kernel/linux.git/arch/microblaze, branch master

mm: change to return bool for ptep_test_and_clear_young()

2026-04-05T20:53:35+00:00

Patch series "change young flag check functions to return bool", v2. This is a cleanup patchset to change all young flag check functions to return bool, as discussed with David in the previous thread[1]. Since callers only care about whether the young flag was set, returning bool makes the intention clearer. No functional changes intended. This patch (of 6): Callers use ptep_test_and_clear_young() to clear the young flag and check whether it was set. Change the return type to bool to make the intention clearer. Link: https://lkml.kernel.org/r/cover.1774075004.git.baolin.wang@linux.alibaba.com Link: https://lkml.kernel.org/r/57e70efa9703d43959aa645246ea3cbdba14fa17.1774075004.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang Reviewed-by: Ritesh Harjani (IBM) Reviewed-by: Lorenzo Stoakes (Oracle) Acked-by: David Hildenbrand (Arm) Cc: Liam Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton

arch, mm: consolidate empty_zero_page

2026-04-05T20:53:01+00:00

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) Acked-by: Helge Deller [parisc] Tested-by: Helge Deller [parisc] Reviewed-by: Christophe Leroy (CS GROUP) Acked-by: Dave Hansen Acked-by: Catalin Marinas Acked-by: Magnus Lindholm [alpha] Acked-by: Dinh Nguyen [nios2] Acked-by: Andreas Larsson [sparc] Acked-by: David Hildenbrand (Arm) Acked-by: Liam R. Howlett Cc: "Borislav Petkov (AMD)" Cc: David S. Miller Cc: Geert Uytterhoeven Cc: Guo Ren Cc: Huacai Chen Cc: Ingo Molnar Cc: Johannes Berg Cc: John Paul Adrian Glaubitz Cc: Lorenzo Stoakes Cc: Madhavan Srinivasan Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Hocko Cc: Michal Simek Cc: Palmer Dabbelt Cc: Richard Weinberger Cc: Russell King Cc: Stafford Horne Cc: Suren Baghdasaryan Cc: Vineet Gupta Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton

Merge tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-02-12T19:32:37+00:00

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 ...

arch, mm: consolidate initialization of nodes, zones and memory map

2026-01-27T04:02:18+00:00

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) Cc: Alexander Gordeev Cc: Alex Shi Cc: Andreas Larsson Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: David Hildenbrand Cc: David S. Miller Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: Huacai Chen Cc: Ingo Molnar Cc: Johannes Berg Cc: John Paul Adrian Glaubitz Cc: Jonathan Corbet Cc: Klara Modin Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Magnus Lindholm Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Hocko Cc: Michal Simek Cc: Muchun Song Cc: Oscar Salvador Cc: Palmer Dabbelt Cc: Pratyush Yadav Cc: Richard Weinberger Cc: "Ritesh Harjani (IBM)" Cc: Russell King Cc: Stafford Horne Cc: Suren Baghdasaryan Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton

microblaze: introduce arch_zone_limits_init()

2026-01-27T04:02:15+00:00

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/20260111082105.290734-11-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Cc: Alexander Gordeev Cc: Alex Shi Cc: Andreas Larsson Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: David Hildenbrand Cc: David S. Miller Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: Huacai Chen Cc: Ingo Molnar Cc: Johannes Berg Cc: John Paul Adrian Glaubitz Cc: Jonathan Corbet Cc: Klara Modin Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Magnus Lindholm Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Hocko Cc: Michal Simek Cc: Muchun Song Cc: Oscar Salvador Cc: Palmer Dabbelt Cc: Pratyush Yadav Cc: Richard Weinberger Cc: "Ritesh Harjani (IBM)" Cc: Russell King Cc: Stafford Horne Cc: Suren Baghdasaryan Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton

rseq: Implement sys_rseq_slice_yield()

2026-01-22T10:11:17+00:00

Provide a new syscall which has the only purpose to yield the CPU after the kernel granted a time slice extension. sched_yield() is not suitable for that because it unconditionally schedules, but the end of the time slice extension is not required to schedule when the task was already preempted. This also allows to have a strict check for termination to catch user space invoking random syscalls including sched_yield() from a time slice extension region. Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Mathieu Desnoyers Acked-by: Arnd Bergmann Link: https://patch.msgid.link/20251215155708.929634896@linutronix.de

treewide: provide a generic clear_user_page() variant

2026-01-21T03:24:39+00:00

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 Co-developed-by: Ankur Arora Signed-off-by: Ankur Arora Cc: Andy Lutomirski Cc: Ankur Arora Cc: "Borislav Petkov (AMD)" Cc: Boris Ostrovsky Cc: David Hildenbrand Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Konrad Rzessutek Wilk Cc: Lance Yang Cc: "Liam R. Howlett" Cc: Li Zhe Cc: Lorenzo Stoakes Cc: Mateusz Guzik Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Mike Rapoport Cc: Peter Zijlstra Cc: Raghavendra K T Cc: Suren Baghdasaryan Cc: Thomas Gleixner Cc: Vlastimil Babka Signed-off-by: Andrew Morton

arch: hookup listns() system call

2025-11-03T16:41:18+00:00

Add the listns() system call to all architectures. Link: https://patch.msgid.link/20251029-work-namespace-nstree-listns-v4-20-2e6f823ebdc0@kernel.org Tested-by: syzbot@syzkaller.appspotmail.com Reviewed-by: Arnd Bergmann Reviewed-by: Jeff Layton Signed-off-by: Christian Brauner

Merge tag 'ext4_for_linus-6.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2025-10-15T14:51:57+00:00

Pull ext4 bug fixes from Ted Ts'o: - Fix regression caused by removing CONFIG_EXT3_FS when testing some very old defconfigs - Avoid a BUG_ON when opening a file on a maliciously corrupted file system - Avoid mm warnings when freeing a very large orphan file metadata - Avoid a theoretical races between metadata writeback and checkpoints (it's very hard to hit in practice, since the race requires that the writeback take a very long time) * tag 'ext4_for_linus-6.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: Use CONFIG_EXT4_FS instead of CONFIG_EXT3_FS in all of the defconfigs ext4: free orphan info with kvfree ext4: detect invalid INLINE_DATA + EXTENTS flag combination ext4, doc: fix and improve directory hash tree description ext4: wait for ongoing I/O to complete before freeing blocks jbd2: ensure that all ongoing I/O complete before freeing blocks

Use CONFIG_EXT4_FS instead of CONFIG_EXT3_FS in all of the defconfigs

2025-10-14T01:50:40+00:00

Commit d6ace46c82fd ("ext4: remove obsolete EXT3 config options") removed the obsolete EXT3_CONFIG options, since it had been over a decade since fs/ext3 had been removed. Unfortunately, there were a number of defconfigs that still used CONFIG_EXT3_FS which the cleanup commit didn't fix up. This led to a large number of defconfig test builds to fail. Oops. Fixes: d6ace46c82fd ("ext4: remove obsolete EXT3 config options") Signed-off-by: Theodore Ts'o