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2026-10-01perf: Require kernel access for text poke eventsZhengchuan Liang1-1/+1
Perf events with exclude_kernel=1 can be opened without kernel perf access. However, exclude_kernel does not suppress text-poke sideband records. Every PERF_RECORD_TEXT_POKE is marked PERF_RECORD_MISC_KERNEL and contains a raw kernel instruction address. An unprivileged task can therefore open and mmap a task-local software event with text_poke=1. Both opening a count-only tracepoint event and configuring UDP GRO for ESP-in-UDP cause updates to inline static calls; the observer receives the relocated addresses of the modified instructions. For a known kernel image, any such address reveals the runtime kernel text base despite KASLR. Call perf_allow_kernel() whenever attr.text_poke is set, regardless of exclude_kernel. Events that neither monitor kernel execution nor request text-poke records retain their existing permissions. Fixes: e17d43b93e54 ("perf: Add perf text poke event") Assisted-by: LLM Signed-off-by: Zhengchuan Liang <zcliangcn@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/99131354c41e23188f778b92f90363775b482395.1790573390.git.zcliangcn@gmail.com
2026-10-01perf: Replace perf_event_header__init_id with full header initIan Rogers2-182/+132
perf_iterate_sb() invokes its callback for each matching perf_event on the CPU and task context, passing a shared caller-allocated event structure. perf_event_header__init_id() mutated header->size in place by adding event->id_header_size, requiring sideband output callbacks to save and restore header fields across iterations. Three sideband callbacks failed to save and restore header.size around perf_event_header__init_id(): - perf_event_ksymbol_output() - perf_event_bpf_output() - perf_event_text_poke_output() When multiple events with attr.ksymbol, attr.bpf_event, or attr.text_poke and sample_id_all are active on the same CPU, each subsequent event receives a record whose header.size is inflated by all preceding events' id_header_size values while only a single id_sample is written, leaving uninitialized ring-buffer bytes at the end of the record and causing userspace perf to fail with -EFAULT ("Bad address") when parsing the sample_id trailer. Similarly, perf_event_mmap_output() set PERF_RECORD_MISC_MMAP_BUILD_ID in mmap_event->event_id.header.misc when event->attr.build_id was enabled, but only saved and restored header.size and header.type. If an event with attr.build_id was followed by an event with attr.mmap2 and !attr.build_id, the second event received PERF_RECORD_MISC_MMAP_BUILD_ID in header.misc while its payload contained maj/min/ino/ino_generation instead of a build ID. Rather than splitting header initialization between callers and output callbacks and saving/restoring mutated header fields, replace perf_event_header__init_id() with perf_event_header__init(), which initializes header->type, header->misc, and header->size alongside the sample_id fields on each invocation. Fixes: 76193a94522f ("perf, bpf: Introduce PERF_RECORD_KSYMBOL") Fixes: 6ee52e2a3fe4 ("perf, bpf: Introduce PERF_RECORD_BPF_EVENT") Fixes: e17d43b93e54 ("perf: Add perf text poke event") Fixes: 88a16a130933 ("perf: Add build id data in mmap2 event") Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260929222332.973435-1-irogers@google.com Cc: stable@vger.kernel.org
2026-10-01perf: Fix race between perf_event_exit_task() and perf_pending_task()Luo Gengkun1-2/+4
A race condition exists between perf_event_exit_task() and perf_pending_task() during begin_new_exec(). During begin_new_exec(), perf_event_exit_task() may be called, and the PF_EXITING flag is not set on task. So perf_sigtrap() continues to execute and triggers WARN_ON_ONCE(event->ctx->task != current). Since both task exit and exec paths can call perf_event_exit_task() which sets ctx->task to TASK_TOMBSTONE, fix this by explicitly checking if event->ctx->task equals TASK_TOMBSTONE and dropping the redundant PF_EXITING check. Fixes: 97ba62b27867 ("perf: Add support for SIGTRAP on perf events") Signed-off-by: Luo Gengkun <luogengkun2@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260920075026.990582-1-luogengkun2@huawei.com
2026-09-23perf/core: Run sched_task() for PMUs with only CPU-wide eventsPuranjay Mohan1-4/+9
perf_pmu_sched_task() returns early when cpuctx->task_ctx is set and leaves the work to perf_ctx_sched_task_cb(), which only walks ctx->pmu_ctx_list. A PMU whose events are all CPU-wide is not on that list, so nothing calls its sched_task(). With perf record -b -e cycles -a -- ls armv8pmu_sched_task() is skipped on every switch to a task that has a perf context but no event on that PMU, and BRBE records leak across the task boundary. intel_pmu_lbr_add() calls perf_sched_cb_inc() unconditionally too, so LBR records leak the same way on x86. Drop the early return and skip only the CPCs that perf_ctx_sched_task_cb() handles. That one needs a gate of its own to make the split exact: it tests cpc->sched_cb_usage, which perf_sched_cb_inc() sets per CPU for every branch stack user, so a task with an event for that PMU pinned to another CPU would be handled twice. On x86 the second __intel_pmu_lbr_restore() finds lbr_stack_state == LBR_NONE and calls intel_pmu_lbr_reset(), throwing away the callstack the first one restored. cpc->task_epc is set only while a task context is scheduled in, and there is one epc per PMU on ctx->pmu_ctx_list, so the two gates are inverses. For the CPCs perf_pmu_sched_task() picks up, the callback now runs outside the perf_ctx_disable() and perf_ctx_enable() pair in perf_event_context_sched_in(). __perf_pmu_sched_task() disables the PMU around the call itself. Fixes: bd2756811766 ("perf: Rewrite core context handling") Signed-off-by: Puranjay Mohan <puranjay@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Yifan Wu <wuyifan50@huawei.com> Link: https://patch.msgid.link/20260810133540.1947118-3-puranjay@kernel.org Cc: stable@vger.kernel.org
2026-09-23perf/core: Fix NULL pmu_ctx passed to pmu->sched_task()Puranjay Mohan1-1/+1
perf_pmu_sched_task() returns early when cpuctx->task_ctx is set, and cpc->task_epc is only non-NULL while a task context is scheduled in on this CPU. __perf_pmu_sched_task() therefore always passes NULL: Unable to handle kernel NULL pointer dereference at virtual address 00 pc : armv8pmu_sched_task+0x14/0x50 Call trace: armv8pmu_sched_task+0x14/0x50 (P) perf_pmu_sched_task+0xac/0x108 __perf_event_task_sched_out+0x6c/0xe0 Pass &cpc->epc instead, the CPU-wide context for this PMU, which the function already dereferences a few lines up to find pmu. armv8pmu_sched_task() is the only in-tree implementation that dereferences the argument, and it only reads ->pmu, so the oops needs BRBE, added in v6.17. Fixes: bd2756811766 ("perf: Rewrite core context handling") Signed-off-by: Puranjay Mohan <puranjay@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Yifan Wu <wuyifan50@huawei.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260810133540.1947118-2-puranjay@kernel.org
2026-09-23perf/core: Fix a refcount leak in attach_perf_ctx_data()Namhyung Kim1-0/+2
The attach_perf_ctx_data() can race on global and !global cases. The global case is protected by global_ctx_data_rwsem and shares a single reference count using perf_ctx_data.global field. But when it races with !global case, it may miss to set the global field and result in a reference count leak. CPU1 CPU2 ---------------------------------------------------------------- attach_task_ctx_data(.global=1) attach_task_ctx_data(.global=0) cd1 = alloc_perf_ctx_data(); cd2 = alloc_perf_ctx_data(); // { .global = 0, .refcount = 1 }; try_cmpxchg(); // success, // task->perf_ctx_data = cd2 try_cmpxhg(); // fail; old = cd2 refcount_inc_not_zero(&old->refcount); // success // old.refcount = 2 free_perf_ctx_data(cd1); Then later detach_global_ctx_data() will see the data but it's not marked as global, so it won't call detach_task_ctx_data(). Fixes: 506e64e710ff ("perf: attach/detach PMU specific data") Assisted-by: Sashiko.dev:Gemini-3.1-pro Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260920231639.11910-1-namhyung@kernel.org
2026-09-18perf: Fix null pointer access in is_include_guest_event()Vinay Belgaumkar1-0/+4
A typical module unload occurring event when there is an active perf connection leads to freeing of the pmu pointer. The call log is something like: .. __pmu_detach_event pmu_detach_event pmu_detach_events perf_pmu_unregister .. __pmu_detach_event() sets event->pmu to null. When the perf connection finally is closed, the following stack trace is observed: Oops: general protection fault, kernel NULL pointer dereference ... RIP: 0010:_free_event+0x3e/0x370 ... Call Trace: ... perf_event_release_kernel+0x260/0x2d0 perf_release+0x12/0x20 A call to mediated_pmu_unaccount_event() inside _free_event() is the root cause of this crash. Adding a check inside is_include_guest_event() ensures we don't accidentally access a null pmu ptr. In addition to this, we will now call mediated_pmu_unaccount_event() before clearing the pmu ptr so that nr_include_guest_events counts are maintained correctly. Fixes: eff95e170275 ("perf: Add APIs to create/release mediated guest vPMUs") Assisted-by: Claude:Claude-Sonnet-5 Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Link: https://patch.msgid.link/20260904181625.1394082-1-vinay.belgaumkar@intel.com
2026-09-10perf/core: Allow list_del during perf_event_overflow()Thomas Richter1-2/+2
A PMU might use perf_sched_cb_inc() and perf_sched_cb_dec() interface to get the PMU call back function pmu::sched_task invoked at schedule in and schedule out. This is achieved by walking along the list anchored by sched_cb_list. The following scenario might lead to a list corruption. perf_pmu_sched_task() for_each_list_entry(..., &sched_cb_list) +--> __perf_pmu_sched_task() +--> event->pmu->sched_task()) +--> PMU_push_sample() +--> perf_event_overflow() +--> __perf_event_overflow() +--> pmu->stop() +--> perf_sched_cb_dec() remove entry from sched_cb_list while list node in use. This happens when ioctl(fd, PERF_EVENT_IOC_REFRESH, xxx) has been invoked and perf_event::event_limit hits zero. Prevent the list corruption and convert for_each_list_entry() to for_each_list_entry_safe(). Fixes: bd2756811766 ("perf: Rewrite core context handling") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260908105637.627004-1-tmricht@linux.ibm.com
2026-09-06Merge tag 'perf-urgent-2026-09-06' of ↵Linus Torvalds2-12/+17
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf events fixes from Ingo Molnar: - Skip empty AUX records with only format flags (Leo Yan) - Fix use-after-free when perf mmap() revival races with the last munmap() (Yilin Zhang, Weiming Shi) * tag 'perf-urgent-2026-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Fix use-after-free when perf mmap() revival races with the last munmap() perf/core: Skip empty AUX records with only format flags
2026-09-04treewide: refresh kmalloc_obj() conversionsKees Cook1-3/+2
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-09-02perf: Fix use-after-free when perf mmap() revival races with the last munmap()Yilin Zhang1-10/+10
perf_mmap_close() drops rb->mmap_count *without* holding event->mmap_mutex (the refcount_dec_and_test() right before the refcount_dec_and_mutex_lock() of event->mmap_count). A concurrent perf_mmap_rb() can slot its entire "revival" path into that window (perf_mmap holds event->mmap_mutex for its whole duration, including rb_alloc): munmap side (perf_mmap_close) mmap side (perf_mmap_rb) ----------------------------------- -------------------------------- rb->mmap_count 1 -> 0 (no lock) (holds event->mmap_mutex) inc_not_zero(rb->mmap_count) fails ring_buffer_attach(event, NULL) rb_alloc() + attach new rb refcount_set(&event->mmap_count, 1) lock; event->mmap_count 1 -> 0 ring_buffer_attach(event, NULL) ring_buffer_put() -> frees the *new* rb The revival's refcount_set(&event->mmap_count, 1) is an invisible 1 -> 1 write: the close frees the just-revived buffer although the other process still has it mapped -- a page-level use-after-free allowing local privilege escalation to root by any unprivileged user (default kernel.perf_event_paranoid=2). Swap the order of the two counter updates: event->mmap_count is dropped first via refcount_dec_and_mutex_lock(), so its 1 -> 0 transition and the ring_buffer_attach() stay serialized with perf_mmap(). rb->mmap_count == 0 then implies every event using the buffer is detached already, so the result of the rb->mmap_count drop can gate the remaining teardown directly and detach_rest is no longer needed. An earlier fix for this race from Kyle Zeng and David Lee takes event->mmap_mutex around both counter updates [0]; here the not-last close stays lockless. Fixes: 59741451b49c ("perf: Identify the 0->1 transition for event::mmap_count") Reported-by: Kimi Security Team <bug-report@moonshot.ai> Suggested-by: Peter Zijlstra <peterz@infradead.org> Co-developed-by: Weiming Shi <shiweiming@moonshot.ai> Signed-off-by: Weiming Shi <shiweiming@moonshot.ai> Signed-off-by: Yilin Zhang <yilinzhang@moonshot.ai> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/linux-perf-users/20260804060931.711308-1-david.lee@trailofbits.com/ [0] Cc: <stable@vger.kernel.org> Cc: stable@vger.kernel.org # 6.18+ Link: https://patch.msgid.link/20260831162155.1437652-1-yilinzhang@moonshot.ai
2026-09-02perf/core: Skip empty AUX records with only format flagsLeo Yan1-2/+7
perf_aux_output_end() emits a PERF_RECORD_AUX when the recorded size is nonzero or when any flag other than PERF_AUX_FLAG_OVERWRITE is set. PMU format flags describe how an AUX payload is encoded. TRBE driver sets PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW for raw trace buffers, causing an AUX record to be emitted even when no trace data. This is noticeable when tracing a task with strace. Ptrace stops repeatedly end empty AUX transactions, producing many zero-sized PERF_RECORD_AUX records. For example: perf record -e cs_etm//u -m,128M -- strace ls perf script -D 2>&1 | awk '/PERF_RECORD_AUX offset/ { for (i = 1; i <= NF; i++) if ($i == "size:" && $(i + 1) == "0") count++ } END { print count }' 165 This recording contains 165 zero-sized AUX records which provide no useful information to userspace. Ignore PERF_AUX_FLAG_PMU_FORMAT_TYPE_MASK, together with PERF_AUX_FLAG_OVERWRITE, when deciding whether an empty AUX record is useful. Zero-sized records carrying TRUNCATED, PARTIAL or COLLISION are still emitted. Fixes: 547b60988e63 ("perf: aux: Add flags for the buffer format") Reported-by: Tamas Petz <tamas.petz@arm.com> Signed-off-by: Leo Yan <leo.yan@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260825-perf_core_fix_zero_aux_records-v1-1-23b95e8d5df3@arm.com
2026-08-27Merge tag 'mm-stable-2026-08-26-15-22' of ↵Linus Torvalds1-1/+1
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)1-1/+1
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>
2026-08-21Merge tag 'drm-next-2026-08-20' of https://gitlab.freedesktop.org/drm/kernelLinus Torvalds1-0/+18
Pull drm updates from Dave Airlie: "Highlights: - dmemcg eviction support is good for low VRAM things like Steam Machine - AMD adds gfx6-8 modifier support for older GPUs that enables a bunch of wayland stuff - i915/xe has some new hw support but also a lot of display refactoring Everything: perf: - export perf_allow_ APIs for xe udmabuf: - remove default size limit of 64MB rust: - i/o rework (signed tag from driver-core tree) - add registration guard and registration data - fix unbounded lifetimes in ioctl handler args - fix a drm_dev_register race - gem_shmem: add DmaResvGuard helper - gpuvm: require send/sync for driver data - implement send/sync for GpuVaAlloc and GpuVmBo - add SmContext lifetime - rename dma_handle to dma_address - change pci_sriov_get_totalvfs return to unsigned int core: - create drm_of_get_panel_orientation - send per-connector hotplug events - add thunderbolt UBHR tunneling support connector: - add color format property dmem: - introduce a peak file - accept one region per limit - add dmemcg support for eviction gpusvm: - reorg code to give drivers more flexibility atomic: - add create_state callback and helper - add documentation on atomic commit lifetime buddy: - add per-order free - add used block scoreboard - fix UAF - test buffer clearance on resume - add phys_addr->block helper gem: - drop DRIVER_GEM_GPUVA flag ttm: - be more aggressive allocating below protection limit sched: - add test suite for concurrent job submissions hdmi: - hook the color format property in helpers mipi-dsi: - add MIPI_DSI_MODE_DSC_ALL_SLICES_IN_PKT bridge: - add atomic create callbacks - drop atomic reset - display-connector: don't autoenable HPD IRQ - trigger initial HPD for DP - ti-sn65dsi83: remove NO_HFP and NO_HBP mode flags - analogix_dp: switch to DP link training helpers dp: - add support for DSC max delta BPP edid: - parse panel type from DisplayID 2.x Display Parameters sysfb: - improve panel, stride, framebuffer size validation panel: - implement ref counting for struct drm_panel - himax-hx83121a: add backlight regulator support - novatek-nt36672a: Inline panel init sequences - visionox-vtdr6130: enable DSC - novatek-nt37801: Use mipi_dsi_*_multi() functions - samsung-s6d16d0: Fix prepare error handling - support Novatek NT36536 plus DT bindings - sofef00: fix backlight updates - osd101t2587: use mipi_dsi_*_multi interface - panel-edp: adjust timing for AUO displays - panel-lvds: support Opto Logic SCX1001511GGC49 - panel-simple: support Kyocera tcg070wvlq - panel-edp: quirks - AUO B116XAT04.3, CMN N116BCP-EA2, CSW MNB601LS1-8 - BOE NV116WH2-M30, BOE NT116WHM-N21, BOE NV116FH1-M31 - BOE NV116FH1-M30, NV140FHM-N5B, TM156VDXP25 - BOE NE160QDM-NY1, MB116AS01 - new: - Samsung ATNA40HQ08-0, Anbernic TD4310 - Chipone ICNA35XX, Ilitek ILI9488 - Ilitek ILI7807S, Renesas R63419 - MNE001BS6-2, MNF601BS4-1, Sharp LQ120P1JX51 virtio: - add support for save/restore virtio_gpu_objects - abort vq wait on device removal amdgpu: - add color format DRM property - initial compute pipe reset support - add GFX 6-8 modifier support - initial DCN 6.0.0 support - dmemcg eviction support - improved boundary checking for bios parsing - RAS updates and rework - VCN secure submission fixes - 8K panel fix - Display KUNIT tests - parse panel type from DisplayID - Align IP discovery to pci device lifetime - SOC15 register macro cleanups - UVD memory placement fixes - GFX9 mode2 reset fixes - drop unnecessary BUG/BUG_ON - GFX8 soft reset rework - enable soft reset on GFX8 - PSP/SMU 15.0.9 update - VI ASPM fix - userq fixes - amdgpu_vm_get_task_info_pasid lifetime fix - DC CACP support - change system_unbound_wq with system_dfl_wq - Loosen VFCT bios parsing to deal with pci=realloc - SI/SMU7 AC/DC switch fix - VM fence handling fix - GEM close optimisation - Apple Studio Display fixes - DC FRL fixes amdkfd: - initial compute pipe reset support - allow applications to opt out of sigbus on fatal errors - improve CRIU boundary checks - MQD handling rework - move TBA/TMA from system to device memory - avoid topology-lock in kfd_mmap - SVM eviction fixes radeon: - fix unset CONFIG_ACPI build i915: - Novalake (NVL display version 35) timing generator enabling - NVL DC3CO enabling - enable UBHR link rates on thunderbolt tunnels - Reduce Xe3+ PM demand peak bandwidth - enable pipe DMC error interrupts for display 30+ - add kunit tests for DP link config selection - refactor and document DP link recovery - i915/xe driver display probe/remove/suspend/resume/shutdown cleanup and unification - i915/xe display runtime PM unified - Break i915 and xe panic dependency on struct intel_framebuffer - Streamline Pre/Post-CSC LUT loops - drop TGL DC3DO support - CDCLK santization - fix HDMI scrambling enable - fix phys bo pread/pwrite with offset - add missing nospec on parallel submit slot - fix some NULL derefs xe: - drop force_execlist module param - gate observation streams with perf_allow_cpu - skip FORCE_WC and vm_bound check for external dma-bufs - dmemcg eviction support - remove unused NVL-S GuC - TLB invalidation improvements - NVL-S updated PCI-IDs and w/a - madvise: optimise invalidation path - fix infinite gt-reset loop in timeout recovery - update TTM device benefical_order - wait on external BO kernel fences in exec ioctl - add/use more KLV helpers - sriov: disable display in admin only PF mode - add RAS GPU health indicator - optimise TTM populate for DONTNEED BO - drop force_probe for NVL-s - add debugfs for pcode info amdxdna: - disable device buffer export nova: - build nova-core/nova-drm from drivers/gpu - export nova-core rust symbols (workaround) - GSP boot process consolidation - Boot GSP with vGPU enabled - TLV firmware image format support - Hopper/Blackwell fixes and cleanups - I/O projection adoption tyr: - firmware loading and MCU boot - add generic slot manager + MMU - GPU VM support ARM64 LPAE page tables - add kernel buffer object for internal allocations - add parser for Mali CSF - add MCU booting nouveau: - race fixes - check instmem iomapping at first use - add dmemcg support - expose NVDEC channels - add scanline position/head state support for GSP qxl: - convert simple encoder to regular ethosu: - add perf counter support etnaviv: - force flush on power register ops msm: - support DSC configuration with slice_per_pkt > 1 mxsfb: - fix disable sequence panthor: - support sparse mappings rockchip: - switch away from simple helpers - support YUV background color - fix layer config timeout - add edp support for rk3576 - add batch command submission function rocket: - error handling and NULL ptr deref fixes sun4i: - switch away from simple helpers imagination: - mark BXM-4-64 MC1 as support host1x: - support tegra264 tegra: - add DSI for tegra 20/30 v3d: - reduce PM runtime autosuspend delay - scheduler fixes and refactoring - deprecate v3d 3.3 and 4.1 - validate CPU job query boundaries hibmc: - improve plane format handling - switch to gem shmem mediatek: - cec: correct compat for mt7623-8167? exynos: - remove simple dependency - add error handling to encoder paths - take i2c adapter module reference" * tag 'drm-next-2026-08-20' of https://gitlab.freedesktop.org/drm/kernel: (2074 commits) drm/xe/mcr: Take vcs1/vecs1 into account for first media slice drm/xe: Fix a bug in pc_adjust_freq_bounds() drm/xe: Fix xe_device_probe() failure drm/xe/drm_ras: Move has_drm_ras check to drm_ras layer drm/xe/ras: Fix boot-time ras error processing drm/amd/display: make DC_RUN_WITH_PREEMPTION_ENABLED misuse a build error drm/amd/pm: silence uninitialized variable warnings drm/amdgpu: skip BOs being torn down during GTT recovery drm/amdgpu: Reject UVD message with invalid number of h265 refs drm/amdgpu: keep PRT mappings off the vm_bo state lists drm/amdgpu: fix nbif 6.3.1 l1 low power not functional drm/amd/display: fix BT.2020 YCbCr output CSC matrices for DCE drm/amd/display: fix BT.2020 YCbCr limited output CSC matrix drm/amdgpu: Implement insert_end for VCE 3 drm/amdgpu: Fix UVD min buffer sizes drm/amdgpu: Fix UVD decode image min size calculation drm/amdgpu: Fix UVD dpb min size calculation for H264 drm/amdgpu: Reject UVD message with dimensions above 4096 drm/amdgpu: check ASPM on the dGPU host link drm/radeon: fix autosuspend cleanup during teardown ...
2026-08-20Merge tag 'mm-stable-2026-08-18-18-39' of ↵Linus Torvalds2-14/+19
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