize monitoring quality for attribute-focused workloads. - "mm/hmm: Add mmap lock-drop support for userfaultfd-backed mappings" (Stanislav Kinsburskii) Extend hmm_range_fault() to support userfaultfd-backed regions by allowing the mmap lock to be dropped during fault handling via a new hmm_range_fault_locked() helper. By accepting a locked pointer and signaling retry status when lock release occurs, it enables page fault resolution in userfaultfd regions while preserving backward compatibility for existing callers. - "mm: make VMA page offset handling more consistent" (Lorenzo Stoakes) Clean up and standardize how vma->vm_pgoff is accessed and manipulated across file-backed and anonymous mappings in the kernel It introduces dedicated helper functions such as vma_start_pgoff(), vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while renaming rmap interval tree helpers to better reflect their functionality. These changes establish a cleaner foundation for future work that will unify virtual page offset indexing for all anonymous and CoW'd folios. - "mm: handle device-private PMDs in walk callbacks" (Usama Arif) Address kernel panics and state corruption caused by MM walk callbacks reaching non-present device-private PMD swap entries created during HMM migrations It ensures that functions which acquire pmd_trans_huge_lock() properly recognize device-private PMDs instead of assuming a present THP or a standard migration entry. - "mm/rmap: Refactor try_to_unmap_one" (Dev Jain) Refactor try_to_unmap_one by modularizing Hugetlb, anonymous-lazyfree, and anonymous-swapbacked logic into dedicated functions, laying the structural groundwork for batched anonymous large folio unmapping. - "Docs/ABI/damon: sysfs ABI document fixes and additions" (Song Hu) Fix typos and fills in missing entries in the DAMON sysfs ABI document - "dax/kmem: atomic whole-device hotplug via sysfs" (Gregory Price) Introduce an atomic sysfs state attribute and supporting DAX/MM infrastructure to prevent userland races when offlining and removing entire memory regions By adding an unplugged state alongside standard online modes, it enables whole-device atomic hotplug control while preserving backward compatibility. - "mm: convert more vm_flags_t users to vma_flags_t" (Lorenzo Stoakes) Continue transitioning the kernel from the deprecated vm_flags_t type to vma_flags_t across core memory management infrastructure. It replaces legacy type usage in core functions such as do_mmap(), unmapped area allocation, mm->def_vma_flags, and VMA operations like mlock, mprotect, and mremap. - "Two small patches to clean up mm/mm_slot.h" (xu xin) Refactor mm_slot.h by introducing mm_slot_remove() to unify duplicate slot deletion sequences in khugepaged and KSM. It also adds code documentation explaining why mm_slot_lookup and mm_slot_insert must remain as preprocessor macros rather than static inline functions. - "mm/damon/core: hide core-private struct fields" (SJ Park) Clean up DAMON core structures by consistently marking internal-only fields with private: comment tags to prevent improper direct access from outer layers. It enforces encapsulation across core structures including damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to interact through approved access APIs instead of exposing raw struct members. - "mm/damon: unurgent fixes for infinite loop, NULL de-ref and races" (SJ Park) Address potential infinite loops, NULL dereferences, and race conditions identified in DAMON It fixes an infinite loop triggered by extreme user configurations, a NULL pointer dereference within unit tests and minor monitoring accuracy degradation caused by subtle runtime races. - "mm/page_alloc: fixes for free_pages_nolock() on RT/UP" (Brendan Jackman) Fix an NMI safety flaw in __free_frozen_pages() where freeing pages on non-SMP or PREEMPT_RT kernels can bypass can_spin_trylock() checks via non-PCP or isolated migration paths. It also resolves potential kernel crashes and privilege escalation risks triggered when BPF tracing runs in NMI context alongside memory hotplug or large allocation frees. - "mm/page_alloc: couple of followups for recent cleanups" (Brendan Jackman) Clean up and update page allocator nomenclature, documentation, and debug assertions. It aligns internal FPI_ flags with the public "nolock" naming convention, removes outdated internal implementation details from high-level page allocator comments, and eliminates obsolete VM_BUG_ON() assertions in allocation paths. - "mm/mseal: further cleanups" (Lorenzo Stoakes) Refactor and simplify the mseal implementation by clarifying API boundaries and removing unnecessary code complexity. It replaces generic do_mseal() usage outside the syscall with a dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO, eliminates mm_struct parameters to enforce that sealing applies only to current->mm, and streamlines overall logic and comments with no functional changes intended. - "mm/vmscan: fix swappiness=max and clean up per-node proactive reclaim" (Ridong Chen) Resolve reclaim behavior bugs and clean up function parameters across memory reclaim paths It fixes swappiness=max in both standard reclaim and MGLRU so unswappable anonymous memory no longer falls back to evicting page cache, ensures reclaim_store() returns accurate error codes instead of collapsing all failures into -EAGAIN, and removes the obsolete gfp_mask parameter from __node_reclaim(). - "mm: mincore: misc cleanups" (Kefeng Wang) Clean up and simplifies the mincore code. Most importantly, it removes the historical special behavior that always reports VM_PFNMAP pages as non-resident. - "mm/huge_memory: drop dead split helper variants" (Kiryl Shutsemau) Two trivial cleanups in the folio split API - "mm/damon: fix uninitialized DAMOS field and kunit exec expectation bugs" (SJ Park) Resolve minor operational and testing bugs in DAMON identified by Sashiko. It initializes the damos->last_applied field to prevent occasional efficiency degradation and fixes invalid memory accesses in DAMON KUnit tests during test failure handling. - "cleanup for stable_page_flags()" (Jinjiang Tu) Clean up and refactor stable_page_flags() used by /proc/kpageflags without altering functionality. It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag bits, converts folio-specific flag checks to standard folio_test_*() helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling. - "Batch unmap of uffd-wp file folios" (Dev Jain) Extend batched folio unmapping support to file folios within userfaultfd write-protect (uffd-wp) VMAs by adding batching capabilities to pte_install_uffd_wp_if_needed(). This removes special-case restrictions on uffd-wp VMAs in try_to_unmap_one(), significantly simplifying the function's control flow and complexity. - "mm/early_ioremap: clarify and clean up early_ioremap_reset()" (Sang-Heon Jeon) Clarify and clean up the architecture-specific usage of __late_set_fixmap() and __late_clear_fixmap() after early_ioremap_reset() It adds explicit documentation regarding when early_ioremap_reset() must be called and removes redundant macro definitions and reset calls in the RISC-V and ARM64 architectures. - "mm: fix reclaim storms in defrag_mode" (Johannes Weiner) Address severe performance regressions, swap storms, and spurious OOMs caused by vm.defrag_mode=1 under high memory pressure in Meta production It updates the page allocator slowpath so non-movable allocation requests actively trigger direct reclaim and direct compaction at pageblock_order scale, allowing them to claim whole pageblocks rather than spinning unproductively. - "zram: lockmap tweaks" (Sebastian Siewior) Optimize and fix lockdep tracking for zram devices by consolidating per-entry lockmaps and isolate lock classes across multiple instances This reduces memory overhead by replacing per-entry lockdep_map instances with a single map per struct zram, and assigns a dynamic lock_class_key to each instance to prevent false deadlock reports when different zram devices are backed by distinct filesystems. * tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (501 commits) selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check selftests/mm: unpoison pages in memory-failure teardown mm/shmem: downgrade final i_blocks check in shmem_evict_inode() to pr_warn() mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro mm/zsmalloc: fix release order of locks in zs_page_migrate() Documentation: zram: remove sections numbering ksm: stop iterating VMAs when ksm_test_exit returns true mm: fold userfaultfd_rwp() to false without CONFIG_ARCH_HAS_PTE_PROTNONE mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() zram: use a custom key for each zram object zram: move lockmap to be per-zram instead per table selftests/mm: fix gup_longterm EINVAL error message mm: page_alloc: fix non-movable reclaim storm in defrag_mode mm: page_alloc: move capture_control to the page allocator mm: compaction: support non-movable compaction for pageblock requests mm: page_alloc: __GFP_FS lockdep annotation for direct compaction hugetlb: evaluate subpool free state while locked mm/damon: remove trailing semicolons after function definitions mm/damon/ops-common: prevent migration fallback to non-target nodes mm/damon: update outdated comment about DAMOS filter handling ...
2026-08-04mm: prefer vma_[start,end]_pgoff() to vma->vm_pgoff in kernel/Lorenzo Stoakes
Be consistent in using vma_start_pgoff() and vma_end_pgoff(), which clearly indicates which part of the VMA the page offset refers to and aids greppability. This is part of a broader series laying the ground to provide a virtual page offset for MAP_PRIVATE-file backed anon folios. No functional change intended. Link: https://lore.kernel.org/20260710-b4-pre-scalable-cow-v2-19-2a5aa403d977@kernel.org Signed-off-by: Lorenzo Stoakes <ljs@kernel.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> # for kernel/dma Reviewed-by: Gregory Price <gourry@gourry.net> Acked-by: Pedro Falcato <pfalcato@suse.de> Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Cc: Ackerley Tng <ackerleytng@google.com> Cc: David Hildenbrand (Arm) <david@kernel.org> Cc: Kai Huang <kai.huang@intel.com> Cc: SJ Park <sj@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Liam R. Howlett (Oracle) <liam@infradead.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04mm/rmap: rename vma_interval_tree_*() to mapping_rmap_tree_*()Lorenzo Stoakes
The family of vma_interval_tree_() functions manipulate the address_space (which, of course, is generally referred to as 'mapping') reverse mapping, but are named the 'VMA' interval tree. VMAs may be mapped by an anon_vma, an address_space, or both. Therefore calling the mapping interval tree a 'VMA' interval tree is rather confusing. This is also inconsistent with the anon_vma_interval_tree_*() functions which explicitly reference the rmap object to which they pertain. Rename the vma_interval_tree_*() functions to mapping_rmap_tree_*() to correct this. We will rename the anon rmap functions similarly in a subsequent patch. No functional change intended. Link: https://lore.kernel.org/20260710-b4-pre-scalable-cow-v2-8-2a5aa403d977@kernel.org Signed-off-by: Lorenzo Stoakes <ljs@kernel.org> Reviewed-by: Gregory Price <gourry@gourry.net> Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Ackerley Tng <ackerleytng@google.com> Cc: David Hildenbrand (Arm) <david@kernel.org> Cc: Kai Huang <kai.huang@intel.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: SJ Park <sj@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Liam R. Howlett (Oracle) <liam@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04mm/rmap: parameterise vma_interval_tree_*() by address_spaceLorenzo Stoakes
The file-backed mapping interval tree functions vma_interval_tree_*() accept a raw rb_root_cached pointer to determine the tree in which they are operating. However, in each case, this is always associated with an address_space data type. So simply pass a pointer to that instead to simplify the code, and more clearly differentiate between these operations and those concerning anonymous mappings. While we're here, make the generated interval tree functions static as they do not need to be used externally (any previously existing external users have now been removed). We also rename VMA parameters from 'node' to 'vma' as calling this a node is simply confusing, update the input index types to pgoff_t since they reference page offsets and rename the parameters to pgoff_start and pgoff_last. No functional change intended. Link: https://lore.kernel.org/20260710-b4-pre-scalable-cow-v2-6-2a5aa403d977@kernel.org Signed-off-by: Lorenzo Stoakes <ljs@kernel.org> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Reviewed-by: Gregory Price <gourry@gourry.net> Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Ackerley Tng <ackerleytng@google.com> Cc: David Hildenbrand (Arm) <david@kernel.org> Cc: Kai Huang <kai.huang@intel.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: SJ Park <sj@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Liam R. Howlett (Oracle) <liam@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-03uprobes: Switch uretprobes_srcu to SRCU-fast-updownPuranjay Mohan
uretprobes_srcu currently uses normal SRCU, which issues two smp_mb() per read lock/unlock pair. This overhead is paid on every uretprobe hit. Switch to SRCU-fast-updown, which eliminates the per-reader memory barriers by moving the ordering cost to the grace-period side (synchronize_rcu() instead of smp_mb()). This is acceptable because grace periods (uprobe unregistration) are infrequent compared to reader-side uretprobe hits. The updown flavor is required because the SRCU read lock is taken in prepare_uretprobe() when a return instance is created and is held until that return instance is finalized. The traced thread returns to user space in between, so the lock is inherently released in a different context from where it was acquired: on the normal return path via uprobe_handle_trampoline() -> hprobe_finalize(), or from ri_timer() (expiry) or dup_utask() (fork) via hprobe_expire(). srcu_down_read_fast() / srcu_up_read_fast() are designed for this acquire-here / release-elsewhere pattern and, unlike the same-context srcu_read_lock_fast() variant, do not carry the lockdep read-side tracking that would warn on it. The short, same-context SRCU sections in ri_timer() and dup_utask() (which guard the uprobe against reuse across the hprobe_expire() cmpxchg) instead use guard(srcu_fast_updown) for proper lockdep coverage. Signed-off-by: Puranjay Mohan <puranjay@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://patch.msgid.link/20260706172744.3920417-3-puranjay@kernel.org
2026-07-31Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2026-07-31uprobes: Fix NULL pointer dereference in hprobe_expire()Breno Leitao
Forking a task that has a pending uretprobe can oops the kernel with a NULL pointer dereference in the clone() path: BUG: kernel NULL pointer dereference, address: 0000000000000018 Oops: 0002 [#1] SMP NOPTI RIP: 0010:hprobe_expire CR2: 0000000000000018 Call Trace: uprobe_copy_process copy_process kernel_clone __x64_sys_clone do_syscall_64 entry_SYSCALL_64_after_hwframe This was found on real hosts on Meta fleet. I've got the impression that this is what is happening: CPU 1 CPU 2 (traced task) ----- ------------------- hit uprobe, prepare_uretprobe(): hprobe LEASED, refcount >= 1 uprobe_unregister() put_uprobe(): refcount -> 0 fork() -> dup_utask() hprobe_expire(hprobe, true) try_get_uprobe() -> NULL get_uprobe(NULL) <-- Oops Only take the extra reference when the uprobe is non-NULL; a NULL means it is gone and is the correct value to return. Fixes: dd1a7567784e ("uprobes: SRCU-protect uretprobe lifetime (with timeout)") Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260729-uprobe-v1-1-61896b87c867@debian.org
2026-07-03uprobes/x86: Remove struct uprobe_trampoline objectJiri Olsa
Removing struct uprobe_trampoline object and it's tracking code, because it's not needed. We can do same thing directly on top of struct vm_area_struct objects. This makes the code simpler and allows easy propagation of the trampoline vma object into child process in following change. Note the original code called destroy_uprobe_trampoline if the optimiation failed, but it only freed the struct uprobe_trampoline object, not the vma. The new vma leak is fixed in following change. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://patch.msgid.link/20260703114917.238144-3-jolsa@kernel.org
2026-03-06treewide: change inode->i_ino from unsigned long to u64Jeff Layton
On 32-bit architectures, unsigned long is only 32 bits wide, which causes 64-bit inode numbers to be silently truncated. Several filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that exceed 32 bits, and this truncation can lead to inode number collisions and other subtle bugs on 32-bit systems. Change the type of inode->i_ino from unsigned long to u64 to ensure that inode numbers are always represented as 64-bit values regardless of architecture. Update all format specifiers treewide from %lu/%lx to %llu/%llx to match the new type, along with corresponding local variable types. This is the bulk treewide conversion. Earlier patches in this series handled trace events separately to allow trace field reordering for better struct packing on 32-bit. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org Acked-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-02uprobes: Fix incorrect lockdep condition in filter_chain()Breno Leitao
The list_for_each_entry_rcu() in filter_chain() uses rcu_read_lock_trace_held() as the lockdep condition, but the function holds consumer_rwsem, not the RCU trace lock. This gives me the following output when running with some locking debug option enabled: kernel/events/uprobes.c:1141 RCU-list traversed in non-reader section!! filter_chain register_for_each_vma uprobe_unregister_nosync __probe_event_disable Remove the incorrect lockdep condition since the rwsem provides sufficient protection for the list traversal. Fixes: cc01bd044e6a ("uprobes: travers uprobe's consumer list locklessly under SRCU protection") Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260128-uprobe_rcu-v2-1-994ea6d32730@debian.org
2026-01-16x86/uprobes: Fix XOL allocation failure for 32-bit tasksOleg Nesterov
This script #!/usr/bin/bash echo 0 > /proc/sys/kernel/randomize_va_space echo 'void main(void) {}' > TEST.c # -fcf-protection to ensure that the 1st endbr32 insn can't be emulated gcc -m32 -fcf-protection=branch TEST.c -o test bpftrace -e 'uprobe:./test:main {}' -c ./test "hangs", the probed ./test task enters an endless loop. The problem is that with randomize_va_space == 0 get_unmapped_area(TASK_SIZE - PAGE_SIZE) called by xol_add_vma() can not just return the "addr == TASK_SIZE - PAGE_SIZE" hint, this addr is used by the stack vma. arch_get_unmapped_area_topdown() doesn't take TIF_ADDR32 into account and in_32bit_syscall() is false, this leads to info.high_limit > TASK_SIZE. vm_unmapped_area() happily returns the high address > TASK_SIZE and then get_unmapped_area() returns -ENOMEM after the "if (addr > TASK_SIZE - len)" check. handle_swbp() doesn't report this failure (probably it should) and silently restarts the probed insn. Endless loop. I think that the right fix should change the x86 get_unmapped_area() paths to rely on TIF_ADDR32 rather than in_32bit_syscall(). Note also that if CONFIG_X86_X32_ABI=y, in_x32_syscall() falsely returns true in this case because ->orig_ax = -1. But we need a simple fix for -stable, so this patch just sets TS_COMPAT if the probed task is 32-bit to make in_ia32_syscall() true. Fixes: 1b028f784e8c ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()") Reported-by: Paulo Andrade <pandrade@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/aV5uldEvV7pb4RA8@redhat.com/ Cc: stable@vger.kernel.org Link: https://patch.msgid.link/aWO7Fdxn39piQnxu@redhat.com
2026-01-06uprobes: use kmap_local_page() for temporary page mappingsKeke Ming
Replace deprecated kmap_atomic() with kmap_local_page(). Signed-off-by: Keke Ming <ming.jvle@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://patch.msgid.link/20260103084243.195125-6-ming.jvle@gmail.com
2025-12-03perf/uprobes: Remove <space><Tab> whitespace noiseIngo Molnar
A few cases of space-Tab noise snuck in. Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/176478594889.498.15611228524880763978.tip-bot2@tip-bot2
2025-10-14uprobe: Move arch_uprobe_optimize right after handlers executionJiri Olsa
It's less confusing to optimize uprobe right after handlers execution and before we do the check for changed ip register to avoid situations where changed ip register would skip uprobe optimization. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com>
2025-10-02Merge tag 'mm-stable-2025-10-01-19-00' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 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() ...
2025-09-30Merge tag 'bpf-next-6.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Pull bpf updates from Alexei Starovoitov: - Support pulling non-linear xdp data with bpf_xdp_pull_data() kfunc (Amery Hung) Applied as a stable branch in bpf-next and net-next trees. - Support reading skb metadata via bpf_dynptr (Jakub Sitnicki) Also a stable branch in bpf-next and net-next trees. - Enforce expected_attach_type for tailcall compatibility (Daniel Borkmann) - Replace path-sensitive with path-insensitive live stack analysis in the verifier (Eduard Zingerman) This is a significant change in the verification logic. More details, motivation, long term plans are in the cover letter/merge commit. - Support signed BPF programs (KP Singh) This is another major feature that took years to materialize. Algorithm details are in the cover letter/marge commit - Add support for may_goto instruction to s390 JIT (Ilya Leoshkevich) - Add support for may_goto instruction to arm64 JIT (Puranjay Mohan) - Fix USDT SIB argument handling in libbpf (Jiawei Zhao) - Allow uprobe-bpf program to change context registers (Jiri Olsa) - Support signed loads from BPF arena (Kumar Kartikeya Dwivedi and Puranjay Mohan) - Allow access to union arguments in tracing programs (Leon Hwang) - Optimize rcu_read_lock() + migrate_disable() combination where it's used in BPF subsystem (Menglong Dong) - Introduce bpf_task_work_schedule*() kfuncs to schedule deferred execution of BPF callback in the context of a specific task using the kernel’s task_work infrastructure (Mykyta Yatsenko) - Enforce RCU protection for KF_RCU_PROTECTED kfuncs (Kumar Kartikeya Dwivedi) - Add stress test for rqspinlock in NMI (Kumar Kartikeya Dwivedi) - Improve the precision of tnum multiplier verifier operation (Nandakumar Edamana) - Use tnums to improve is_branch_taken() logic (Paul Chaignon) - Add support for atomic operations in arena in riscv JIT (Pu Lehui) - Report arena faults to BPF error stream (Puranjay Mohan) - Search for tracefs at /sys/kernel/tracing first in bpftool (Quentin Monnet) - Add bpf_strcasecmp() kfunc (Rong Tao) - Support lookup_and_delete_elem command in BPF_MAP_STACK_TRACE (Tao Chen) * tag 'bpf-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (197 commits) libbpf: Replace AF_ALG with open coded SHA-256 selftests/bpf: Add stress test for rqspinlock in NMI selftests/bpf: Add test case for different expected_attach_type bpf: Enforce expected_attach_type for tailcall compatibility bpftool: Remove duplicate string.h header bpf: Remove duplicate crypto/sha2.h header libbpf: Fix error when st-prefix_ops and ops from differ btf selftests/bpf: Test changing packet data from kfunc selftests/bpf: Add stacktrace map lookup_and_delete_elem test case selftests/bpf: Refactor stacktrace_map case with skeleton bpf: Add lookup_and_delete_elem for BPF_MAP_STACK_TRACE selftests/bpf: Fix flaky bpf_cookie selftest selftests/bpf: Test changing packet data from global functions with a kfunc bpf: Emit struct bpf_xdp_sock type in vmlinux BTF selftests/bpf: Task_work selftest cleanup fixes MAINTAINERS: Delete inactive maintainers from AF_XDP bpf: Mark kfuncs as __noclone selftests/bpf: Add kprobe multi write ctx attach test selftests/bpf: Add kprobe write ctx attach test selftests/bpf: Add uprobe context ip register change test ...
2025-09-30Merge tag 'perf-core-2025-09-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull performance events updates from Ingo Molnar: "Core perf code updates: - Convert mmap() related reference counts to refcount_t. This is in reaction to the recently fixed refcount bugs, which could have been detected earlier and could have mitigated the bug somewhat (Thomas Gleixner, Peter Zijlstra) - Clean up and simplify the callchain code, in preparation for sframes (Steven Rostedt, Josh Poimboeuf) Uprobes updates: - Add support to optimize usdt probes on x86-64, which gives a substantial speedup (Jiri Olsa) - Cleanups and fixes on x86 (Peter Zijlstra) PMU driver updates: - Various optimizations and fixes to the Intel PMU driver (Dapeng Mi) Misc cleanups and fixes: - Remove redundant __GFP_NOWARN (Qianfeng Rong)" * tag 'perf-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits) selftests/bpf: Fix uprobe_sigill test for uprobe syscall error value uprobes/x86: Return error from uprobe syscall when not called from trampoline perf: Skip user unwind if the task is a kernel thread perf: Simplify get_perf_callchain() user logic perf: Use current->flags & PF_KTHREAD|PF_USER_WORKER instead of current->mm == NULL perf: Have get_perf_callchain() return NULL if crosstask and user are set perf: Remove get_perf_callchain() init_nr argument perf/x86: Print PMU counters bitmap in x86_pmu_show_pmu_cap() perf/x86/intel: Add ICL_FIXED_0_ADAPTIVE bit into INTEL_FIXED_BITS_MASK perf/x86/intel: Change macro GLOBAL_CTRL_EN_PERF_METRICS to BIT_ULL(48) perf/x86: Add PERF_CAP_PEBS_TIMING_INFO flag perf/x86/intel: Fix IA32_PMC_x_CFG_B MSRs access error perf/x86/intel: Use early_initcall() to hook bts_init() uprobes: Remove redundant __GFP_NOWARN selftests/seccomp: validate uprobe syscall passes through seccomp seccomp: passthrough uprobe systemcall without filtering selftests/bpf: Fix uprobe syscall shadow stack test selftests/bpf: Change test_uretprobe_regs_change for uprobe and uretprobe selftests/bpf: Add uprobe_regs_equal test selftests/bpf: Add optimized usdt variant for basic usdt test ...
2025-09-29Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "There's good stuff across the board, including some nice mm improvements for CPUs with the 'noabort' BBML2 feature and a clever patch to allow ptdump to play nicely with block mappings in the vmalloc area. Confidential computing: - Add support for accepting secrets from firmware (e.g. ACPI CCEL) and mapping them with appropriate attributes. CPU features: - Advertise atomic floating-point instructions to userspace - Extend Spectre workarounds to cover additional Arm CPU variants - Extend list of CPUs that support break-before-make level 2 and guarantee not to generate TLB conflict aborts for changes of mapping granularity (BBML2_NOABORT) - Add GCS support to our uprobes implementation. Documentation: - Remove bogus SME documentation concerning register state when entering/exiting streaming mode. Entry code: - Switch over to the generic IRQ entry code (GENERIC_IRQ_ENTRY) - Micro-optimise syscall entry path with a compiler branch hint. Memory management: - Enable huge mappings in vmalloc space even when kernel page-table dumping is enabled - Tidy up the types used in our early MMU setup code - Rework rodata= for closer parity with the behaviour on x86 - For CPUs implementing BBML2_NOABORT, utilise block mappings in the linear map even when rodata= applies to virtual aliases - Don't re-allocate the virtual region between '_text' and '_stext', as doing so confused tools parsing /proc/vmcore. Miscellaneous: - Clean-up Kconfig menuconfig text for architecture features - Avoid redundant bitmap_empty() during determination of supported SME vector lengths - Re-enable warnings when building the 32-bit vDSO object - Avoid breaking our eggs at the wrong end. Perf and PMUs: - Support for v3 of the Hisilicon L3C PMU - Support for Hisilicon's MN and NoC PMUs - Support for Fujitsu's Uncore PMU - Support for SPE's extended event filtering feature - Preparatory work to enable data source filtering in SPE - Support for multiple lanes in the DWC PCIe PMU - Support for i.MX94 in the IMX DDR PMU driver - MAINTAINERS update (Thank you, Yicong) - Minor driver fixes (PERF_IDX2OFF() overflow, CMN register offsets). Selftests: - Add basic LSFE check to the existing hwcaps test - Support nolibc in GCS tests - Extend SVE ptrace test to pass unsupported regsets and invalid vector lengths - Minor cleanups (typos, cosmetic changes). System registers: - Fix ID_PFR1_EL1 definition - Fix incorrect signedness of some fields in ID_AA64MMFR4_EL1 - Sync TCR_EL1 definition with the latest Arm ARM (L.b) - Be stricter about the input fed into our AWK sysreg generator script - Typo fixes and removal of redundant definitions. ACPI, EFI and PSCI: - Decouple Arm's "Software Delegated Exception Interface" (SDEI) support from the ACPI GHES code so that it can be used by platforms booted with device-tree - Remove unnecessary per-CPU tracking of the FPSIMD state across EFI runtime calls - Fix a node refcount imbalance in the PSCI device-tree code. CPU Features: - Ensure register sanitisation is applied to fields in ID_AA64MMFR4 - Expose AIDR_EL1 to userspace via sysfs, primarily so that KVM guests can reliably query the underlying CPU types from the VMM - Re-enabling of SME support (CONFIG_ARM64_SME) as a result of fixes to our context-switching, signal handling and ptrace code" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (93 commits) arm64: cpufeature: Remove duplicate asm/mmu.h header arm64: Kconfig: Make CPU_BIG_ENDIAN depend on BROKEN perf/dwc_pcie: Fix use of uninitialized variable arm/syscalls: mark syscall invocation as likely in invoke_syscall Documentation: hisi-pmu: Add introduction to HiSilicon V3 PMU Documentation: hisi-pmu: Fix of minor format error drivers/perf: hisi: Add support for L3C PMU v3 drivers/perf: hisi: Refactor the event configuration of L3C PMU drivers/perf: hisi: Extend the field of tt_core drivers/perf: hisi: Extract the event filter check of L3C PMU drivers/perf: hisi: Simplify the probe process of each L3C PMU version drivers/perf: hisi: Export hisi_uncore_pmu_isr() drivers/perf: hisi: Relax the event ID check in the framework perf: Fujitsu: Add the Uncore PMU driver arm64: map [_text, _stext) virtual address range non-executable+read-only arm64/sysreg: Update TCR_EL1 register arm64: Enable vmalloc-huge with ptdump arm64: cpufeature: add Neoverse-V3AE to BBML2 allow list arm64: errata: Apply workarounds for Neoverse-V3AE arm64: cputype: Add Neoverse-V3AE definitions ...
2025-09-24uprobe: Do not emulate/sstep original instruction when ip is changedJiri Olsa
If uprobe handler changes instruction pointer we still execute single step) or emulate the original instruction and increment the (new) ip with its length. This makes the new instruction pointer bogus and application will likely crash on illegal instruction execution. If user decided to take execution elsewhere, it makes little sense to execute the original instruction, so let's skip it. Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20250916215301.664963-3-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-16uprobes: uprobe_warn should use passed taskJeremy Linton
uprobe_warn() is passed a task structure, yet its using current. For the most part this shouldn't matter, but since a task structure is provided, lets use it. Fixes: 248d3a7b2f10 ("uprobes: Change uprobe_copy_process() to dup return_instances") Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
2025-09-13mm: convert uprobes to mm_flags_*() accessorsLorenzo Stoakes
As part of the effort to move to mm->flags becoming a bitmap field, convert existing users to making use of the mm_flags_*() accessors which will, when the conversion is complete, be the only means of accessing mm_struct flags. No functional change intended. Link: https://lkml.kernel.org/r/1d4fe5963904cc0c707da1f53fbfe6471d3eff10.1755012943.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Ben Segall <bsegall@google.com> Cc: Borislav Betkov <bp@alien8.de> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dev Jain <dev.jain@arm.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kees Cook <kees@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Mariano Pache <npache@redhat.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Namhyung kim <namhyung@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-01copy_process: pass clone_flags as u64 across calltreeSimon Schuster
With the introduction of clone3 in commit 7f192e3cd316 ("fork: add clone3") the effective bit width of clone_flags on all architectures was increased from 32-bit to 64-bit, with a new type of u64 for the flags. However, for most consumers of clone_flags the interface was not changed from the previous type of unsigned long. While this works fine as long as none of the new 64-bit flag bits (CLONE_CLEAR_SIGHAND and CLONE_INTO_CGROUP) are evaluated, this is still undesirable in terms of the principle of least surprise. Thus, this commit fixes all relevant interfaces of callees to sys_clone3/copy_process (excluding the architecture-specific copy_thread) to consistently pass clone_flags as u64, so that no truncation to 32-bit integers occurs on 32-bit architectures. Signed-off-by: Simon Schuster <schuster.simon@siemens-energy.com> Link: https://lore.kernel.org/20250901-nios2-implement-clone3-v2-2-53fcf5577d57@siemens-energy.com Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-21uprobes: Remove redundant __GFP_NOWARNQianfeng Rong
Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made GFP_NOWAIT implicitly include __GFP_NOWARN. Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g., `GFP_NOWAIT | __GFP_NOWARN`) is now redundant. Let's clean up these redundant flags across subsystems. No functional changes. Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250805025000.346647-1-rongqianfeng@vivo.com
2025-08-21uprobes/x86: Add support to optimize uprobesJiri Olsa
Putting together all the previously added pieces to support optimized uprobes on top of 5-byte nop instruction. The current uprobe execution goes through following: - installs breakpoint instruction over original instruction - exception handler hit and calls related uprobe consumers - and either simulates original instruction or does out of line single step execution of it - returns to user space The optimized uprobe path does following: - checks the original instruction is 5-byte nop (plus other checks) - adds (or uses existing) user space trampoline with uprobe syscall - overwrites original instruction (5-byte nop) with call to user space trampoline - the user space trampoline executes uprobe syscall that calls related uprobe consumers - trampoline returns back to next instruction This approach won't speed up all uprobes as it's limited to using nop5 as original instruction, but we plan to use nop5 as USDT probe instruction (which currently uses single byte nop) and speed up the USDT probes. The arch_uprobe_optimize triggers the uprobe optimization and is called after first uprobe hit. I originally had it called on uprobe installation but then it clashed with elf loader, because the user space trampoline was added in a place where loader might need to put elf segments, so I decided to do it after first uprobe hit when loading is done. The uprobe is un-optimized in arch specific set_orig_insn call. The instruction overwrite is x86 arch specific and needs to go through 3 updates: (on top of nop5 instruction) - write int3 into 1st byte - write last 4 bytes of the call instruction - update the call instruction opcode And cleanup goes though similar reverse stages: - overwrite call opcode with breakpoint (int3) - write last 4 bytes of the nop5 instruction - write the nop5 first instruction byte We do not unmap and release uprobe trampoline when it's no longer needed, because there's no easy way to make sure none of the threads is still inside the trampoline. But we do not waste memory, because there's just single page for all the uprobe trampoline mappings. We do waste frame on page mapping for every 4GB by keeping the uprobe trampoline page mapped, but that seems ok. We take the benefit from the fact that set_swbp and set_orig_insn are called under mmap_write_lock(mm), so we can use the current instruction as the state the uprobe is in - nop5/breakpoint/call trampoline - and decide the needed action (optimize/un-optimize) based on that. Attaching the speed up from benchs/run_bench_uprobes.sh script: current: usermode-count : 152.604 ± 0.044M/s syscall-count : 13.359 ± 0.042M/s --> uprobe-nop : 3.229 ± 0.002M/s uprobe-push : 3.086 ± 0.004M/s uprobe-ret : 1.114 ± 0.004M/s uprobe-nop5 : 1.121 ± 0.005M/s uretprobe-nop : 2.145 ± 0.002M/s uretprobe-push : 2.070 ± 0.001M/s uretprobe-ret : 0.931 ± 0.001M/s uretprobe-nop5 : 0.957 ± 0.001M/s after the change: usermode-count : 152.448 ± 0.244M/s syscall-count : 14.321 ± 0.059M/s uprobe-nop : 3.148 ± 0.007M/s uprobe-push : 2.976 ± 0.004M/s uprobe-ret : 1.068 ± 0.003M/s --> uprobe-nop5 : 7.038 ± 0.007M/s uretprobe-nop : 2.109 ± 0.004M/s uretprobe-push : 2.035 ± 0.001M/s uretprobe-ret : 0.908 ± 0.001M/s uretprobe-nop5 : 3.377 ± 0.009M/s I see bit more speed up on Intel (above) compared to AMD. The big nop5 speed up is partly due to emulating nop5 and partly due to optimization. The key speed up we do this for is the USDT switch from nop to nop5: uprobe-nop : 3.148 ± 0.007M/s uprobe-nop5 : 7.038 ± 0.007M/s Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20250720112133.244369-11-jolsa@kernel.org
2025-08-21uprobes/x86: Add uprobe syscall to speed up uprobeJiri Olsa
Adding new uprobe syscall that calls uprobe handlers for given 'breakpoint' address. The idea is that the 'breakpoint' address calls the user space trampoline which executes the uprobe syscall. The syscall handler reads the return address of the initial call to retrieve the original 'breakpoint' address. With this address we find the related uprobe object and call its consumers. Adding the arch_uprobe_trampoline_mapping function that provides uprobe trampoline mapping. This mapping is backed with one global page initialized at __init time and shared by the all the mapping instances. We do not allow to execute uprobe syscall if the caller is not from uprobe trampoline mapping. The uprobe syscall ensures the consumer (bpf program) sees registers values in the state before the trampoline was called. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20250720112133.244369-10-jolsa@kernel.org
2025-08-21uprobes/x86: Add mapping for optimized uprobe trampolinesJiri Olsa
Adding support to add special mapping for user space trampoline with following functions: uprobe_trampoline_get - find or add uprobe_trampoline uprobe_trampoline_put - remove or destroy uprobe_trampoline The user space trampoline is exported as arch specific user space special mapping through tramp_mapping, which is initialized in following changes with new uprobe syscall. The uprobe trampoline needs to be callable/reachable from the probed address, so while searching for available address we use is_reachable_by_call function to decide if the uprobe trampoline is callable from the probe address. All uprobe_trampoline objects are stored in uprobes_state object and are cleaned up when the process mm_struct goes down. Adding new arch hooks for that, because this change is x86_64 specific. Locking is provided by callers in following changes. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20250720112133.244369-9-jolsa@kernel.org
2025-08-21uprobes: Add do_ref_ctr argument to uprobe_write functionJiri Olsa
Making update_ref_ctr call in uprobe_write conditional based on do_ref_ctr argument. This way we can use uprobe_write for instruction update without doing ref_ctr_offset update. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250720112133.244369-8-jolsa@kernel.org
2025-08-21uprobes: Add is_register argument to uprobe_write and uprobe_write_opcodeJiri Olsa
The uprobe_write has special path to restore the original page when we write original instruction back. This happens when uprobe_write detects that we want to write anything else but breakpoint instruction. Moving the detection away and passing it to uprobe_write as argument, so it's possible to write different instructions (other than just breakpoint and rest). Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250720112133.244369-7-jolsa@kernel.org
2025-08-21uprobes: Add nbytes argument to uprobe_writeJiri Olsa
Adding nbytes argument to uprobe_write and related functions as preparation for writing whole instructions in following changes. Also renaming opcode arguments to insn, which seems to fit better. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250720112133.244369-6-jolsa@kernel.org
2025-08-21uprobes: Add uprobe_write functionJiri Olsa
Adding uprobe_write function that does what uprobe_write_opcode did so far, but allows to pass verify callback function that checks the memory location before writing the opcode. It will be used in following changes to implement specific checking logic for instruction update. The uprobe_write_opcode now calls uprobe_write with verify_opcode as the verify callback. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250720112133.244369-5-jolsa@kernel.org
2025-08-21uprobes: Make copy_from_page globalJiri Olsa
Making copy_from_page global and adding uprobe prefix. Adding the uprobe prefix to copy_to_page as well for symmetry. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250720112133.244369-4-jolsa@kernel.org
2025-08-21uprobes: Rename arch_uretprobe_trampoline functionJiri Olsa
We are about to add uprobe trampoline, so cleaning up the namespace. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250720112133.244369-3-jolsa@kernel.org
2025-08-21uprobes: Remove breakpoint in unapply_uprobe under mmap_write_lockJiri Olsa
Currently unapply_uprobe takes mmap_read_lock, but it might call remove_breakpoint which eventually changes user pages. Current code writes either breakpoint or original instruction, so it can go away with read lock as explained in here [1]. But with the upcoming change that writes multiple instructions on the probed address we need to ensure that any update to mm's pages is exclusive. [1] https://lore.kernel.org/all/20240710140045.GA1084@redhat.com/ Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250720112133.244369-2-jolsa@kernel.org
2025-08-03Merge tag 'mm-nonmm-stable-2025-08-03-12-47' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: "Significant patch series in this pull request: - "squashfs: Remove page->mapping references" (Matthew Wilcox) gets us closer to being able to remove page->mapping - "relayfs: misc changes" (Jason Xing) does some maintenance and minor feature addition work in relayfs - "kdump: crashkernel reservation from CMA" (Jiri Bohac) switches us from static preallocation of the kdump crashkernel's working memory over to dynamic allocation. So the difficulty of a-priori estimation of the second kernel's needs is removed and the first kernel obtains extra memory - "generalize panic_print's dump function to be used by other kernel parts" (Feng Tang) implements some consolidation and rationalization of the various ways in which a failing kernel splats information at the operator * tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (80 commits) tools/getdelays: add backward compatibility for taskstats version kho: add test for kexec handover delaytop: enhance error logging and add PSI feature description samples: Kconfig: fix spelling mistake "instancess" -> "instances" fat: fix too many log in fat_chain_add() scripts/spelling.txt: add notifer||notifier to spelling.txt xen/xenbus: fix typo "notifer" net: mvneta: fix typo "notifer" drm/xe: fix typo "notifer" cxl: mce: fix typo "notifer" KVM: x86: fix typo "notifer" MAINTAINERS: add maintainers for delaytop ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below() ucount: fix atomic_long_inc_below() argument type kexec: enable CMA based contiguous allocation stackdepot: make max number of pools boot-time configurable lib/xxhash: remove unused functions init/Kconfig: restore CONFIG_BROKEN help text lib/raid6: update recov_rvv.c zero page usage docs: update docs after introducing delaytop ...
2025-07-09uprobes: revert ref_ctr_offset in uprobe_unregister error pathJiri Olsa
There's error path that could lead to inactive uprobe: 1) uprobe_register succeeds - updates instruction to int3 and changes ref_ctr from 0 to 1 2) uprobe_unregister fails - int3 stays in place, but ref_ctr is changed to 0 (it's not restored to 1 in the fail path) uprobe is leaked 3) another uprobe_register comes and re-uses the leaked uprobe and succeds - but int3 is already in place, so ref_ctr update is skipped and it stays 0 - uprobe CAN NOT be triggered now 4) uprobe_unregister fails because ref_ctr value is unexpected Fix this by reverting the updated ref_ctr value back to 1 in step 2), which is the case when uprobe_unregister fails (int3 stays in place), but we have already updated refctr. The new scenario will go as follows: 1) uprobe_register succeeds - updates instruction to int3 and changes ref_ctr from 0 to 1 2) uprobe_unregister fails - int3 stays in place and ref_ctr is reverted to 1.. uprobe is leaked 3) another uprobe_register comes and re-uses the leaked uprobe and succeds - but int3 is already in place, so ref_ctr update is skipped and it stays 1 - uprobe CAN be triggered now 4) uprobe_unregister succeeds Link: https://lkml.kernel.org/r/20250514101809.2010193-1-jolsa@kernel.org Fixes: 1cc33161a83d ("uprobes: Support SDT markers having reference count (semaphore)") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Suggested-by: Oleg Nesterov <oleg@redhat.com> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09mm: filter zone device pages returned from folio_walk_start()Alistair Popple
Previously dax pages were skipped by the pagewalk code as pud_special() or vm_normal_page{_pmd}() would be false for DAX pages. Now that dax pages are refcounted normally that is no longer the case, so the pagewalk code will start returning them. Most callers already explicitly filter for DAX or zone device pages so don't need updating. However some don't, so add checks to those callers. Link: https://lkml.kernel.org/r/4ecb7b357fc5b435588024770b88bbb695c30090.1750323463.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Cc: Balbir Singh <balbirs@nvidia.com> Cc: Björn Töpel <bjorn@kernel.org> Cc: Björn Töpel <bjorn@rivosinc.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chunyan Zhang <zhang.lyra@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Inki Dae <m.szyprowski@samsung.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: John Groves <john@groves.net> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09mm: use folio_expected_ref_count() helper for reference countingShivank Garg
Replace open-coded folio reference count calculations with the folio_expected_ref_count(). No functional changes intended. Link: https://lkml.kernel.org/r/20250611052706.515408-2-shivankg@amd.com Signed-off-by: Shivank Garg <shivankg@amd.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Marc Rutland <mark.rutland@arm.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Namhyung kim <namhyung@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11kernel/events/uprobes: uprobe_write_opcode() rewriteDavid Hildenbrand
uprobe_write_opcode() does some pretty low-level things that really, it shouldn't be doing: for example, manually breaking COW by allocating anonymous folios and replacing mapped pages. Further, it does seem to do some shaky things: for example, writing to possible COW-shared anonymous pages or zapping anonymous pages that might be pinned. We're also not taking care of uffd, uffd-wp, softdirty ... although rather corner cases here. Let's just get it right like ordinary ptrace writes would. Let's rewrite the code, leaving COW-breaking to core-MM, triggered by FOLL_FORCE|FOLL_WRITE (note that the code was already using FOLL_FORCE). We'll use GUP to lookup/faultin the page and break COW if required. Then, we'll walk the page tables using a folio_walk to perform our page modification atomically by temporarily unmap the PTE + flushing the TLB. Likely, we could avoid the temporary unmap in case we can just atomically write the instruction, but that will be a separate project. Unfortunately, we still have to implement the zapping logic manually, because we only want to zap in specific circumstances (e.g., page content identical). Note that we can now handle large folios (compound pages) and the shared zeropage just fine, so drop these checks. Link: https://lkml.kernel.org/r/20250321113713.204682-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <olsajiri@gmail.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Namhyung kim <namhyung@kernel.org> Cc: Russel King <linux@armlinux.org.uk> Cc: tongtiangen <tongtiangen@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11kernel/events/uprobes: pass VMA to set_swbp(), set_orig_insn() and ↵David Hildenbrand
uprobe_write_opcode() We already have the VMA, no need to look it up using get_user_page_vma_remote(). We can now switch to get_user_pages_remote(). Link: https://lkml.kernel.org/r/20250321113713.204682-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <olsajiri@gmail.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Namhyung kim <namhyung@kernel.org> Cc: Russel King <linux@armlinux.org.uk> Cc: tongtiangen <tongtiangen@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11kernel/events/uprobes: pass VMA instead of MM to remove_breakpoint()David Hildenbrand
Patch series "kernel/events/uprobes: uprobe_write_opcode() rewrite", v3. Currently, uprobe_write_opcode() implements COW-breaking manually, which is really far from ideal. Further, there is interest in supporting uprobes on hugetlb pages [1], and leaving at least the COW-breaking to the core will make this much easier. Also, I think the current code doesn't really handle some things properly (see patch #3) when replacing/zapping pages. Let's rewrite it, to leave COW-breaking to the fault handler, and handle registration/unregistration by temporarily unmapping the anonymous page, modifying it, and mapping it again. We still have to implement zapping of anonymous pages ourselves, unfortunately. We could look into not performing the temporary unmapping if we can perform the write atomically, which would likely also make adding hugetlb support a lot easier. But, limited (e.g., only PMD/PUD) hugetlb support could be added on top of this with some tweaking. Note that we now won't have to allocate another anonymous folio when unregistering (which will be beneficial for hugetlb as well), we can simply modify the already-mapped one from the registration (if any). When registering a uprobe, we'll first trigger a ptrace-like write fault to break COW, to then modify the already-mapped page. Briefly sanity tested with perf probes and with the bpf uprobes selftest. This patch (of 3): Pass VMA instead of MM to remove_breakpoint() and remove the "MM" argument from install_breakpoint(), because it can easily be derived from the VMA. Link: https://lkml.kernel.org/r/20250321113713.204682-1-david@redhat.com Link: https://lkml.kernel.org/r/20250321113713.204682-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Jiri Olsa <olsajiri@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Namhyung kim <namhyung@kernel.org> Cc: Russel King <linux@armlinux.org.uk> Cc: tongtiangen <tongtiangen@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-04-07uprobes: Avoid false-positive lockdep splat on CONFIG_PREEMPT_RT=y in the ↵Andrii Nakryiko
ri_timer() uprobe timer callback, use raw_write_seqcount_*() Avoid a false-positive lockdep warning in the CONFIG_PREEMPT_RT=y configuration when using write_seqcount_begin() in the uprobe timer callback by using raw_write_* APIs. Uprobe's use of timer callback is guaranteed to not race with itself for a given uprobe_task, and as such seqcount's insistence on having preemption disabled on the writer side is irrelevant. So switch to raw_ variants of seqcount API instead of disabling preemption unnecessarily. Also, point out in the comments more explicitly why we use seqcount despite our reader side being rather simple and never retrying. We favor well-maintained kernel primitive in favor of open-coding our own memory barriers. Fixes: 8622e45b5da1 ("uprobes: Reuse return_instances between multiple uretprobes within task") Reported-by: Alexei Starovoitov <ast@kernel.org> Suggested-by: Sebastian Siewior <bigeasy@linutronix.de> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@kernel.org Link: https://lore.kernel.org/r/20250404194848.2109539-1-andrii@kernel.org
2025-04-01mseal sysmap: uprobe mappingJeff Xu
Provide support to mseal the uprobe mapping. Unlike other system mappings, the uprobe mapping is not established during program startup. However, its lifetime is the same as the process's lifetime. It could be sealed from creation. Test was done with perf tool, and observe the uprobe mapping is sealed. Link: https://lkml.kernel.org/r/20250305021711.3867874-6-jeffxu@google.com Signed-off-by: Jeff Xu <jeffxu@chromium.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Kees Cook <kees@kernel.org> Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org> Cc: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrei Vagin <avagin@gmail.com> Cc: Anna-Maria Behnsen <anna-maria@linutronix.de> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Benjamin Berg <benjamin@sipsolutions.net> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: Elliot Hughes <enh@google.com> Cc: Florian Faineli <f.fainelli@gmail.com> Cc: Greg Ungerer <gerg@kernel.org> Cc: Guenter Roeck <groeck@chromium.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Jason A. Donenfeld <jason@zx2c4.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Jorge Lucangeli Obes <jorgelo@chromium.org> Cc: Linus Waleij <linus.walleij@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcow (Oracle) <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Mike Rapoport <mike.rapoport@gmail.com> Cc: Pedro Falcato <pedro.falcato@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Stephen Röttger <sroettger@google.com> Cc: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-04-01Merge tag 'mm-stable-2025-03-30-16-52' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - The series "Enable strict percpu address space checks" from Uros Bizjak uses x86 named address space qualifiers to provide compile-time checking of percpu area accesses. This has caused a small amount of fallout - two or three issues were reported. In all cases the calling code was found to be incorrect. - The series "Some cleanup for memcg" from Chen Ridong implements some relatively monir cleanups for the memcontrol code. - The series "mm: fixes for device-exclusive entries (hmm)" from David Hildenbrand fixes a boatload of issues which David found then using device-exclusive PTE entries when THP is enabled. More work is needed, but this makes thins better - our own HMM selftests now succeed. - The series "mm: zswap: remove z3fold and zbud" from Yosry Ahmed remove the z3fold and zbud implementations. They have been deprecated for half a year and nobody has complained. - The series "mm: further simplify VMA merge operation" from Lorenzo Stoakes implements numerous simplifications in this area. No runtime effects are anticipated. - The series "mm/madvise: remove redundant mmap_lock operations from process_madvise()" from SeongJae Park rationalizes the locking in the madvise() implementation. Performance gains of 20-25% were observed in one MADV_DONTNEED microbenchmark. - The series "Tiny cleanup and improvements about SWAP code" from Baoquan He contains a number of touchups to issues which Baoquan noticed when working on the swap code. - The series "mm: kmemleak: Usability improvements" from Catalin Marinas implements a couple of improvements to the kmemleak user-visible output. - The series "mm/damon/paddr: fix large folios access and schemes handling" from Usama Arif provides a couple of fixes for DAMON's handling of large folios. - The series "mm/damon/core: fix wrong and/or useless damos_walk() behaviors" from SeongJae Park fixes a few issues with the accuracy of kdamond's walking of DAMON regions. - The series "expose mapping wrprotect, fix fb_defio use" from Lorenzo Stoakes changes the interaction between framebuffer deferred-io and core MM. No functional changes are anticipated - this is preparatory work for the future removal of page structure fields. - The series "mm/damon: add support for hugepage_size DAMOS filter" from Usama Arif adds a DAMOS filter which permits the filtering by huge page sizes. - The series "mm: permit guard regions for file-backed/shmem mappings" from Lorenzo Stoakes extends the guard region feature from its present "anon mappings only" state. The feature now covers shmem and file-backed mappings. - The series "mm: batched unmap lazyfree large folios during reclamation" from Barry Song cleans up and speeds up the unmapping for pte-mapped large folios. - The series "reimplement per-vma lock as a refcount" from Suren Baghdasaryan puts the vm_lock back into the vma. Our reasons for pulling it out were largely bogus and that change made the code more messy. This patchset provides small (0-10%) improvements on one microbenchmark. - The series "Docs/mm/damon: misc DAMOS filters documentation fixes and improves" from SeongJae Park does some maintenance work on the DAMON docs. - The series "hugetlb/CMA improvements for large systems" from Frank van der Linden addresses a pile of issues which have been observed when using CMA on large machines. - The series "mm/damon: introduce DAMOS filter type for unmapped pages" from SeongJae Park enables users of DMAON/DAMOS to filter my the page's mapped/unmapped status. - The series "zsmalloc/zram: there be preemption" from Sergey Senozhatsky teaches zram to run its compression and decompression operations preemptibly. - The series "selftests/mm: Some cleanups from trying to run them" from Brendan Jackman fixes a pile of unrelated issues which Brendan encountered while runnimg our selftests. - The series "fs/proc/task_mmu: add guard region bit to pagemap" from Lorenzo Stoakes permits userspace to use /proc/pid/pagemap to determine whether a particular page is a guard page. - The series "mm, swap: remove swap slot cache" from Kairui Song removes the swap slot cache from the allocation path - it simply wasn't being effective. - The series "mm: cleanups for device-exclusive entries (hmm)" from David Hildenbrand implements a number of unrelated cleanups in this code. - The series "mm: Rework generic PTDUMP configs" from Anshuman Khandual implements a number of preparatoty cleanups to the GENERIC_PTDUMP Kconfig logic. - The series "mm/damon: auto-tune aggregation interval" from SeongJae Park implements a feedback-driven automatic tuning feature for DAMON's aggregation interval tuning. - The series "Fix lazy mmu mode" from Ryan Roberts fixes some issues in powerpc, sparc and x86 lazy MMU implementations. Ryan did this in preparation for implementing lazy mmu mode for arm64 to optimize vmalloc. - The series "mm/page_alloc: Some clarifications for migratetype fallback" from Brendan Jackman reworks some commentary to make the code easier to follow. - The series "page_counter cleanup and size reduction" from Shakeel Butt cleans up the page_counter code and fixes a size increase which we accidentally added late last year. - The series "Add a command line option that enables control of how many threads should be used to allocate huge pages" from Thomas Prescher does that. It allows the careful operator to significantly reduce boot time by tuning the parallalization of huge page initialization. - The series "Fix calculations in trace_balance_dirty_pages() for cgwb" from Tang Yizhou fixes the tracing output from the dirty page balancing code. - The series "mm/damon: make allow filters after reject filters useful and intuitive" from SeongJae Park improves the handling of allow and reject filters. Behaviour is made more consistent and the documention is updated accordingly. - The series "Switch zswap to object read/write APIs" from Yosry Ahmed updates zswap to the new object read/write APIs and thus permits the removal of some legacy code from zpool and zsmalloc. - The series "Some trivial cleanups for shmem" from Baolin Wang does as it claims. - The series "fs/dax: Fix ZONE_DEVICE page reference counts" from Alistair Popple regularizes the weird ZONE_DEVICE page refcount handling in DAX, permittig the removal of a number of special-case checks. - The series "refactor mremap and fix bug" from Lorenzo Stoakes is a preparatoty refactoring and cleanup of the mremap() code. - The series "mm: MM owner tracking for large folios (!hugetlb) + CONFIG_NO_PAGE_MAPCOUNT" from David Hildenbrand reworks the manner in which we determine whether a large folio is known to be mapped exclusively into a single MM. - The series "mm/damon: add sysfs dirs for managing DAMOS filters based on handling layers" from SeongJae Park adds a couple of new sysfs directories to ease the management of DAMON/DAMOS filters. - The series "arch, mm: reduce code duplication in mem_init()" from Mike Rapoport consolidates many per-arch implementations of mem_init() into code generic code, where that is practical. - The series "mm/damon/sysfs: commit parameters online via damon_call()" from SeongJae Park continues the cleaning up of sysfs access to DAMON internal data. - The series "mm: page_ext: Introduce new iteration API" from Luiz Capitulino reworks the page_ext initialization to fix a boot-time crash which was observed with an unusual combination of compile and cmdline options. - The series "Buddy allocator like (or non-uniform) folio split" from Zi Yan reworks the code to split a folio into smaller folios. The main benefit is lessened memory consumption: fewer post-split folios are generated. - The series "Minimize xa_node allocation during xarry split" from Zi Yan reduces the number of xarray xa_nodes which are generated during an xarray split. - The series "drivers/base/memory: Two cleanups" from Gavin Shan performs some maintenance work on the drivers/base/memory code. - The series "Add tracepoints for lowmem reserves, watermarks and totalreserve_pages" from Martin Liu adds some more tracepoints to the page allocator code. - The series "mm/madvise: cleanup requests validations and classifications" from SeongJae Park cleans up some warts which SeongJae observed during his earlier madvise work. - The series "mm/hwpoison: Fix regressions in memory failure handling" from Shuai Xue addresses two quite serious regressions which Shuai has observed in the memory-failure implementation. - The series "mm: reliable huge page allocator" from Johannes Weiner makes huge page allocations cheaper and more reliable by reducing fragmentation. - The series "Minor memcg cleanups & prep for memdescs" from Matthew Wilcox is preparatory work for the future implementation of memdescs. - The series "track memory used by balloon drivers" from Nico Pache introduces a way to track memory used by our various balloon drivers. - The series "mm/damon: introduce DAMOS filter type for active pages" from Nhat Pham permits users to filter for active/inactive pages, separately for file and anon pages. - The series "Adding Proactive Memory Reclaim Statistics" from Hao Jia separates the proactive reclaim statistics from the direct reclaim statistics. - The series "mm/vmscan: don't try to reclaim hwpoison folio" from Jinjiang Tu fixes our handling of hwpoisoned pages within the reclaim code. * tag 'mm-stable-2025-03-30-16-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (431 commits) mm/page_alloc: remove unnecessary __maybe_unused in order_to_pindex() x86/mm: restore early initialization of high_memory for 32-bits mm/vmscan: don't try to reclaim hwpoison folio mm/hwpoison: introduce folio_contain_hwpoisoned_page() helper cgroup: docs: add pswpin and pswpout items in cgroup v2 doc mm: vmscan: split proactive reclaim statistics from direct reclaim statistics selftests/mm: speed up split_huge_page_test selftests/mm: uffd-unit-tests support for hugepages > 2M docs/mm/damon/design: document active DAMOS filter type mm/damon: implement a new DAMOS filter type for active pages fs/dax: don't disassociate zero page entries MM documentation: add "Unaccepted" meminfo entry selftests/mm: add commentary about 9pfs bugs fork: use __vmalloc_node() for stack allocation docs/mm: Physical Memory: Populate the "Zones" section xen: balloon: update the NR_BALLOON_PAGES state hv_balloon: update the NR_BALLOON_PAGES state balloon_compaction: update the NR_BALLOON_PAGES state meminfo: add a per node counter for balloon drivers mm: remove references to folio in __memcg_kmem_uncharge_page() ...