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9 daysMerge tag 'mm-stable-2026-10-19-21-33' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "selftests/mm: improve khugepaged coverage" (Kiryl Shutsemau): Give khugepaged a proper workout. Extend the tests to all supported mTHP orders, check exactly which windows collapsed, and make scan completion deterministic. Race collapse against faults, pinning, fork and remap; verify that the contents survive. Add coverage for whole-page-table zaps and memory pressure too. - "selftests/mm: separate GUP microbenchmarking from functional testing" (Sarthak Sharma): Untangle GUP benchmarking from correctness testing. Move the benchmark into tools/mm, add a standalone harness-based GUP selftest, and move shared helpers into tools/lib/mm. Give each tool one job instead of mixing timing measurements with correctness checks. Cover the mapping, pinning and batch-size combinations explicitly. - "mm: Switch device DAX to section-based vmemmap optimization" (Muchun Song): Apply section-based vmemmap optimization to device DAX. Rework the backing metadata layout to save memory while preserving the handling of device memory hotplug and its different alignment and lifetime requirements. - "mm: Introduce section-based vmemmap optimization for HugeTLB" (Muchun Song): Cut the memory consumed by HugeTLB's struct page array with section-based vmemmap optimization. Arrange the metadata so large huge pages need fewer backing pages, while keeping initialization, teardown and the various hugepage configurations straight. - "mm/huge_memory: clean up and decouple the anon and file split helpers" (Kairui Song): Separate anonymous and file-backed folio splitting, which have rather different locking and bookkeeping requirements. Move the work into separate helpers, drop dead checks and tidy swap-cache handling. Fix error paths, including one that could leave a folio frozen. Keep the swap cache cases separate from file-cache splitting. - "mm: Unconditional per-VMA locks and cleanups" (Dave Hansen): Make per-VMA locking unconditional and clean up the old conditional code around it. This removes configuration-dependent plumbing and lets callers depend on one locking model rather than carrying both cases along. - "memcg: remove the v1 soft limit" (Shakeel Butt): Remove the old cgroup v1 memory soft-limit machinery. This has long since been superseded by the newer memory-control interfaces; hauling around a separate reclaim scheme for it no longer buys us much. - "read proc/pid/smaps_rollup under per-vma lock" (Suren Baghdasaryan): Read /proc/PID/smaps_rollup using per-VMA locks where possible, rather than holding mmap_lock across the entire walk. Retain the contention fallback and add tearing tests. This considerably reduces latency when another thread is busy changing its mappings. - "mm/damon: introduce data access-as-a-data attribute" (SJ Park): Teach DAMON to expose memory access observations as data attributes, making them available to the probe and filtering machinery. Extend the interfaces, documentation and tests so the new information can be used rather than merely collected. - "Remove PG_private by using page/folio->private checks instead" (Zi Yan): Get rid of PG_private and use the folio's private pointer to say whether private data is attached. Convert the filesystem users, including erofs, f2fs and md, and clean up the old accessors and flags. There are a few special cases, notably swapcache and hugetlb, which need explicit care. - "mm: make userland page table freeing RCU-safe" (Lorenzo Stoakes): Make freeing userspace page tables safe against RCU readers. Sort out the page-table lifetime and locking rules so walkers cannot stumble over freed tables while mappings are being torn down. - "make unused huge shrinker memcg aware" (Qi Zheng): Make shmem's unused-huge-folio shrinker aware of memory cgroups, so reclaim can find those folios under the right memcg. Wire up the per-memcg tracking and its lifetime rules, and give the shrinklist its own lockdep class to avoid spurious dependency reports. - "mm: Drop pxd_ERROR()" (Anshuman Khandual): Remove the old pxd_ERROR() page-table checks and their architecture-specific baggage. Simplify the common page-table interfaces and callers now that these checks no longer serve a useful purpose. - "memcg: group struct fields by access pattern" (Shakeel Butt): Rearrange memcg's hot and cold fields according to how they're actually accessed. Keep frequently updated counters and their neighboring state from fighting over cachelines and reduce needless cacheline traffic. - "mm/damon/core: fix the size charged for a filter-trimmed region" (Donggeun Yoo): Fix DAMOS quota accounting when a filter trims a monitoring region. Charge only the part left after filtering, not the original region, and add KUnit coverage. Previously the excluded memory could eat into the quota and make schemes run more slowly than requested. - "mm/damon: add kunit and selftests for probes and probe weights" (SJ Park): Add more tests for DAMON probes and their weights, including validation and the results reported to userspace. This is mostly about catching regressions in the newer probe infrastructure before they become harder to diagnose. - "mm: memcontrol: constify the read side of the read side of the memcg API" (Tal Zussman): Mark the read-only parts of the memcg interface const, from folio and lruvec accessors to counters and swap helpers. Most of this is mechanical, but it makes the contracts clearer and lets the compiler catch accidental writes. - "mm/damon/vaddr: support {prep,apply}_probes" (SJ Park): Support the new prepare/apply probe operations in DAMON's virtual-address backend. This brings vaddr monitoring into line with the probe infrastructure and makes the added probe types useful there too. - "mm/mglru: clean up folio counters and flag usage" (Kairui Song): Simplify MGLRU's folio counters and flag handling. Remove redundant accounting paths and make the state transitions easier to follow without changing the intended reclaim policy. - "arch, mm/execmem: resolve confusion about set_direct_map_valid_noflush()" (Mike Rapoport (Microsoft)): Clarify and straighten out the set_direct_map_valid_noflush() interface across architectures and execmem. Make the requested mapping changes and the callers' expectations agree, rather than relying on subtly different architecture behavior. - "mm: zswap: free cold writeback folios promptly" (Alexandre Ghiti): Free zswap writeback folios as soon as their disk write completes. They are cold temporary buffers, so putting them on the LRU only makes reclaim rediscover them later. Extend swap-cache dropbehind and let zswap keep these folios off the LRU altogether. - "mm: gup: cleanup gup_fast call chain" (Aristeu Rozanski): Clean up the GUP-fast call chain and simplify how the fast-path helpers pass their arguments and results around. Keep the page-pin behavior the same while making the call sequence easier to maintain. - "mm: optimize zone-device memmap initialization" (Li Zhe): Speed up initialization of zone-device struct pages. Avoid redundant work when setting up large device-memory ranges, where touching every descriptor can get expensive. - "mm/zswap: shrink zswap_entry via a pool id" (Jianyue Wu): Reduce the size of zswap_entry by storing a compact pool identifier instead of a full pointer. Keep the pool lookup and lifetime handling correct while saving per-entry metadata. - "mm/damon: support access monitoring of hugetlb-backed memory" (Krishna Iyer): Let DAMON monitor hugetlb-backed memory too. Extend the relevant access checks and add coverage so those mappings no longer fall through a hole in the monitoring machinery. - "mm/execmem: fixes and cleanups for the ROX cache" (Mike Rapoport): Tidy execmem's read-only-executable cache and fix its handling of the awkward allocation and release cases. The aim is to make the cache's ownership and permission transitions more predictable. - "zsmallc: remove old object read API" (Sergey Senozhatsky): Drop zsmalloc's old object-read API and move its remaining users to the supported access mechanism. This removes a duplicate interface which we no longer need. - "mm/mempolicy: stop copying state in the interleave paths" (Gregory Price): Stop copying mempolicy state in the interleave paths when a reference to the existing policy will do. This avoids extra work and makes the ownership rules less obscure. - "mm/mglru: speed up inc_min_seq() and fix cold/hot inversions" (Barry Song): Make MGLRU's generation advancement cheaper and fix cases where cold and hot folios end up in the wrong order. Adjust the counter and list handling so reclaim doesn't keep passing over the better eviction candidates. - "mm: Fix MF_DELAYED handling on memory failure" (Lisa Wang): Treat MF_DELAYED as a partially completed memory-failure operation, not an outright failure. Propagate that result correctly through shmem and the generic handler, fix the extra-reference accounting, and add tests for the resulting SIGBUS behavior. - "tools/mm/page_owner_sort: fix --sort, add module filter, improve usage" (Ye Liu): Fix page_owner_sort's --sort handling, add module-based filtering and make the usage output more helpful. This makes the tool less frustrating when tracking down who is holding on to pages. - "mm/damon: move damos filter range arguments validation to core" (SJ Park): Move DAMOS filter range validation into the core, where all callers can share it. Also close the sysfs read-twice races which could pass inconsistent ranges, and add tests for invalid input. - "mm/damon: misc cleanups" (Zenghui Yu): Clean up a collection of small DAMON rough edges in the core, interfaces and tests. No large behavior change here, just simpler code and fewer opportunities for confusion. - "mm/damon: cleanup code, add test cases, and update guidances in docs" (SJ Park): Clean up DAMON's core and interfaces, add missing test cases and bring the documentation into line with the code. These changes should make the newer facilities easier to understand and maintain. - "mm/damon: introduce hugepage_size probe filter" (SJ Park): Add a DAMON probe filter for hugepage size. Let users select a range of folio sizes through sysfs, validate the range and document the new interface, so monitoring can concentrate on memory backed by the desired hugepage sizes. - "selftests/mm: pagemap_ioctl test fixes and cleanups" (Zenghui Yu): Fix some pagemap ioctl test assumptions and clean up their setup and reporting. Make failures point to the operation that went wrong rather than to test harness bookkeeping. - "mm: avoid large folio splits when swap is unavailable" (Johannes Weiner): Avoid splitting large folios merely to attempt swap when no swap space is available. There is little point paying for an expensive split when reclaim cannot actually swap the resulting pages out. - "mm: workingset: fix the shadow node budget under MGLRU" (Hui Zhu): Fix the workingset shadow-node budget with MGLRU enabled. Keep the shadow entries within the intended limits so refault tracking does not quietly consume more metadata than it should. - "selftests/mm: TAP output and global-state fixes" (Song Hu): Fix selftests which produce misleading TAP output or fail to restore global settings after a run. A test ought to leave the system as it found it, particularly when a whole suite follows behind. - "mm: remove page_swap_entry()" (Tal Zussman): Remove page_swap_entry() and convert its remaining users to the folio and swap-entry helpers. Lose an old page-level interface and make the swap paths a little more consistent. - "mm: refactor zonelist constructors and iterators" (Gregory Price): Refactor the zonelist construction and walk helpers to reduce duplicated logic. Keep the allocation ordering rules intact while making it clearer how zones are selected. - "mm: kmemleak: batch the struct page scan" (Breno Leitao): Scan adjacent struct pages in batches instead of taking kmemleak_lock once for every single page. This preserves scan coverage and the lock-hold bound, while cutting overhead substantially on debug kernels. - "mm/damon: misc improvements in tests and documents" (Zenghui Yu): Fix some DAMON selftests which leave kdamond running or fail under Python safe-path mode, and improve the KUnit coverage and documentation. Nothing especially glamorous, but these are worth doing. - "mm/damon: introduce probe_hits_wsum DAMOS core filter" (SJ Park): Add a DAMOS core filter using weighted probe-hit counts. This gives schemes another way to select regions based on what the monitoring probes observed. - "mm/mglru: fix ineffective memory protection for non-kswapd reclaim" (Ridong Chen): Fix MGLRU's memory protection handling for reclaim outside kswapd. The protection settings weren't having the intended effect in these paths, leaving protected memory more exposed than requested. - "mm/damon: improve readability, clarity and test coverage" (SJ Park): Simplify a handful of DAMON core helpers, clarify their behavior and expand test coverage. There are no intended userspace-visible changes in this batch. - "mm: replace PF_KCOMPACTD/PF_KSWAPD with kthread_func()" (Kefeng Wang): Stop identifying reclaim and compaction workers through the PF_KSWAPD and PF_KCOMPACTD task flags. Use their kthread functions instead and remove the redundant flag plumbing. - "mm/hugetlb: fix surplus accounting and availability checks during demotion" (Longlong Xia): Fix HugeTLB surplus accounting and availability checks when demoting huge pages. Keep the counters and reservation decisions consistent as one huge page turns into several smaller ones. - "mm/damon: add kunit tests for probe_hits handling and probe params validation" (Jason Angelov): Add KUnit tests for DAMON probe-hit handling and invalid probe parameters. These cover edge cases that were too easy to miss in ordinary monitoring tests. - "mm/damon: fix misc bugs in kunit, quota goals and sysfs refresh_ms" (SJ Park): Fix a few DAMON bugs in KUnit tests, quota-goal handling and the sysfs refresh interval. Small fixes, but the incorrect results and control behavior were real. - "mm: zswap: optimize zswap invalidate and store" (Kefeng Wang): Simplify zswap's invalidate and store paths to avoid avoidable lookups and work. Keep the entry lifetime rules intact while making those frequent operations cheaper. - "mm: replace custom ratelimiting logic" (Pedro Falcato): Replace hand-rolled MM rate limiting with the common kernel helpers. There is no need to maintain another local version of the same mechanism. - "mm/vmalloc: minor cleanups" (Ye Liu): Tidy some vmalloc initialization and reporting code, and pull duplicated vmap-area insertion work into a helper. No functional changes are intended. - "mm/mglru: clean up isolate_folios for readability and clarity" (Ridong Chen): Clean up MGLRU's isolate_folios() so the decisions are easier to read and verify. Keep reclaim behavior unchanged while removing unnecessary twists in the control flow. - "Catch automatic storage in IDA and Maple Tree definitions" (Yury Norov): Catch IDA and maple-tree definitions placed in automatic storage where the lifetime rules are wrong or easy to get wrong. Add checks so such mistakes are harder to slip through unnoticed. - "mm, swap: some random fixes and cleanups" (Kemeng Shi): Fix and simplify a few unrelated swap paths, removing redundant work and tidying up error handling. A small collection of things which were better fixed than left lying around. - "mm/page_io: folio conversion cleanups" (Tal Zussman): Finish some page-to-folio conversions in swap I/O, removing obsolete wrappers and using folio operations consistently. The I/O behavior is intended to remain the same. - "mm/swap: skip empty clusters in the swapoff scan" (Youngjun Park): Skip empty swap clusters during swapoff instead of walking slots which have nothing to release. This avoids pointless work on sparsely used swap devices. - "mm: trace: decode architecture-specific VMA flags" (Meijing Zhao): Teach the VMA trace output to decode architecture-specific flags, rather than leaving them as unexplained bits. That should make tracing a good deal more useful when debugging unusual mappings. - "mm, swap: don't spin on a bad swap entry" (Breno Leitao): Stop repeatedly retrying a swap entry which is already known to be bad. Make the error path terminate cleanly instead of wasting CPU chasing an entry that cannot be used. - "mm/page_isolation: fix UBSAN shift-out-of-bounds in isolate_single_pageblock" (Qi Xi): Fix an out-of-range shift in isolate_single_pageblock() and tighten its associated boundary handling. UBSAN found the issue; the result should be more robust pageblock isolation. - "mm: khugepaged: fix tracepoint UAF" (Vernon Yang): Fix a use-after-free in khugepaged tracepoint handling. Make sure the information recorded by tracing stays valid for as long as the trace event needs it. - "mm/damon: fix DAMOS bugs in core, paddr and vaddr" (SJ Park): Fix several DAMOS problems across the core and physical- and virtual-address backends. The changes close error cases and bring the implementations back into agreement. - "mm/hugetlb_cgroup: move the per-node usage along with the folio" (Hongfu Li): Move HugeTLB per-node usage accounting when folios migrate between nodes or are reparented to another cgroup. Otherwise numa_stat can retain stale charges and even underflow when the folio is freed. - "docs/core-api: memory-allocation: add k[mz]alloc_obj() and clarify kmalloc" (Mike Rapoport): Document the typed k[mz]alloc_obj() allocation helpers and clear up some kmalloc guidance. Make it easier for callers to choose the right interface. - "selftests/mm: Validate selections and scope memfd_secret setup" (Tianyi Chen): Check selftest selections before running and confine memfd_secret setup to the cases that actually need it. Avoid confusing failures caused by the test harness itself. - "mm/damon: move zero damos quota target_value handling to the core layer" (SJ Park): Handle a zero DAMOS quota goal target in the core rather than making each user of the interface invent its own rule. Keep quota decisions consistent across callers. - "mm/damon: Introduce a huge page collapsing mechanism using auto tuning" (Asier Gutierrez): Add an auto-tuned DAMON mechanism for collapsing huge pages. Use monitoring feedback to decide when collapse is worthwhile rather than forcing one fixed policy onto every workload. - "kmemleak: fix stale documentation and raise the verbose default" (Breno Leitao): Bring the kmemleak documentation up to date and require a third confirming scan before verbose kernels print a suspected leak. The extra scan helps suppress transient false positives in noisy debug builds. - "mm/memory: improve insert_pages() error handling" (Avi Weiss): Tighten insert_pages() error handling so partial failures are reported and cleaned up consistently. The caller should not have to guess how far the operation got. - "mm/damon: allow NULL or unstarted damon_ctx parameter for damon_call()" (SJ Park): Make damon_call() handle NULL and not-yet-started contexts safely. Simplify the rules for callers and avoid an indefinite wait on an invalid state. - "mm/damon: introduce pgidle_set probe filter type" (SJ Park): Add a pgidle_set DAMON probe filter, giving monitoring users another way to select pages by their idle-tracking state. Wire it through the filter interfaces and tests. - "mm/damon/core: remove unused helper functions" (Cheng-Han Wu): Remove DAMON core helpers which no longer have callers. Keep the API surface smaller rather than retaining dead code just in case. - "mm: stop calling pmd_folio() on special PMDs" (Gregory Price): Avoid calling pmd_folio() on special PMD mappings that have no struct page. The old assumption could fault in procfs walkers; use the normal-folio checks and handle those mappings properly. - "mm: remove three unused helpers from mm.h" (Tal Zussman): Remove three unused helpers from mm.h. Fewer obsolete interfaces for the next person to stumble over. - "mm/damon: improvements in efficiency, error handling, documents" (Liew Rui Yan): Skip needless DAMOS quota work once the quota is full, propagate a missing sysfs error and tidy a couple of comments. The ignored error could make a monitoring-start request appear successful when it wasn't. - "docs/mm/damon/design: add explanation of nr_snapshots" (Liew Rui Yan): Explain DAMON's nr_snapshots accounting in the design documentation and straighten out the associated terminology. Make it clearer what users should expect from that counter. - "selftests/cgroup: fixes for test_zswap on single core VM" (Wilson Felipe Pereira): Fix two test_zswap failures on single-CPU VMs. Wait for the exiting child's cgroup to become unpopulated before reconfiguring it, and avoid another test assumption which breaks under constrained scheduling. - "docs/ksm: fix advisor documentation and comment" (Jinjiang Tu): Correct the KSM advisor documentation and a misleading code comment. Keep the description aligned with how the advisor actually works. - "Fix bugs in HugeTLB allocation when mem_cgroup_charge_hugetlb() fails" (Ackerley Tng): Fix HugeTLB allocation cleanup when the memcg charge fails. Make sure failure exits undo what was allocated rather than leaving stale accounting or resources behind. - "mm, memcg: fix memory.peak reset clobbering other fds' watermark" (Ridong Chen): Fix memory.peak reset handling so resetting one file descriptor doesn't overwrite the watermark kept for another. Keep those per-open measurements independent as intended. - "mm: reject zone device folios in more folio walkers" (Gregory Price): Reject zone-device folios in page walkers that cannot safely handle them. Extend the existing checks rather than assuming every folio has ordinary system-memory backing. - "percpu: remove code with no effect" (Sang-Heon Jeon): Remove a few pieces of percpu code which no longer do anything. There is no reason to keep maintaining dead paths. * tag 'mm-stable-2026-10-19-21-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (539 commits) mm: shmem: assign a lock class to the unused huge shrinklist mm: vmscan: put rotation-missed folios at the LRU tail mm: kmemleak: scan the struct page array in MAX_SCAN_SIZE batches mm: kmemleak: move the struct page scan into a helper mm/damon: document that a zero sample_interval is accepted mm/damon: fix typos in comments mm/damon/sysfs: propagate damon_call() error in turn_damon_on mm/damon/core: skip quota score setup when the quota is full mm/damon/tests/core-kunit: test the size charged for a filter-trimmed region mm/damon/core: charge only the part of a region the filter left mm: disallow raw PFN mappings of huge/shared zeropage selftests/mm: zap whole PTE tables in the khugepaged race harness selftests/mm: add memory-pressure threads to the khugepaged race harness selftests/mm: race the collapse of windows with holes selftests/mm: add khugepaged race harness selftests/mm: check that one khugepaged pass collapses one window selftests/mm: run every supported collapse order by default selftests/mm: cover a shared-source collapse write race selftests/mm: parameterize the mixed-source collapse case by source order selftests/mm: add order-parameterized khugepaged collapse cases ...
11 daysMerge tag 'kbuild-7.4-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux Pull Kbuild / Kconfig updates from Nathan Chancellor: "Kbuild: - Suppress compiler flags in debug info for external module builds - Use '-fmacro-prefix-map' in more places in the build - Merge initial set of changes from Lorenzo's speed up series, along with some fixes found through testing: - Avoid allocating .modinfo in vmlinux - Speed up kallsyms by indexing symbols by token and outputting binary data to disk directly then including in assembly via .incbin - Don't sort $(NM) output when unnecessary - Only emit relocations on the final vmlinx link - Reimplement mksysmap in C - Move many cc-option and ld-option calls into the Kconfig stage to cache their results - Use pigz for gzip compression when available - Move gen_init_cpio and gen_initramfs.sh from usr/ to scripts/ - Add a TOML configuration to scripts/container and update documentation accordingly - Add a generic, opt-in mechanism for checking that headers can compile standalone - Update machine function splitting argument for LLVM 24 rename in AutoFDO build - Miscellaneous minor clean ups, fixes, and hardening, mostly found/fixed via LLMs Kconfig: - Turn recursive ranges into an error - Fix savedefconfig for defaults that were adjusted for being out of range and revert a previously applied workaround - Improvements and hardening around integer and hexadecimal values - Emit a warning when selecting or implying a choice symbol, which has no effect - Emit a warning when KCONFIG_PROBABILITY is malformed - Introduce def_string / def_int / def_hex to mirror the existing def_bool / def_tristate to succinctly set a value and type at the same time. - Add cc-option-str and ld-option-str macros to act like Kbuild's cc-option and ld-option, returning the string when the option is supported, allowing many checks to be moved into Kconfig - Minor usability improvements to Kconfig tests" * tag 'kbuild-7.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (59 commits) kbuild: AutoFDO: Update split machine function argument for upstream rename kbuild: Mark the initcall ordering recipe as recursive kbuild: Mark the gzip recipes as recursive localmodconfig: Explicitly report boolean configs during integrity check scripts/make_fit: Ignore schema checks when decomposing DTBs clang-tools: Import os for broken pipe handling kconfig: use the value argument in sym_get_near_range_bound() kconfig: fix infinite loop in conf_choice() when no choice value is visible kconfig: cleanup stale comment about 'keys' array kconfig: Improve ergonomics around disabling warnings with cc-option scripts/Kconfig.toolchain: Drop compiler symbols from dependencies checkkconfigsymbols.py: Parse Git status output line by line gen_init_cpio: stop parsing on lines with a missing argument list .gitignore: drop Module.markers .gitignore: ignore pacman package signatures kbuild: add header check facility as a manually run static analyzer Documentation: dev-tools: refer to user ID rather than id Documentation: dev-tools: update container.rst with config file scripts: add TOML config to container tool kconfig: tests: {old,save}defconfig: Forward dynamic keyword arguments ...
11 daysMerge __{get,put}_user() removal branchLinus Torvalds
This is long over-due: the __get_user() and __put_user() functions are entirely historical, and are never the rigth thing to use any more. And when mis-used (read: every case) they are not only slower than the right thing, but also insecure because they don't check the user address range. Most of the usage sites have been converted long ago, but various left-overs remained. So this started out as a single patch that I wrote as a "show people how to convert __{get,put}_user() to modern code". In particular, Thomas last year implemented the very nice new scoped user access region helpers (see commit e497310b4ffb: "uaccess: Provide scoped user access regions") that makes the modern interfaces particularly easy to use and really removes any excuse for the old horrors. That small example patch then grew to this, partly using Claude as a glorified coccinelle script to apply the pattern to other places. There were a few different reasons for using __put_user() and __get_user() rather than the alternatives, but the original historical one was performance: when doing multiple accesses off the same base pointer, doing a single range check followed by multiple non-checked accesses used to create smaller and faster code. The keyword here is "used to". It hasn't been true for years, because the range check isn't actually the real cost these days. The real cost of user accesses on modern hardware is turning the user accesses on and off in the first place (on x86, using the STAC/CLAC instructions). Those sequences get turned into 'scoped_user_read_access() { }' blocks, see for example that first patch in the series: "signal: use scoped user access for old-style sigaction". Another, historical reason for using __get_user() and friends is that you actually want to do a kernel pointer access, but the pointer might not be entirely reliable (typically during fault handling), so you want to have exception handling for the kernel access. The modern way to do that kind of non-faulting kernel access is using "get_kernel_nofault()", but some code predates that helper existing at all, and used __get_user() as a way to just get a memory access with exception handling. For that pattern, see for example "alpha: use get_kernel_nofault() in dik_show_code()" A third bad reason for using __get_user() and friends was that the proper get_user() had a "might_fault()" in it, and code that ran in atomic regions but hadn't disabled page faults would result in a warning. That kind of code needs to explicitly disable page faults, because "atomic region" is not well defined at run-time and can be invisible (eg a preempt-off region in a non-preemptible kernel). See "vdpa_sim: disable page faults around vringh_need_notify_iotlb()" for an example of that pattern, where the local_bh_disable() now also grows a pagefault_disable(), which makes the normal get_user() no longer warn about the user access in non-process context, because it can see that the potential page fault will not cause problems. And finally, the really nasty reason to use __get_user() and friends: pointers that can be either kernel pointers or user pointers. We've gotten rid of almost all such cases, but a couple remained. See for example "x86/sev: Use explicit user-or-kernel accessors for #VC memory operands". NOTE! This series removes all __get/put_user() calls from generic code but only does the final removal of the whole interface on x86. Other architectures have not been entirely converted, for a variety of reasons: - arm64 makes __{get,put}_user() be exactly the same as {get,put}_user() so it's harmless and didn't have the dangers of the legacy use cases. - any architecture that uses <asm-generic/uaccess.h> will still use __{get,put}_user as the underlying helper function name - several architectures had some legacy uses that weren't entirely trivial and I didn't want to extend this patch series to things that I don't know and that don't really matter. but I did do a couple of the obvious "follows the exact same pattern" just because it could be done mindlessly and automatically. Let's see if I broke anything, but we should have done this years ago. * uaccess-cleanups: (48 commits) drm/i915/gem: ignore errors on presumed_offset write-back powerpc/align: use get_user_instr() for a user-mode instruction powerpc/signal64: use scoped user access in setup_trampoline() powerpc/signal64: use get_user() for the single context reads powerpc/signal32: use get_user() for the single context reads KVM: PPC: Book3S HV: use get_user()/put_user() for the HPT fd powerpc/powernv: use get_user()/put_user() in the LPC debugfs files s390: use get_user()/put_user() instead of the unchecked variants ARM: OABI: use scoped user access in epoll_put_uevent() ARM: signal: stop using __put_user() for the signal frame ARM: signal: check the FDPIC function descriptor address alpha: split the prefetch check in do_page_fault() by mode openrisc: use get_kernel_nofault() in show_registers() alpha: use get_kernel_nofault() in dik_show_code() nios2: use scoped user access for the signal frame nios2: check the signal frame address before writing to it hexagon: use scoped user access for the signal frame alpha: use scoped user access when setting up signal frames alpha: use scoped user access in the sigreturn path alpha: use scoped user access in osf_sigaction() ...
12 daysnios2: use scoped user access for the signal frameLinus Torvalds
rt_setup_ucontext() and rt_restore_ucontext() move the saved registers with __put_user() and __get_user(), OR-ing the errors together, relying on the access_ok() done on the whole frame by setup_rt_frame() and do_rt_sigreturn(). setup_rt_frame() writes the ucontext flags and link the same way. Do those accesses inside scoped_user_{write,read}_access() instead, with unsafe_{put,get}_user(). The gregs pointer is now derived inside each scope, from the pointer the scope checked. restore_altstack() is called after the scope. The access_ok() calls stay: do_rt_sigreturn() still needs its own for the __copy_from_user() of the signal mask. A fault part way through now stops at the first failing access instead of carrying on. Either way the task gets SIGSEGV. nios2 has no user_access_begin(), so the accesses themselves are the same as before. This is part of getting rid of __get_user() and __put_user() entirely. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 daysnios2: check the signal frame address before writing to itLinus Torvalds
setup_rt_frame() never checks that the signal frame it builds is in user space. The frame address comes from the user stack pointer (or the alternate signal stack), and nios2's __put_user() is a plain store with no address check. The kernel runs in supervisor mode above TASK_SIZE, so those stores succeed. The errors are OR-ed together and the frame setup carries on, so even though copy_siginfo_to_user() fails its own check, the ucontext header and every saved register are still written. A task that points its stack pointer at kernel memory and takes a signal gets its own register values written there. Check the whole frame with access_ok() before writing any of it, as the sigreturn side already does. This goes back to the original nios2 signal code in commit b53e906d255d ("nios2: Signal handling support"). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 daysnios2: ksyms: Declare __mulsi3 exportThomas Weißschuh
GCC may emit libcalls to __mulsi3(). As modpost is not aware that this function is provided through the linked in libgcc, it fails: ERROR: modpost: kernel/locking/test-ww_mutex.ko: symbol '__mulsi3' undefined! ERROR: modpost: kernel/time/test_udelay.ko: symbol '__mulsi3' undefined! ERROR: modpost: kernel/resource_kunit.ko: symbol '__mulsi3' undefined! ERROR: modpost: fs/fuse/virtiofs.ko: symbol '__mulsi3' undefined! etc. Make sure modpost can see the symbol from libgcc. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202610171933.J4bFOfL8-lkp@intel.com/ Fixes: 2fc8483fdcde ("nios2: Build infrastructure") Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
2026-10-13nios2: fix __wsum type degradation in csum_fold()Keith Busch
csum_fold() shifts a bitwise __wsum type, which sparse reports as "restricted __wsum degrades to integer". Sparse only checks the body of a static inline once something instantiates it, so this went unnoticed until a recent block layer change added the first csum_fold() caller to a file built on this architecture. Force cast to a __u32 for the shift, as the other architectures do. Fixes: eea9507a69d6 ("nios2: Library functions") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202609222053.5gjiJjtb-lkp@intel.com/ Signed-off-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
2026-10-11kbuild: Mark the gzip recipes as recursiveKees Cook
Since commit 48ebe1cbbeb51 ("kbuild: compress the kernel with pigz if available"), cmd_gzip runs pigz through scripts/jobserver-exec, which takes the job slots make has free. GNU Make passes the jobserver pipe only to recipes it treats as recursive, but leaves --jobserver-auth in MAKEFLAGS for all of them. The make 4.3 in CentOS Stream 9 also hides the pipe in sub-makes (a backport of the fix for GNU Make bug 58232), so jobserver-exec cannot open it, runs pigz on one thread, and prints: WARNING: Unable to reopen jobserver read-side pipe: FileNotFoundError(2, 'No such file or directory') Mark every recipe that can run cmd_gzip as recursive with "+", as commit ecab4115c44cc ("kbuild: mark `rustc` (and others) invocations as recursive") did for rustc. Besides the $(call if_changed,gzip) rules, this covers those that choose gzip through a variable: the built-in initramfs in usr/Makefile (which rcutorture's kvm.sh builds), the EFI zboot image, and the arm, csky, and mips compressed images. As with rustc, "make -n" now runs these recipes, including those that choose through a variable when they select another compressor. Also update the gzip entry in Documentation/kbuild/makefiles.rst, as suggested in review. Tested with GNU Make 4.3 plus CentOS Stream 9's make-4.3-cloexec.patch, GCC 16.2.0, and -j64, on ARCH=x86_64, arm64, and arm defconfig, and ARCH=x86_64 defconfig with a built-in initramfs: none of them prints the warning, and pigz gets the free job slots (-p 54, 64, and 50 for the kernel image). Without this change, the x86_64 builds print it for the kernel image and for the initramfs. Reported-by: Paul E. McKenney <paulmck@kernel.org> Closes: https://lore.kernel.org/all/0ddb5e5e-f801-444c-aa98-0cfe814a3026@paulmck-laptop/ Fixes: 48ebe1cbbeb51 ("kbuild: compress the kernel with pigz if available") Assisted-by: LLM Reviewed-by: Nicolas Schier <n.schier@fritz.com> Acked-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Signed-off-by: Kees Cook <kees@kernel.org> Tested-by: Paul E. McKenney <paulmck@kernel.org> Link: https://patch.msgid.link/20261010081914.540611-1-kees@kernel.org Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2026-10-08mm: userland pgtable freeing is RCU-safe now, remove leftover bitsLorenzo Stoakes (ARM)
Now every architecture has been converted to support CONFIG_MMU_GATHER_RCU_TABLE_FREE, this configuration option no longer makes any sense to keep around. Therefore remove it, and remove all the dead code that existed for !CONFIG_MMU_GATHER_RCU_TABLE_FREE architectures previously. Additionally, CONFIG_MMU_GATHER_TABLE_FREE is no longer necessary, as all architectures instead use CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE when a custom __tlb_remove_table() is required, so remove this too. A number of architectures only enabled CONFIG_MMU_GATHER_RCU_TABLE_FREE if CONFIG_MMU was set, however the mmu_gather logic only actually does something meaningful if CONFIG_MMU is set (mmu_gather.c is only compiled in this case, for instance). As a result, there's no need to gate any of this logic on CONFIG_MMU explicitly. CONFIG_PT_RECLAIM however does have a strict dependency on CONFIG_MMU, so make this dependency explicit. Additionally, correct comments to remove references to non-RCU page table gathering and make it clear that this is not 'semi-RCU', nor has it been since commit 1fb3d8c20bfa ("mm/mmu_gather: replace IPI with synchronize_rcu() when batch allocation fails"). With this change in place the kernel policy is now that userspace page tables are freed after an RCU grace period, and thus it is now safe to unconditionally perform page table walks under RCU, safe in the knowledge that page tables will not be freed underneath the walker. This is all that is guaranteed, however, so naturally it is still incumbent upon page table walkers to ensure that the page table entries are as expected. Link: https://lore.kernel.org/20260925-rcu-pagetable-freeing-v5-11-31e91065fea4@kernel.org Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Kiryl Shutsemau (Meta) <kas@kernel.org> Reviewed-by: Lance Yang <lance.yang@linux.dev> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Liam R. Howlett <liam@infradead.org> 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: Usama Arif <usama.arif@linux.dev> Cc: Guo Ren <guoren@kernel.org> Cc: Brian Cain <bcain@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Simon Schuster <schuster.simon@siemens-energy.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Stafford Horne <shorne@gmail.com> Cc: Rich Felker <dalias@libc.org> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Paul Walmsley <pjw@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Michal Simek <monstr@monstr.eu> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Richard Henderson <richard.henderson@linaro.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: James Bottomley <james.bottomley@hansenpartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Christophe Leroy <chleroy@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Johannes Berg <johannes@sipsolutions.net> 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: H. Peter Anvin <hpa@zytor.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Peter Xu <peterx@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Hugh Dickins <hughd@google.com> Cc: Qi Zheng <qi.zheng@linux.dev>
2026-10-08mm: enable MMU_GATHER_RCU_TABLE_FREE for most 2-level architecturesLorenzo Stoakes (ARM)
Commit e3ecf7c7d082 ("mm: pgtable: convert some architectures to use tlb_remove_ptdesc()") updated a number of architectures from using pagetable_dtor() + tlb_remove_page_ptdesc() to using tlb_remove_ptdesc() in __pte_free_tlb(). This is meaningful as tlb_remove_ptdesc() allows for RCU page table freeing if CONFIG_MMU_GATHER_RCU_TABLE_FREE is specified. The csky, hexagon, nios2, openrisc, sh (except X2) and m68k-sun3 architectures all have 2 levels of page tables, so the only page tables ever freed by mmu_gather are PTEs, so this update suffices to ensure that every page table freed by the mmu_gather mechanism is freed under RCU. Therefore, update all of these architectures to select CONFIG_MMU_GATHER_RCU_TABLE_FREE. This forms part of an overall effort to switch every architecture to this mode. Link: https://lore.kernel.org/20260925-rcu-pagetable-freeing-v5-2-31e91065fea4@kernel.org Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Kiryl Shutsemau (Meta) <kas@kernel.org> Reviewed-by: Lance Yang <lance.yang@linux.dev> Cc: David Hildenbrand <david@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Liam R. Howlett <liam@infradead.org> 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: Usama Arif <usama.arif@linux.dev> Cc: Guo Ren <guoren@kernel.org> Cc: Brian Cain <bcain@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Simon Schuster <schuster.simon@siemens-energy.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Stafford Horne <shorne@gmail.com> Cc: Rich Felker <dalias@libc.org> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Paul Walmsley <pjw@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Michal Simek <monstr@monstr.eu> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Richard Henderson <richard.henderson@linaro.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: James Bottomley <james.bottomley@hansenpartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Christophe Leroy <chleroy@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Johannes Berg <johannes@sipsolutions.net> 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: H. Peter Anvin <hpa@zytor.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Peter Xu <peterx@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Hugh Dickins <hughd@google.com> Cc: Qi Zheng <qi.zheng@linux.dev>
2026-10-06mm: drop pxd_ERROR()Anshuman Khandual
There are no more users left for any pxd_ERROR() either in generic MM or in the platform MM. Hence all these platform macros along with their generic fallback could be dropped across the tree. Link: https://lore.kernel.org/20260831054331.625505-9-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k Acked-by: David Hildenbrand (Arm) <david@kernel.org> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Helge Deller <deller@gmx.de> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: James Bottomley <james.bottomley@HansenPartnership.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Rich Felker <dalias@libc.org> Cc: Samuel Holland <samuel.holland@sifive.com> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
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/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>
2026-07-12ptrace, treewide: Rename ptrace_report_syscall_entry() to ↵Thomas Gleixner
ptrace_report_syscall_permit_entry() The return value of that function is boolean and tells the caller whether to permit the syscall processing or not. Rename the function so the purpose is clear and make the return type bool. Signed-off-by: Thomas Gleixner <tglx@kernel.org> Tested-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com> Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com> Reviewed-by: Radu Rendec <radu@rendec.net> Reviewed-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Magnus Lindholm <linmag7@gmail.com> Link: https://patch.msgid.link/20260707190254.280015701@kernel.org
2026-05-28uaccess: unify inline vs outline copy_{from,to}_user() selectionYury Norov
The kernel allows arches to select between inline and outline implementations of the copy_{from,to}_user() by defining individual INLINE_COPY_FROM_USER and INLINE_COPY_TO_USER, correspondingly. However, all arches enable or disable them always together. Without the real use-case for one helper being inlined while the other outlined, having independent controls is excessive and error prone. Switch the codebase to the single unified INLINE_COPY_USER control. Link: https://lore.kernel.org/20260425020857.356850-3-ynorov@nvidia.com Signed-off-by: Yury Norov <ynorov@nvidia.com> Tested-by: Alice Ryhl <aliceryhl@google.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christophe Leroy (CS GROUP) <chleroy@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-23Merge tag 'nios2_updates_for_v7.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux Pull nios2 fixes from Dinh Nguyen: - Implement _THIS_IP_ for inline asm - Add Simon Schuster as a maintainer and mark the NIOS2 as Supported * tag 'nios2_updates_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux: nios2: Implement _THIS_IP_ using inline asm MAINTAINERS: arch/nios2: Add Simon Schuster as co-maintainer
2026-05-21nios2: Implement _THIS_IP_ using inline asmMarco Elver
Both GCC [1] and Clang [2] consider the generic version of _THIS_IP_ to be broken: #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) In particular, the address of a label is only expected to be used with a computed goto. While the generic version more or less works today, it is known to be brittle and may break with current and future optimizations. For example, Clang -O2 always returns 1 when this function is inlined: static inline unsigned long get_ip(void) { return ({ __label__ __here; __here: (unsigned long)&&__here; }); } Fix it by overriding _THIS_IP_ in <asm/linkage.h> (which is included by <linux/instruction_pointer.h>) using an architecture-specific inline asm version. Additionally, avoiding taking the address of a label prevents compilers from emitting spurious indirect branch targets (e.g. ENDBR or BTI) under control-flow integrity schemes. Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120071 [1] Link: https://github.com/llvm/llvm-project/issues/138272 [2] Signed-off-by: Marco Elver <elver@google.com> Reviewed-by: David Laight <david.laight.linux@gmail.com> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
2026-05-21ring-buffer: Flush and stop persistent ring buffer on panicMasami Hiramatsu (Google)
On real hardware, panic and machine reboot may not flush hardware cache to memory. This means the persistent ring buffer, which relies on a coherent state of memory, may not have its events written to the buffer and they may be lost. Moreover, there may be inconsistency with the counters which are used for validation of the integrity of the persistent ring buffer which may cause all data to be discarded. To avoid this issue, stop recording of the ring buffer on panic and flush the cache of the ring buffer's memory. Fixes: e645535a954a ("tracing: Add option to use memmapped memory for trace boot instance") Cc: stable@vger.kernel.org Cc: Will Deacon <will@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Ian Rogers <irogers@google.com> Link: https://patch.msgid.link/177751969602.2136606.12031934362587643488.stgit@mhiramat.tok.corp.google.com Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-04-05mm: convert do_brk_flags() to use vma_flags_tLorenzo Stoakes (Oracle)
In order to be able to do this, we need to change VM_DATA_DEFAULT_FLAGS and friends and update the architecture-specific definitions also. We then have to update some KSM logic to handle VMA flags, and introduce VMA_STACK_FLAGS to define the vma_flags_t equivalent of VM_STACK_FLAGS. We also introduce two helper functions for use during the time we are converting legacy flags to vma_flags_t values - vma_flags_to_legacy() and legacy_to_vma_flags(). This enables us to iteratively make changes to break these changes up into separate parts. We use these explicitly here to keep VM_STACK_FLAGS around for certain users which need to maintain the legacy vm_flags_t values for the time being. We are no longer able to rely on the simple VM_xxx being set to zero if the feature is not enabled, so in the case of VM_DROPPABLE we introduce VMA_DROPPABLE as the vma_flags_t equivalent, which is set to EMPTY_VMA_FLAGS if the droppable flag is not available. While we're here, we make the description of do_brk_flags() into a kdoc comment, as it almost was already. We use vma_flags_to_legacy() to not need to update the vm_get_page_prot() logic as this time. Note that in create_init_stack_vma() we have to replace the BUILD_BUG_ON() with a VM_WARN_ON_ONCE() as the tested values are no longer build time available. We also update mprotect_fixup() to use VMA flags where possible, though we have to live with a little duplication between vm_flags_t and vma_flags_t values for the time being until further conversions are made. While we're here, update VM_SPECIAL to be defined in terms of VMA_SPECIAL_FLAGS now we have vma_flags_to_legacy(). Finally, we update the VMA tests to reflect these changes. Link: https://lkml.kernel.org/r/d02e3e45d9a33d7904b149f5604904089fd640ae.1774034900.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Acked-by: Paul Moore <paul@paul-moore.com> [SELinux] Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: "Borislav Petkov (AMD)" <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kees Cook <kees@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Ondrej Mosnacek <omosnace@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <linux@armlinux.org.uk> Cc: Stephen Smalley <stephen.smalley.work@gmail.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Will Deacon <will@kernel.org> Cc: xu xin <xu.xin16@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05arch, mm: consolidate empty_zero_pageMike Rapoport (Microsoft)
Reduce 22 declarations of empty_zero_page to 3 and 23 declarations of ZERO_PAGE() to 4. Every architecture defines empty_zero_page that way or another, but for the most of them it is always a page aligned page in BSS and most definitions of ZERO_PAGE do virt_to_page(empty_zero_page). Move Linus vetted x86 definition of empty_zero_page and ZERO_PAGE() to the core MM and drop these definitions in architectures that do not implement colored zero page (MIPS and s390). ZERO_PAGE() remains a macro because turning it to a wrapper for a static inline causes severe pain in header dependencies. For the most part the change is mechanical, with these being noteworthy: * alpha: aliased empty_zero_page with ZERO_PGE that was also used for boot parameters. Switching to a generic empty_zero_page removes the aliasing and keeps ZERO_PGE for boot parameters only * arm64: uses __pa_symbol() in ZERO_PAGE() so that definition of ZERO_PAGE() is kept intact. * m68k/parisc/um: allocated empty_zero_page from memblock, although they do not support zero page coloring and having it in BSS will work fine. * sparc64 can have empty_zero_page in BSS rather allocate it, but it can't use virt_to_page() for BSS. Keep it's definition of ZERO_PAGE() but instead of allocating it, make mem_map_zero point to empty_zero_page. * sh: used empty_zero_page for boot parameters at the very early boot. Rename the parameters page to boot_params_page and let sh use the generic empty_zero_page. * hexagon: had an amusing comment about empty_zero_page /* A handy thing to have if one has the RAM. Declared in head.S */ that unfortunately had to go :) Link: https://lkml.kernel.org/r/20260211103141.3215197-4-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Helge Deller <deller@gmx.de> [parisc] Tested-by: Helge Deller <deller@gmx.de> [parisc] Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Magnus Lindholm <linmag7@gmail.com> [alpha] Acked-by: Dinh Nguyen <dinguyen@kernel.org> [nios2] Acked-by: Andreas Larsson <andreas@gaisler.com> [sparc] Acked-by: David Hildenbrand (Arm) <david@kernel.org> Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: "Borislav Petkov (AMD)" <bp@alien8.de> Cc: David S. Miller <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-26kbuild: Split .modinfo out from ELF_DETAILSNathan Chancellor
Commit 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") added .modinfo to ELF_DETAILS while removing it from COMMON_DISCARDS, as it was needed in vmlinux.unstripped and ELF_DETAILS was present in all architecture specific vmlinux linker scripts. While this shuffle is fine for vmlinux, ELF_DETAILS and COMMON_DISCARDS may be used by other linker scripts, such as the s390 and x86 compressed boot images, which may not expect to have a .modinfo section. In certain circumstances, this could result in a bootloader failing to load the compressed kernel [1]. Commit ddc6cbef3ef1 ("s390/boot/vmlinux.lds.S: Ensure bzImage ends with SecureBoot trailer") recently addressed this for the s390 bzImage but the same bug remains for arm, parisc, and x86. The presence of .modinfo in the x86 bzImage was the root cause of the issue worked around with commit d50f21091358 ("kbuild: align modinfo section for Secureboot Authenticode EDK2 compat"). misc.c in arch/x86/boot/compressed includes lib/decompress_unzstd.c, which in turn includes lib/xxhash.c and its MODULE_LICENSE / MODULE_DESCRIPTION macros due to the STATIC definition. Split .modinfo out from ELF_DETAILS into its own macro and handle it in all vmlinux linker scripts. Discard .modinfo in the places where it was previously being discarded from being in COMMON_DISCARDS, as it has never been necessary in those uses. Cc: stable@vger.kernel.org Fixes: 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") Reported-by: Ed W <lists@wildgooses.com> Closes: https://lore.kernel.org/587f25e0-a80e-46a5-9f01-87cb40cfa377@wildgooses.com/ [1] Tested-by: Ed W <lists@wildgooses.com> # x86_64 Link: https://patch.msgid.link/20260225-separate-modinfo-from-elf-details-v1-1-387ced6baf4b@kernel.org Signed-off-by: Nathan Chancellor <nathan@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>
2026-02-12Merge tag 'mm-stable-2026-02-11-19-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "powerpc/64s: do not re-activate batched TLB flush" makes arch_{enter|leave}_lazy_mmu_mode() nest properly (Alexander Gordeev) It adds a generic enter/leave layer and switches architectures to use it. Various hacks were removed in the process. - "zram: introduce compressed data writeback" implements data compression for zram writeback (Richard Chang and Sergey Senozhatsky) - "mm: folio_zero_user: clear page ranges" adds clearing of contiguous page ranges for hugepages. Large improvements during demand faulting are demonstrated (David Hildenbrand) - "memcg cleanups" tidies up some memcg code (Chen Ridong) - "mm/damon: introduce {,max_}nr_snapshots and tracepoint for damos stats" improves DAMOS stat's provided information, deterministic control, and readability (SeongJae Park) - "selftests/mm: hugetlb cgroup charging: robustness fixes" fixes a few issues in the hugetlb cgroup charging selftests (Li Wang) - "Fix va_high_addr_switch.sh test failure - again" addresses several issues in the va_high_addr_switch test (Chunyu Hu) - "mm/damon/tests/core-kunit: extend existing test scenarios" improves the KUnit test coverage for DAMON (Shu Anzai) - "mm/khugepaged: fix dirty page handling for MADV_COLLAPSE" fixes a glitch in khugepaged which was causing madvise(MADV_COLLAPSE) to transiently return -EAGAIN (Shivank Garg) - "arch, mm: consolidate hugetlb early reservation" reworks and consolidates a pile of straggly code related to reservation of hugetlb memory from bootmem and creation of CMA areas for hugetlb (Mike Rapoport) - "mm: clean up anon_vma implementation" cleans up the anon_vma implementation in various ways (Lorenzo Stoakes) - "tweaks for __alloc_pages_slowpath()" does a little streamlining of the page allocator's slowpath code (Vlastimil Babka) - "memcg: separate private and public ID namespaces" cleans up the memcg ID code and prevents the internal-only private IDs from being exposed to userspace (Shakeel Butt) - "mm: hugetlb: allocate frozen gigantic folio" cleans up the allocation of frozen folios and avoids some atomic refcount operations (Kefeng Wang) - "mm/damon: advance DAMOS-based LRU sorting" improves DAMOS's movement of memory betewwn the active and inactive LRUs and adds auto-tuning of the ratio-based quotas and of monitoring intervals (SeongJae Park) - "Support page table check on PowerPC" makes CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc (Andrew Donnellan) - "nodemask: align nodes_and{,not} with underlying bitmap ops" makes nodes_and() and nodes_andnot() propagate the return values from the underlying bit operations, enabling some cleanup in calling code (Yury Norov) - "mm/damon: hide kdamond and kdamond_lock from API callers" cleans up some DAMON internal interfaces (SeongJae Park) - "mm/khugepaged: cleanups and scan limit fix" does some cleanup work in khupaged and fixes a scan limit accounting issue (Shivank Garg) - "mm: balloon infrastructure cleanups" goes to town on the balloon infrastructure and its page migration function. Mainly cleanups, also some locking simplification (David Hildenbrand) - "mm/vmscan: add tracepoint and reason for kswapd_failures reset" adds additional tracepoints to the page reclaim code (Jiayuan Chen) - "Replace wq users and add WQ_PERCPU to alloc_workqueue() users" is part of Marco's kernel-wide migration from the legacy workqueue APIs over to the preferred unbound workqueues (Marco Crivellari) - "Various mm kselftests improvements/fixes" provides various unrelated improvements/fixes for the mm kselftests (Kevin Brodsky) - "mm: accelerate gigantic folio allocation" greatly speeds up gigantic folio allocation, mainly by avoiding unnecessary work in pfn_range_valid_contig() (Kefeng Wang) - "selftests/damon: improve leak detection and wss estimation reliability" improves the reliability of two of the DAMON selftests (SeongJae Park) - "mm/damon: cleanup kdamond, damon_call(), damos filter and DAMON_MIN_REGION" does some cleanup work in the core DAMON code (SeongJae Park) - "Docs/mm/damon: update intro, modules, maintainer profile, and misc" performs maintenance work on the DAMON documentation (SeongJae Park) - "mm: add and use vma_assert_stabilised() helper" refactors and cleans up the core VMA code. The main aim here is to be able to use the mmap write lock's lockdep state to perform various assertions regarding the locking which the VMA code requires (Lorenzo Stoakes) - "mm, swap: swap table phase II: unify swapin use" removes some old swap code (swap cache bypassing and swap synchronization) which wasn't working very well. Various other cleanups and simplifications were made. The end result is a 20% speedup in one benchmark (Kairui Song) - "enable PT_RECLAIM on more 64-bit architectures" makes PT_RECLAIM available on 64-bit alpha, loongarch, mips, parisc, and um. Various cleanups were performed along the way (Qi Zheng) * tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (325 commits) mm/memory: handle non-split locks correctly in zap_empty_pte_table() mm: move pte table reclaim code to memory.c mm: make PT_RECLAIM depends on MMU_GATHER_RCU_TABLE_FREE mm: convert __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config um: mm: enable MMU_GATHER_RCU_TABLE_FREE parisc: mm: enable MMU_GATHER_RCU_TABLE_FREE mips: mm: enable MMU_GATHER_RCU_TABLE_FREE LoongArch: mm: enable MMU_GATHER_RCU_TABLE_FREE alpha: mm: enable MMU_GATHER_RCU_TABLE_FREE mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h mm/damon/stat: remove __read_mostly from memory_idle_ms_percentiles zsmalloc: make common caches global mm: add SPDX id lines to some mm source files mm/zswap: use %pe to print error pointers mm/vmscan: use %pe to print error pointers mm/readahead: fix typo in comment mm: khugepaged: fix NR_FILE_PAGES and NR_SHMEM in collapse_file() mm: refactor vma_map_pages to use vm_insert_pages mm/damon: unify address range representation with damon_addr_range mm/cma: replace snprintf with strscpy in cma_new_area ...
2026-01-30nios2: uapi: Remove custom asm/swab.h from UAPIThomas Weißschuh
UAPI headers are not supposed to leak references to kconfig symbols. They are undefined there in any case. As all actual definitions of this header are guarded behind a kconfig symbol, for userspace the header is always identical to its asm-generic variant. Make the custom UAPI header a kernel-internal one, so the leaks of kconfig symbols are fixed and userspace will instead use asm-generic/swab.h directly. Suggested-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/lkml/93c55086-931a-4282-a94c-de4954047fa9@app.fastmail.com/ Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2026-01-26arch, mm: consolidate initialization of nodes, zones and memory mapMike Rapoport (Microsoft)
To initialize node, zone and memory map data structures every architecture calls free_area_init() during setup_arch() and passes it an array of zone limits. Beside code duplication it creates "interesting" ordering cases between allocation and initialization of hugetlb and the memory map. Some architectures allocate hugetlb pages very early in setup_arch() in certain cases, some only create hugetlb CMA areas in setup_arch() and sometimes hugetlb allocations happen mm_core_init(). With arch_zone_limits_init() helper available now on all architectures it is no longer necessary to call free_area_init() from architecture setup code. Rather core MM initialization can call arch_zone_limits_init() in a single place. This allows to unify ordering of hugetlb vs memory map allocation and initialization. Remove the call to free_area_init() from architecture specific code and place it in a new mm_core_init_early() function that is called immediately after setup_arch(). After this refactoring it is possible to consolidate hugetlb allocations and eliminate differences in ordering of hugetlb and memory map initialization among different architectures. As the first step of this consolidation move hugetlb_bootmem_alloc() to mm_core_early_init(). Link: https://lkml.kernel.org/r/20260111082105.290734-24-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alex Shi <alexs@kernel.org> Cc: Andreas Larsson <andreas@gaisler.com> Cc: "Borislav Petkov (AMD)" <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Hildenbrand <david@kernel.org> Cc: David S. Miller <davem@davemloft.net> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Klara Modin <klarasmodin@gmail.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Pratyush Yadav <pratyush@kernel.org> Cc: Richard Weinberger <richard@nod.at> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26nios2: introduce arch_zone_limits_init()Mike Rapoport (Microsoft)
Move calculations of zone limits to a dedicated arch_zone_limits_init() function. Later MM core will use this function as an architecture specific callback during nodes and zones initialization and thus there won't be a need to call free_area_init() from every architecture. Link: https://lkml.kernel.org/r/20260111082105.290734-13-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alex Shi <alexs@kernel.org> Cc: Andreas Larsson <andreas@gaisler.com> Cc: "Borislav Petkov (AMD)" <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Hildenbrand <david@kernel.org> Cc: David S. Miller <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Klara Modin <klarasmodin@gmail.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Pratyush Yadav <pratyush@kernel.org> Cc: Richard Weinberger <richard@nod.at> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20treewide: provide a generic clear_user_page() variantDavid Hildenbrand
Patch series "mm: folio_zero_user: clear page ranges", v11. This series adds clearing of contiguous page ranges for hugepages. The series improves on the current discontiguous clearing approach in two ways: - clear pages in a contiguous fashion. - use batched clearing via clear_pages() wherever exposed. The first is useful because it allows us to make much better use of hardware prefetchers. The second, enables advertising the real extent to the processor. Where specific instructions support it (ex. string instructions on x86; "mops" on arm64 etc), a processor can optimize based on this because, instead of seeing a sequence of 8-byte stores, or a sequence of 4KB pages, it sees a larger unit being operated on. For instance, AMD Zen uarchs (for extents larger than LLC-size) switch to a mode where they start eliding cacheline allocation. This is helpful not just because it results in higher bandwidth, but also because now the cache is not evicting useful cachelines and replacing them with zeroes. Demand faulting a 64GB region shows performance improvement: $ perf bench mem mmap -p $pg-sz -f demand -s 64GB -l 5 baseline +series (GBps +- %stdev) (GBps +- %stdev) pg-sz=2MB 11.76 +- 1.10% 25.34 +- 1.18% [*] +115.47% preempt=* pg-sz=1GB 24.85 +- 2.41% 39.22 +- 2.32% + 57.82% preempt=none|voluntary pg-sz=1GB (similar) 52.73 +- 0.20% [#] +112.19% preempt=full|lazy [*] This improvement is because switching to sequential clearing allows the hardware prefetchers to do a much better job. [#] For pg-sz=1GB a large part of the improvement is because of the cacheline elision mentioned above. preempt=full|lazy improves upon that because, not needing explicit invocations of cond_resched() to ensure reasonable preemption latency, it can clear the full extent as a single unit. In comparison the maximum extent used for preempt=none|voluntary is PROCESS_PAGES_NON_PREEMPT_BATCH (32MB). When provided the full extent the processor forgoes allocating cachelines on this path almost entirely. (The hope is that eventually, in the fullness of time, the lazy preemption model will be able to do the same job that none or voluntary models are used for, allowing us to do away with cond_resched().) Raghavendra also tested previous version of the series on AMD Genoa and sees similar improvement [1] with preempt=lazy. $ perf bench mem map -p $page-size -f populate -s 64GB -l 10 base patched change pg-sz=2MB 12.731939 GB/sec 26.304263 GB/sec 106.6% pg-sz=1GB 26.232423 GB/sec 61.174836 GB/sec 133.2% This patch (of 8): Let's drop all variants that effectively map to clear_page() and provide it in a generic variant instead. We'll use the macro clear_user_page to indicate whether an architecture provides it's own variant. Also, clear_user_page() is only called from the generic variant of clear_user_highpage(), so define it only if the architecture does not provide a clear_user_highpage(). And, for simplicity define it in linux/highmem.h. Note that for parisc, clear_page() and clear_user_page() map to clear_page_asm(), so we can just get rid of the custom clear_user_page() implementation. There is a clear_user_page_asm() function on parisc, that seems to be unused. Not sure what's up with that. Link: https://lkml.kernel.org/r/20260107072009.1615991-1-ankur.a.arora@oracle.com Link: https://lkml.kernel.org/r/20260107072009.1615991-2-ankur.a.arora@oracle.com Signed-off-by: David Hildenbrand <david@redhat.com> Co-developed-by: Ankur Arora <ankur.a.arora@oracle.com> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ankur Arora <ankur.a.arora@oracle.com> Cc: "Borislav Petkov (AMD)" <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Hildenbrand <david@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Konrad Rzessutek Wilk <konrad.wilk@oracle.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com> Cc: Li Zhe <lizhe.67@bytedance.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Raghavendra K T <raghavendra.kt@amd.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-12-08arch/nios2: replace "__auto_type" and adjacent equivalent with "auto"H. Peter Anvin
Replace uses of "__auto_type" in arch/nios2/include/asm/uaccess.h with "auto", and equivalently convert an adjacent cast to the analogous form. Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
2025-11-21serial: drop SERIAL_8250_DEPRECATED_OPTIONSJiri Slaby (SUSE)
In 3.7, 8250 was unintentionally renamed to 8250_core. This happened in the commit 835d844d1a28 (8250_pnp: do pnp probe before legacy probe). This made 8250.<xxxx> module options effectively defunct. Instead, 8250_core.<xxxx> worked. In 3.9, the commit f2b8dfd9e480 (serial: 8250: Keep 8250.<xxxx> module options functional after driver rename) made the original options work again by introducing a hack. Later in 3.9, the commit 9196d8acd7f9 (TTY: 8250, revert module name change) changed the module name back to 8250 (from 8250_core). Since then, the hack was there to support the transient 8250_core.<xxxx> options. Those were present only in the 3.7..3.9 range. These transient options were deprecated by 9326b047e4fd (TTY: 8250, deprecated 8250_core.* options) in v3.9 too. Now, after those 12 years, it is time to get rid of this hack completely. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://patch.msgid.link/20251119092457.826789-4-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 'sched-core-2025-09-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Core scheduler changes: - Make migrate_{en,dis}able() inline, to improve performance (Menglong Dong) - Move STDL_INIT() functions out-of-line (Peter Zijlstra) - Unify the SCHED_{SMT,CLUSTER,MC} Kconfig (Peter Zijlstra) Fair scheduling: - Defer throttling to when tasks exit to user-space, to reduce the chance & impact of throttle-preemption with held locks and other resources (Aaron Lu, Valentin Schneider) - Get rid of sched_domains_curr_level hack for tl->cpumask(), as the warning was getting triggered on certain topologies (Peter Zijlstra) Misc cleanups & fixes: - Header cleanups (Menglong Dong) - Fix race in push_dl_task() (Harshit Agarwal)" * tag 'sched-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix some typos in include/linux/preempt.h sched: Make migrate_{en,dis}able() inline rcu: Replace preempt.h with sched.h in include/linux/rcupdate.h arch: Add the macro COMPILE_OFFSETS to all the asm-offsets.c sched/fair: Do not balance task to a throttled cfs_rq sched/fair: Do not special case tasks in throttled hierarchy sched/fair: update_cfs_group() for throttled cfs_rqs sched/fair: Propagate load for throttled cfs_rq sched/fair: Get rid of throttled_lb_pair() sched/fair: Task based throttle time accounting sched/fair: Switch to task based throttle model sched/fair: Implement throttle task work and related helpers sched/fair: Add related data structure for task based throttle sched: Unify the SCHED_{SMT,CLUSTER,MC} Kconfig sched: Move STDL_INIT() functions out-of-line sched/fair: Get rid of sched_domains_curr_level hack for tl->cpumask() sched/deadline: Fix race in push_dl_task()
2025-09-29Merge tag 'nios2_update_for_v6.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux Pull NIOS2 updates from Dinh Nguyen: - Replace __ASSEMBLY__ with __ASSEMBLER__ in headers - Set memblock.current_limit when setting pfn limits * tag 'nios2_update_for_v6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux: nios2: ensure that memblock.current_limit is set when setting pfn limits nios2: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers nios2: Replace __ASSEMBLY__ with __ASSEMBLER__ in uapi headers
2025-09-25arch: Add the macro COMPILE_OFFSETS to all the asm-offsets.cMenglong Dong
The include/generated/asm-offsets.h is generated in Kbuild during compiling from arch/SRCARCH/kernel/asm-offsets.c. When we want to generate another similar offset header file, circular dependency can happen. For example, we want to generate a offset file include/generated/test.h, which is included in include/sched/sched.h. If we generate asm-offsets.h first, it will fail, as include/sched/sched.h is included in asm-offsets.c and include/generated/test.h doesn't exist; If we generate test.h first, it can't success neither, as include/generated/asm-offsets.h is included by it. In x86_64, the macro COMPILE_OFFSETS is used to avoid such circular dependency. We can generate asm-offsets.h first, and if the COMPILE_OFFSETS is defined, we don't include the "generated/test.h". And we define the macro COMPILE_OFFSETS for all the asm-offsets.c for this purpose. Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2025-09-13mm: introduce memdesc_flags_tMatthew Wilcox (Oracle)
Patch series "Add and use memdesc_flags_t". At some point struct page will be separated from struct slab and struct folio. This is a step towards that by introducing a type for the 'flags' word of all three structures. This gives us a certain amount of type safety by establishing that some of these unsigned longs are different from other unsigned longs in that they contain things like node ID, section number and zone number in the upper bits. That lets us have functions that can be easily called by anyone who has a slab, folio or page (but not easily by anyone else) to get the node or zone. There's going to be some unusual merge problems with this as some odd bits of the kernel decide they want to print out the flags value or something similar by writing page->flags and now they'll need to write page->flags.f instead. That's most of the churn here. Maybe we should be removing these things from the debug output? This patch (of 11): Wrap the unsigned long flags in a typedef. In upcoming patches, this will provide a strong hint that you can't just pass a random unsigned long to functions which take this as an argument. [willy@infradead.org: s/flags/flags.f/ in several architectures] Link: https://lkml.kernel.org/r/aKMgPRLD-WnkPxYm@casper.infradead.org [nicola.vetrini@gmail.com: mips: fix compilation error] Link: https://lore.kernel.org/lkml/CA+G9fYvkpmqGr6wjBNHY=dRp71PLCoi2341JxOudi60yqaeUdg@mail.gmail.com/ Link: https://lkml.kernel.org/r/20250825214245.1838158-1-nicola.vetrini@gmail.com Link: https://lkml.kernel.org/r/20250805172307.1302730-1-willy@infradead.org Link: https://lkml.kernel.org/r/20250805172307.1302730-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Zi Yan <ziy@nvidia.com> Cc: Shakeel Butt <shakeel.butt@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-01nios2: implement architecture-specific portion of sys_clone3Simon Schuster
This commit adds the sys_clone3 entry point for nios2. An architecture-specific wrapper (__sys_clone3) is required to save and restore additional registers to the kernel stack via SAVE_SWITCH_STACK and RESTORE_SWITCH_STACK. Signed-off-by: Simon Schuster <schuster.simon@siemens-energy.com> Link: https://lore.kernel.org/20250901-nios2-implement-clone3-v2-4-53fcf5577d57@siemens-energy.com Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-01arch: copy_thread: pass clone_flags as u64Simon 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 the copy_thread function that is called from copy_process 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-v2-3-53fcf5577d57@siemens-energy.com Fixes: c5febea0956fd387 ("fork: Pass struct kernel_clone_args into copy_thread") Acked-by: Guo Ren (Alibaba Damo Academy) <guoren@kernel.org> Acked-by: Andreas Larsson <andreas@gaisler.com> # sparc Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-25nios2: ensure that memblock.current_limit is set when setting pfn limitsSimon Schuster
On nios2, with CONFIG_FLATMEM set, the kernel relies on memblock_get_current_limit() to determine the limits of mem_map, in particular for max_low_pfn. Unfortunately, memblock.current_limit is only default initialized to MEMBLOCK_ALLOC_ANYWHERE at this point of the bootup, potentially leading to situations where max_low_pfn can erroneously exceed the value of max_pfn and, thus, the valid range of available DRAM. This can in turn cause kernel-level paging failures, e.g.: [ 76.900000] Unable to handle kernel paging request at virtual address 20303000 [ 76.900000] ea = c0080890, ra = c000462c, cause = 14 [ 76.900000] Kernel panic - not syncing: Oops [ 76.900000] ---[ end Kernel panic - not syncing: Oops ]--- This patch fixes this by pre-calculating memblock.current_limit based on the upper limits of the available memory ranges via adjust_lowmem_bounds, a simplified version of the equivalent implementation within the arm architecture. Signed-off-by: Simon Schuster <schuster.simon@siemens-energy.com> Signed-off-by: Andreas Oetken <andreas.oetken@siemens-energy.com> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
2025-08-25nios2: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headersThomas Huth
While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's standardize on the __ASSEMBLER__ macro that is provided by the compilers now. This is a completely mechanical patch (done with a simple "sed -i" statement). Cc: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
2025-08-25nios2: Replace __ASSEMBLY__ with __ASSEMBLER__ in uapi headersThomas Huth
__ASSEMBLY__ is only defined by the Makefile of the kernel, so this is not really useful for uapi headers (unless the userspace Makefile defines it, too). Let's switch to __ASSEMBLER__ which gets set automatically by the compiler when compiling assembly code. This is a completely mechanical patch (done with a simple "sed -i" statement). Cc: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
2025-07-14nios2: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note namesDave Martin
Instead of having the core code guess the note name for each regset, use USER_REGSET_NOTE_TYPE() to pick the correct name from elf.h. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <kees@kernel.org> Cc: Akihiko Odaki <akihiko.odaki@daynix.com> Reviewed-by: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp> Link: https://lore.kernel.org/r/20250701135616.29630-13-Dave.Martin@arm.com Signed-off-by: Kees Cook <kees@kernel.org>
2025-06-11mm: pgtable: fix pte_swp_exclusiveMagnus Lindholm
Make pte_swp_exclusive return bool instead of int. This will better reflect how pte_swp_exclusive is actually used in the code. This fixes swap/swapoff problems on Alpha due pte_swp_exclusive not returning correct values when _PAGE_SWP_EXCLUSIVE bit resides in upper 32-bits of PTE (like on alpha). Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Magnus Lindholm <linmag7@gmail.com> Cc: Sam James <sam@gentoo.org> Link: https://lore.kernel.org/lkml/20250218175735.19882-2-linmag7@gmail.com/ Link: https://lore.kernel.org/lkml/20250602041118.GA2675383@ZenIV/ [ Applied as the 'sed' script Al suggested - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-06-07Merge tag 'kbuild-v6.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Add support for the EXPORT_SYMBOL_GPL_FOR_MODULES() macro, which exports a symbol only to specified modules - Improve ABI handling in gendwarfksyms - Forcibly link lib-y objects to vmlinux even if CONFIG_MODULES=n - Add checkers for redundant or missing <linux/export.h> inclusion - Deprecate the extra-y syntax - Fix a genksyms bug when including enum constants from *.symref files * tag 'kbuild-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (28 commits) genksyms: Fix enum consts from a reference affecting new values arch: use always-$(KBUILD_BUILTIN) for vmlinux.lds kbuild: set y instead of 1 to KBUILD_{BUILTIN,MODULES} efi/libstub: use 'targets' instead of extra-y in Makefile module: make __mod_device_table__* symbols static scripts/misc-check: check unnecessary #include <linux/export.h> when W=1 scripts/misc-check: check missing #include <linux/export.h> when W=1 scripts/misc-check: add double-quotes to satisfy shellcheck kbuild: move W=1 check for scripts/misc-check to top-level Makefile scripts/tags.sh: allow to use alternative ctags implementation kconfig: introduce menu type enum docs: symbol-namespaces: fix reST warning with literal block kbuild: link lib-y objects to vmlinux forcibly even when CONFIG_MODULES=n tinyconfig: enable CONFIG_LD_DEAD_CODE_DATA_ELIMINATION docs/core-api/symbol-namespaces: drop table of contents and section numbering modpost: check forbidden MODULE_IMPORT_NS("module:") at compile time kbuild: move kbuild syntax processing to scripts/Makefile.build Makefile: remove dependency on archscripts for header installation Documentation/kbuild: Add new gendwarfksyms kABI rules Documentation/kbuild: Drop section numbers ...
2025-06-07arch: use always-$(KBUILD_BUILTIN) for vmlinux.ldsMasahiro Yamada
The extra-y syntax is deprecated. Instead, use always-$(KBUILD_BUILTIN), which behaves equivalently. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Johannes Berg <johannes@sipsolutions.net> Reviewed-by: Nicolas Schier <n.schier@avm.de>
2025-05-31Merge tag 'mm-stable-2025-05-31-14-50' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of creating a pte which addresses the first page in a folio and reduces the amount of plumbing which architecture must implement to provide this. - "Misc folio patches for 6.16" from Matthew Wilcox is a shower of largely unrelated folio infrastructure changes which clean things up and better prepare us for future work. - "memory,x86,acpi: hotplug memory alignment advisement" from Gregory Price adds early-init code to prevent x86 from leaving physical memory unused when physical address regions are not aligned to memory block size. - "mm/compaction: allow more aggressive proactive compaction" from Michal Clapinski provides some tuning of the (sadly, hard-coded (more sadly, not auto-tuned)) thresholds for our invokation of proactive compaction. In a simple test case, the reduction of a guest VM's memory consumption was dramatic. - "Minor cleanups and improvements to swap freeing code" from Kemeng Shi provides some code cleaups and a small efficiency improvement to this part of our swap handling code. - "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin adds the ability for a ptracer to modify syscalls arguments. At this time we can alter only "system call information that are used by strace system call tampering, namely, syscall number, syscall arguments, and syscall return value. This series should have been incorporated into mm.git's "non-MM" branch, but I goofed. - "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl against /proc/pid/pagemap. This permits CRIU to more efficiently get at the info about guard regions. - "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan implements that fix. No runtime effect is expected because validate_page_before_insert() happens to fix up this error. - "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David Hildenbrand basically brings uprobe text poking into the current decade. Remove a bunch of hand-rolled implementation in favor of using more current facilities. - "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman Khandual provides enhancements and generalizations to the pte dumping code. This might be needed when 128-bit Page Table Descriptors are enabled for ARM. - "Always call constructor for kernel page tables" from Kevin Brodsky ensures that the ctor/dtor is always called for kernel pgtables, as it already is for user pgtables. This permits the addition of more functionality such as "insert hooks to protect page tables". This change does result in various architectures performing unnecesary work, but this is fixed up where it is anticipated to occur. - "Rust support for mm_struct, vm_area_struct, and mmap" from Alice Ryhl adds plumbing to permit Rust access to core MM structures. - "fix incorrectly disallowed anonymous VMA merges" from Lorenzo Stoakes takes advantage of some VMA merging opportunities which we've been missing for 15 years. - "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from SeongJae Park optimizes process_madvise()'s TLB flushing. Instead of flushing each address range in the provided iovec, we batch the flushing across all the iovec entries. The syscall's cost was approximately halved with a microbenchmark which was designed to load this particular operation. - "Track node vacancy to reduce worst case allocation counts" from Sidhartha Kumar makes the maple tree smarter about its node preallocation. stress-ng mmap performance increased by single-digit percentages and the amount of unnecessarily preallocated memory was dramaticelly reduced. - "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes a few unnecessary things which Baoquan noted when reading the code. - ""Enhance sysfs handling for memory hotplug in weighted interleave" from Rakie Kim "enhances the weighted interleave policy in the memory management subsystem by improving sysfs handling, fixing memory leaks, and introducing dynamic sysfs updates for memory hotplug support". Fixes things on error paths which we are unlikely to hit. - "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory" from SeongJae Park introduces new DAMOS quota goal metrics which eliminate the manual tuning which is required when utilizing DAMON for memory tiering. - "mm/vmalloc.c: code cleanup and improvements" from Baoquan He provides cleanups and small efficiency improvements which Baoquan found via code inspection. - "vmscan: enforce mems_effective during demotion" from Gregory Price changes reclaim to respect cpuset.mems_effective during demotion when possible. because presently, reclaim explicitly ignores cpuset.mems_effective when demoting, which may cause the cpuset settings to violated. This is useful for isolating workloads on a multi-tenant system from certain classes of memory more consistently. - "Clean up split_huge_pmd_locked() and remove unnecessary folio pointers" from Gavin Guo provides minor cleanups and efficiency gains in in the huge page splitting and migrating code. - "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache for `struct mem_cgroup', yielding improved memory utilization. - "add max arg to swappiness in memory.reclaim and lru_gen" from Zhongkun He adds a new "max" argument to the "swappiness=" argument for memory.reclaim MGLRU's lru_gen. This directs proactive reclaim to reclaim from only anon folios rather than file-backed folios. - "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the first step on the path to permitting the kernel to maintain existing VMs while replacing the host kernel via file-based kexec. At this time only memblock's reserve_mem is preserved. - "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides and uses a smarter way of looping over a pfn range. By skipping ranges of invalid pfns. - "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning when a task is pinned a single NUMA mode. Dramatic performance benefits were seen in some real world cases. - "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank Garg addresses a warning which occurs during memory compaction when using JFS. - "move all VMA allocation, freeing and duplication logic to mm" from Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more appropriate mm/vma.c. - "mm, swap: clean up swap cache mapping helper" from Kairui Song provides code consolidation and cleanups related to the folio_index() function. - "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that. - "memcg: Fix test_memcg_min/low test failures" from Waiman Long addresses some bogus failures which are being reported by the test_memcontrol selftest. - "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo Stoakes commences the deprecation of file_operations.mmap() in favor of the new file_operations.mmap_prepare(). The latter is more restrictive and prevents drivers from messing with things in ways which, amongst other problems, may defeat VMA merging. - "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples the per-cpu memcg charge cache from the objcg's one. This is a step along the way to making memcg and objcg charging NMI-safe, which is a BPF requirement. - "mm/damon: minor fixups and improvements for code, tests, and documents" from SeongJae Park is yet another batch of miscellaneous DAMON changes. Fix and improve minor problems in code, tests and documents. - "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg stats to be irq safe. Another step along the way to making memcg charging and stats updates NMI-safe, a BPF requirement. - "Let unmap_hugepage_range() and several related functions take folio instead of page" from Fan Ni provides folio conversions in the hugetlb code. * tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits) mm: pcp: increase pcp->free_count threshold to trigger free_high mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range() mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page mm/hugetlb: pass folio instead of page to unmap_ref_private() memcg: objcg stock trylock without irq disabling memcg: no stock lock for cpu hot-unplug memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs memcg: make count_memcg_events re-entrant safe against irqs memcg: make mod_memcg_state re-entrant safe against irqs memcg: move preempt disable to callers of memcg_rstat_updated memcg: memcg_rstat_updated re-entrant safe against irqs mm: khugepaged: decouple SHMEM and file folios' collapse selftests/eventfd: correct test name and improve messages alloc_tag: check mem_profiling_support in alloc_tag_init Docs/damon: update titles and brief introductions to explain DAMOS selftests/damon/_damon_sysfs: read tried regions directories in order mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject() mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat() mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs ...
2025-05-28Merge tag 'nios2_updates_for_v6.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux Pull nios2 updates fromDinh Nguyen: - Use strscpy() and simply setup_cpuinfo() - Remove conflicting mappings when flushing tlb entries - Force update_mmu_cache on spurious pagefaults * tag 'nios2_updates_for_v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux: nios2: Replace strcpy() with strscpy() and simplify setup_cpuinfo() nios2: do not introduce conflicting mappings when flushing tlb entries nios2: force update_mmu_cache on spurious tlb-permission--related pagefaults
2025-05-16nios2: Switch to irq_domain_create_linear()Jiri Slaby (SUSE)
irq_domain_add_linear() is going away as being obsolete now. Switch to the preferred irq_domain_create_linear(). That differs in the first parameter: It takes more generic struct fwnode_handle instead of struct device_node. Therefore, of_fwnode_handle() is added around the parameter. Note some of the users can likely use dev->fwnode directly instead of indirect of_fwnode_handle(dev->of_node). But dev->fwnode is not guaranteed to be set for all, so this has to be investigated on case to case basis (by people who can actually test with the HW). Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250319092951.37667-29-jirislaby@kernel.org
2025-05-11syscall.h: introduce syscall_set_nr()Dmitry V. Levin
Similar to syscall_set_arguments() that complements syscall_get_arguments(), introduce syscall_set_nr() that complements syscall_get_nr(). syscall_set_nr() is going to be needed along with syscall_set_arguments() on all HAVE_ARCH_TRACEHOOK architectures to implement PTRACE_SET_SYSCALL_INFO API. Link: https://lkml.kernel.org/r/20250303112020.GD24170@strace.io Signed-off-by: Dmitry V. Levin <ldv@strace.io> Tested-by: Charlie Jenkins <charlie@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Acked-by: Helge Deller <deller@gmx.de> # parisc Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk> # mips Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexey Gladkov (Intel) <legion@kernel.org> Cc: Andreas Larsson <andreas@gaisler.com> Cc: anton ivanov <anton.ivanov@cambridgegreys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Betkov <bp@alien8.de> Cc: Brian Cain <bcain@quicinc.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Zankel <chris@zankel.net> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Davide Berardi <berardi.dav@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Eugene Syromiatnikov <esyr@redhat.com> Cc: Eugene Syromyatnikov <evgsyr@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonas Bonn <jonas@southpole.se> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Naveen N Rao <naveen@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Renzo Davoi <renzo@cs.unibo.it> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russel King <linux@armlinux.org.uk> Cc: Shuah Khan <shuah@kernel.org> Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11syscall.h: add syscall_set_arguments()Dmitry V. Levin
This function is going to be needed on all HAVE_ARCH_TRACEHOOK architectures to implement PTRACE_SET_SYSCALL_INFO API. This partially reverts commit 7962c2eddbfe ("arch: remove unused function syscall_set_arguments()") by reusing some of old syscall_set_arguments() implementations. [nathan@kernel.org: fix compile time fortify checks] Link: https://lkml.kernel.org/r/20250408213131.GA2872426@ax162 Link: https://lkml.kernel.org/r/20250303112009.GC24170@strace.io Signed-off-by: Dmitry V. Levin <ldv@strace.io> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Charlie Jenkins <charlie@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Acked-by: Helge Deller <deller@gmx.de> # parisc Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk> [mips] Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexey Gladkov (Intel) <legion@kernel.org> Cc: Andreas Larsson <andreas@gaisler.com> Cc: anton ivanov <anton.ivanov@cambridgegreys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Betkov <bp@alien8.de> Cc: Brian Cain <bcain@quicinc.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Zankel <chris@zankel.net> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Davide Berardi <berardi.dav@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Eugene Syromiatnikov <esyr@redhat.com> Cc: Eugene Syromyatnikov <evgsyr@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonas Bonn <jonas@southpole.se> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Naveen N Rao <naveen@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Renzo Davoi <renzo@cs.unibo.it> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russel King <linux@armlinux.org.uk> Cc: Shuah Khan <shuah@kernel.org> Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>