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6 daysMerge tag 'mm-stable-2025-12-03-21-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki) Rework the vmalloc() code to support non-blocking allocations (GFP_ATOIC, GFP_NOWAIT) "ksm: fix exec/fork inheritance" (xu xin) Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited across fork/exec "mm/zswap: misc cleanup of code and documentations" (SeongJae Park) Some light maintenance work on the zswap code "mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira) Enhance the /sys/kernel/debug/page_owner debug feature by adding unique identifiers to differentiate the various stack traces so that userspace monitoring tools can better match stack traces over time "mm/page_alloc: pcp->batch cleanups" (Joshua Hahn) Minor alterations to the page allocator's per-cpu-pages feature "Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra) Address a scalability issue in userfaultfd's UFFDIO_MOVE operation "kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov) "drivers/base/node: fold node register and unregister functions" (Donet Tom) Clean up the NUMA node handling code a little "mm: some optimizations for prot numa" (Kefeng Wang) Cleanups and small optimizations to the NUMA allocation hinting code "mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn) Address long lock hold times at boot on large machines. These were causing (harmless) softlockup warnings "optimize the logic for handling dirty file folios during reclaim" (Baolin Wang) Remove some now-unnecessary work from page reclaim "mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park) Enhance the DAMOS auto-tuning feature "mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan) Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace configuration "expand mmap_prepare functionality, port more users" (Lorenzo Stoakes) Enhance the new(ish) file_operations.mmap_prepare() method and port additional callsites from the old ->mmap() over to ->mmap_prepare() "Fix stale IOTLB entries for kernel address space" (Lu Baolu) Fix a bug (and possible security issue on non-x86) in the IOMMU code. In some situations the IOMMU could be left hanging onto a stale kernel pagetable entry "mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang) Clean up and optimize the folio splitting code "mm, swap: misc cleanup and bugfix" (Kairui Song) Some cleanups and a minor fix in the swap discard code "mm/damon: misc documentation fixups" (SeongJae Park) "mm/damon: support pin-point targets removal" (SeongJae Park) Permit userspace to remove a specific monitoring target in the middle of the current targets list "mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo) A couple of cleanups related to mm header file inclusion "mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He) improve the selection of swap devices for NUMA machines "mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista) Change the memory block labels from macros to enums so they will appear in kernel debug info "ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes) Address an inefficiency when KSM unmerges an address range "mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park) Fix leaks and unhandled malloc() failures in DAMON userspace unit tests "some cleanups for pageout()" (Baolin Wang) Clean up a couple of minor things in the page scanner's writeback-for-eviction code "mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu) Move hugetlb's sysfs/sysctl handling code into a new file "introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes) Make the VMA guard regions available in /proc/pid/smaps and improves the mergeability of guarded VMAs "mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes) Reduce mmap lock contention for callers performing VMA guard region operations "vma_start_write_killable" (Matthew Wilcox) Start work on permitting applications to be killed when they are waiting on a read_lock on the VMA lock "mm/damon/tests: add more tests for online parameters commit" (SeongJae Park) Add additional userspace testing of DAMON's "commit" feature "mm/damon: misc cleanups" (SeongJae Park) "make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes) Address the possible loss of a VMA's VM_SOFTDIRTY flag when that VMA is merged with another "mm: support device-private THP" (Balbir Singh) Introduce support for Transparent Huge Page (THP) migration in zone device-private memory "Optimize folio split in memory failure" (Zi Yan) "mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang) Some more cleanups in the folio splitting code "mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes) Clean up our handling of pagetable leaf entries by introducing the concept of 'software leaf entries', of type softleaf_t "reparent the THP split queue" (Muchun Song) Reparent the THP split queue to its parent memcg. This is in preparation for addressing the long-standing "dying memcg" problem, wherein dead memcg's linger for too long, consuming memory resources "unify PMD scan results and remove redundant cleanup" (Wei Yang) A little cleanup in the hugepage collapse code "zram: introduce writeback bio batching" (Sergey Senozhatsky) Improve zram writeback efficiency by introducing batched bio writeback support "memcg: cleanup the memcg stats interfaces" (Shakeel Butt) Clean up our handling of the interrupt safety of some memcg stats "make vmalloc gfp flags usage more apparent" (Vishal Moola) Clean up vmalloc's handling of incoming GFP flags "mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang) Teach soft dirty and userfaultfd write protect tracking to use RISC-V's Svrsw60t59b extension "mm: swap: small fixes and comment cleanups" (Youngjun Park) Fix a small bug and clean up some of the swap code "initial work on making VMA flags a bitmap" (Lorenzo Stoakes) Start work on converting the vma struct's flags to a bitmap, so we stop running out of them, especially on 32-bit "mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park) Address a possible bug in the swap discard code and clean things up a little [ This merge also reverts commit ebb9aeb980e5 ("vfio/nvgrace-gpu: register device memory for poison handling") because it looks broken to me, I've asked for clarification - Linus ] * tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) mm: fix vma_start_write_killable() signal handling mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate mm/swapfile: fix list iteration when next node is removed during discard fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling mm/kfence: add reboot notifier to disable KFENCE on shutdown memcg: remove inc/dec_lruvec_kmem_state helpers selftests/mm/uffd: initialize char variable to Null mm: fix DEBUG_RODATA_TEST indentation in Kconfig mm: introduce VMA flags bitmap type tools/testing/vma: eliminate dependency on vma->__vm_flags mm: simplify and rename mm flags function for clarity mm: declare VMA flags by bit zram: fix a spelling mistake mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity mm/vmscan: skip increasing kswapd_failures when reclaim was boosted pagemap: update BUDDY flag documentation mm: swap: remove scan_swap_map_slots() references from comments mm: swap: change swap_alloc_slow() to void mm, swap: remove redundant comment for read_swap_cache_async mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational ...
2025-11-20memory_hotplug: optimise try_offline_memory_block()Matthew Wilcox (Oracle)
Extract the zone number directly from the page instead of using the page's zone number to look up the zone and asking the zone what its number is. Link: https://lkml.kernel.org/r/20251106201452.2292631-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: David Hildenbrand <david@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16drivers/base/node: fold unregister_node() into unregister_one_node()Donet Tom
unregister_node() is only called from unregister_one_node(). This patch folds unregister_node() into its only caller and renames unregister_one_node() to unregister_node(). This reduces unnecessary indirection and simplifies the code structure. No functional changes are introduced. [donettom@linux.ibm.com: remove extra spaces before @nid and "All"] Link: https://lkml.kernel.org/r/cff01514-9074-4c97-bcf1-d4e3594e48b0@linux.ibm.com Link: https://lkml.kernel.org/r/32b7d5d8f0f30d313c3e1d8798f591459c8746f9.1760097208.git.donettom@linux.ibm.com Signed-off-by: Donet Tom <donettom@linux.ibm.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: SeongJae Park <sj@kernel.org> Cc: Aboorva Devarajan <aboorvad@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Danilo Krummrich <dakr@kernel.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16drivers/base/node: fold register_node() into register_one_node()Donet Tom
Patch series "drivers/base/node: fold node register and unregister functions", v2. The first patch merges register_one_node() and register_node(), leaving a single register_node() function. The second patch merges unregister_one_node() and unregister_node(), leaving a single unregister_node() function. There are no functional changes in these patches. This patch (of 2): register_node() is only called from register_one_node(). This patch folds register_node() into its only caller and renames register_one_node() to register_node(). This reduces unnecessary indirection and simplifies the code structure. No functional changes are introduced. [akpm@linux-foundation.org: fix kerneldoc, per David] Link: https://lkml.kernel.org/r/cover.1760097207.git.donettom@linux.ibm.com Link: https://lkml.kernel.org/r/910853c9dd61f7a2190a56cba101e73e9c6859be.1760097207.git.donettom@linux.ibm.com Signed-off-by: Donet Tom <donettom@linux.ibm.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: SeongJae Park <sj@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Aboorva Devarajan <aboorvad@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Danilo Krummrich <dakr@kernel.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-14mm/memory_hotplug: Remove MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE notifiersSumanth Korikkar
MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE memory notifiers were introduced to prepare the transition of memory to and from a physically accessible state. This enhancement was crucial for implementing the "memmap on memory" feature for s390. With introduction of dynamic (de)configuration of hotpluggable memory, memory can be brought to accessible state before add_memory(). Memory can be brought to inaccessible state before remove_memory(). Hence, there is no need of MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE memory notifiers anymore. This basically reverts commit c5f1e2d18909 ("mm/memory_hotplug: introduce MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE notifiers") Additionally, apply minor adjustments to the function parameters of move_pfn_range_to_zone() and mhp_supports_memmap_on_memory() to ensure compatibility with the latest branch. Acked-by: David Hildenbrand <david@redhat.com> Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-10-03mm/memory_hotplug: activate node before adding new memory blocksHannes Reinecke
The sysfs attributes for memory blocks require the node ID to be set and initialized, so move the node activation before adding new memory blocks. This also has the nice side effect that the BUG_ON() can be converted into a WARN_ON() as we now can handle registration errors. Link: https://lkml.kernel.org/r/20250729064637.51662-3-hare@kernel.org Fixes: b9ff036082cd ("mm/memory_hotplug.c: make add_memory_resource use __try_online_node") Signed-off-by: Hannes Reinecke <hare@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Donet Tom <donettom@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-28mm/memory_hotplug: fix typo 'esecially' -> 'especially'Manish Kumar
Link: https://lkml.kernel.org/r/20250918174528.90879-1-manish1588@gmail.com Signed-off-by: Manish Kumar <manish1588@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-21mm/memremap: remove unused get_dev_pagemap() parameterAlistair Popple
GUP no longer uses get_dev_pagemap(). As it was the only user of the get_dev_pagemap() pgmap caching feature it can be removed. Link: https://lkml.kernel.org/r/20250903225926.34702-2-apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-03mm/memory_hotplug: fix hwpoisoned large folio handling in do_migrate_range()Jinjiang Tu
In do_migrate_range(), the hwpoisoned folio may be large folio, which can't be handled by unmap_poisoned_folio(). I can reproduce this issue in qemu after adding delay in memory_failure() BUG: kernel NULL pointer dereference, address: 0000000000000000 Workqueue: kacpi_hotplug acpi_hotplug_work_fn RIP: 0010:try_to_unmap_one+0x16a/0xfc0 <TASK> rmap_walk_anon+0xda/0x1f0 try_to_unmap+0x78/0x80 ? __pfx_try_to_unmap_one+0x10/0x10 ? __pfx_folio_not_mapped+0x10/0x10 ? __pfx_folio_lock_anon_vma_read+0x10/0x10 unmap_poisoned_folio+0x60/0x140 do_migrate_range+0x4d1/0x600 ? slab_memory_callback+0x6a/0x190 ? notifier_call_chain+0x56/0xb0 offline_pages+0x3e6/0x460 memory_subsys_offline+0x130/0x1f0 device_offline+0xba/0x110 acpi_bus_offline+0xb7/0x130 acpi_scan_hot_remove+0x77/0x290 acpi_device_hotplug+0x1e0/0x240 acpi_hotplug_work_fn+0x1a/0x30 process_one_work+0x186/0x340 Besides, do_migrate_range() may be called between memory_failure set hwpoison flag and isolate the folio from lru, so remove WARN_ON(). In other places, unmap_poisoned_folio() is called when the folio is isolated, obey it in do_migrate_range() too. [david@redhat.com: don't abort offlining, fixed typo, add comment] Link: https://lkml.kernel.org/r/3c214dff-9649-4015-840f-10de0e03ebe4@redhat.com Fixes: b15c87263a69 ("hwpoison, memory_hotplug: allow hwpoisoned pages to be offlined") Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com> Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Luis Chamberalin <mcgrof@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pankaj Raghav <kernel@pankajraghav.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-13mm: rename __PageMovable() to page_has_movable_ops()David Hildenbrand
Let's make it clearer that we are talking about movable_ops pages. While at it, convert a VM_BUG_ON to a VM_WARN_ON_ONCE_PAGE. Link: https://lkml.kernel.org/r/20250704102524.326966-17-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Brendan Jackman <jackmanb@google.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Christian Brauner <brauner@kernel.org> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Eugenio Pé rez <eperezma@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Gregory Price <gourry@gourry.net> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Jan Kara <jack@suse.cz> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jason Wang <jasowang@redhat.com> Cc: Jerrin Shaji George <jerrin.shaji-george@broadcom.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Mathew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Rik van Riel <riel@surriel.com> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Cc: xu xin <xu.xin16@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-13mm/page_isolation: remove migratetype parameter from more functionsZi Yan
migratetype is no longer overwritten during pageblock isolation, start_isolate_page_range(), has_unmovable_pages(), and set_migratetype_isolate() no longer need which migratetype to restore during isolation failure. For has_unmoable_pages(), it needs to know if the isolation is for CMA allocation, so adding PB_ISOLATE_MODE_CMA_ALLOC provide the information. At the same time change isolation flags to enum pb_isolate_mode (PB_ISOLATE_MODE_MEM_OFFLINE, PB_ISOLATE_MODE_CMA_ALLOC, PB_ISOLATE_MODE_OTHER). Remove REPORT_FAILURE and check PB_ISOLATE_MODE_MEM_OFFLINE, since only PB_ISOLATE_MODE_MEM_OFFLINE reports isolation failures. alloc_contig_range() no longer needs migratetype. Replace it with a newly defined acr_flags_t to tell if an allocation is for CMA. So does __alloc_contig_migrate_range(). Add ACR_FLAGS_NONE (set to 0) to indicate ordinary allocations. Link: https://lkml.kernel.org/r/20250617021115.2331563-7-ziy@nvidia.com Signed-off-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Hildenbrand <david@redhat.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Richard Chang <richardycc@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-13mm/page_isolation: remove migratetype from undo_isolate_page_range()Zi Yan
Since migratetype is no longer overwritten during pageblock isolation, undoing pageblock isolation no longer needs which migratetype to restore. Link: https://lkml.kernel.org/r/20250617021115.2331563-6-ziy@nvidia.com Signed-off-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Richard Chang <richardycc@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-13mm/page_alloc: add support for initializing pageblock as isolatedZi Yan
MIGRATE_ISOLATE is a standalone bit, so a pageblock cannot be initialized to just MIGRATE_ISOLATE. Add init_pageblock_migratetype() to enable initialize a pageblock with a migratetype and isolated. Link: https://lkml.kernel.org/r/20250617021115.2331563-4-ziy@nvidia.com Signed-off-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Hildenbrand <david@redhat.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Richard Chang <richardycc@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-13mm/page_alloc: pageblock flags functions clean upZi Yan
Patch series "Make MIGRATE_ISOLATE a standalone bit", v10. This patchset moves MIGRATE_ISOLATE to a standalone bit to avoid being overwritten during pageblock isolation process. Currently, MIGRATE_ISOLATE is part of enum migratetype (in include/linux/mmzone.h), thus, setting a pageblock to MIGRATE_ISOLATE overwrites its original migratetype. This causes pageblock migratetype loss during alloc_contig_range() and memory offline, especially when the process fails due to a failed pageblock isolation and the code tries to undo the finished pageblock isolations. In terms of performance for changing pageblock types, no performance change is observed: 1. I used perf to collect stats of offlining and onlining all memory of a 40GB VM 10 times and see that get_pfnblock_flags_mask() and set_pfnblock_flags_mask() take about 0.12% and 0.02% of the whole process respectively with and without this patchset across 3 runs. 2. I used perf to collect stats of dd from /dev/random to a 40GB tmpfs file and find get_pfnblock_flags_mask() takes about 0.05% of the process with and without this patchset across 3 runs. This patch (of 6): No functional change is intended. 1. Add __NR_PAGEBLOCK_BITS for the number of pageblock flag bits and use roundup_pow_of_two(__NR_PAGEBLOCK_BITS) as NR_PAGEBLOCK_BITS to take right amount of bits for pageblock flags. 2. Rename PB_migrate_skip to PB_compact_skip. 3. Add {get,set,clear}_pfnblock_bit() to operate one a standalone bit, like PB_compact_skip. 3. Make {get,set}_pfnblock_flags_mask() internal functions and use {get,set}_pfnblock_migratetype() for pageblock migratetype operations. 4. Move pageblock flags common code to get_pfnblock_bitmap_bitidx(). 3. Use MIGRATETYPE_MASK to get the migratetype of a pageblock from its flags. 4. Use PB_migrate_end in the definition of MIGRATETYPE_MASK instead of PB_migrate_bits. 5. Add a comment on is_migrate_cma_folio() to prevent one from changing it to use get_pageblock_migratetype() and causing issues. Link: https://lkml.kernel.org/r/20250617021115.2331563-1-ziy@nvidia.com Link: https://lkml.kernel.org/r/20250617021115.2331563-2-ziy@nvidia.com Signed-off-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Hildenbrand <david@redhat.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Richard Chang <richardycc@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-13mm,memory_hotplug: drop status_change_nid parameter from memory_notifyOscar Salvador
There no users left of status_change_nid, so drop it from memory_notify struct. Link: https://lkml.kernel.org/r/20250616135158.450136-12-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Suggested-by: David Hildenbrand <david@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Harry Yoo <harry.yoo@oracle.com> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Joanthan Cameron <Jonathan.Cameron@huawei.com> Cc: Rakie Kim <rakie.kim@sk.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-13mm,memory_hotplug: implement numa node notifierOscar Salvador
There are at least six consumers of hotplug_memory_notifier that what they really are interested in is whether any numa node changed its state, e.g: going from having memory to not having memory and vice versa. Implement a specific notifier for numa nodes when their state gets changed, which will later be used by those consumers that are only interested in numa node state changes. Add documentation as well. [dan.carpenter@linaro.org: set failure reason in offline_pages()] Link: https://lkml.kernel.org/r/be4fd31b-7d09-46b0-8329-6d0464ffa7a5@sabinyo.mountain Link: https://lkml.kernel.org/r/20250616135158.450136-4-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Hildenbrand <david@redhat.com> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Rakie Kim <rakie.kim@sk.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-13mm,memory_hotplug: remove status_change_nid_normal and update documentationOscar Salvador
Now that the last user of status_change_nid_normal is gone, we can remove it. Update documentation accordingly. Link: https://lkml.kernel.org/r/20250616135158.450136-3-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Hildenbrand <david@redhat.com> Cc: Harry Yoo <harry.yoo@oracle.com> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Joanthan Cameron <Jonathan.Cameron@huawei.com> Cc: Rakie Kim <rakie.kim@sk.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09drivers/base/node: rename __register_one_node() to register_one_node()Donet Tom
The register_one_node() function was a simple wrapper around __register_one_node(). To simplify the code, register_one_node() has been removed, and __register_one_node() has been renamed to register_one_node(). Link: https://lkml.kernel.org/r/8262cd0f44eeb048a1fcd3ac8382760d7f7dea60.1748452242.git.donettom@linux.ibm.com Signed-off-by: Donet Tom <donettom@linux.ibm.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09drivers/base/node: rename register_memory_blocks_under_node() and remove ↵Donet Tom
context argument The function register_memory_blocks_under_node() is now only called from the memory hotplug path, as register_memory_blocks_under_node_early() handles registration during early boot. Therefore, the context argument used to differentiate between early boot and hotplug is no longer needed and was removed. Since the function is only called from the hotplug path, we renamed register_memory_blocks_under_node() to register_memory_blocks_under_node_hotplug() Link: https://lkml.kernel.org/r/907c22292b0ee4975107876efc875c75c11badd9.1748452242.git.donettom@linux.ibm.com Signed-off-by: Donet Tom <donettom@linux.ibm.com> Acked-by: Oscar Salvador <osalvador@suse.de> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12mm: use for_each_valid_pfn() in memory_hotplugDavid Woodhouse
Link: https://lkml.kernel.org/r/20250423133821.789413-7-dwmw2@infradead.org Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Ruihan Li <lrh2000@pku.edu.cn> Cc: Will Deacon <will@kernel.org> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-04-01mm/memory_hotplug: fix call folio_test_large with tail page in do_migrate_rangeJinjiang Tu
We triggered the below BUG: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x2 pfn:0x240402 head: order:9 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x1ffffe0000000040(head|node=1|zone=3|lastcpupid=0x1ffff) page_type: f4(hugetlb) page dumped because: VM_BUG_ON_PAGE(page->compound_head & 1) ------------[ cut here ]------------ kernel BUG at ./include/linux/page-flags.h:310! Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP Modules linked in: CPU: 7 UID: 0 PID: 166 Comm: sh Not tainted 6.14.0-rc7-dirty #374 Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : const_folio_flags+0x3c/0x58 lr : const_folio_flags+0x3c/0x58 Call trace: const_folio_flags+0x3c/0x58 (P) do_migrate_range+0x164/0x720 offline_pages+0x63c/0x6fc memory_subsys_offline+0x190/0x1f4 device_offline+0xc0/0x13c state_store+0x90/0xd8 dev_attr_store+0x18/0x2c sysfs_kf_write+0x44/0x54 kernfs_fop_write_iter+0x120/0x1cc vfs_write+0x240/0x378 ksys_write+0x70/0x108 __arm64_sys_write+0x1c/0x28 invoke_syscall+0x48/0x10c el0_svc_common.constprop.0+0x40/0xe0 When allocating a hugetlb folio, between the folio is taken from buddy and prep_compound_page() is called, start_isolate_page_range() and do_migrate_range() is called. When do_migrate_range() scans the head page of the hugetlb folio, the compound_head field isn't set, so scans the tail page next. And at this time, the compound_head field of tail page is set, folio_test_large() is called by tail page, thus triggers VM_BUG_ON(). To fix it, get folio refcount before calling folio_test_large(). Link: https://lkml.kernel.org/r/20250324131750.1551884-1-tujinjiang@huawei.com Fixes: 8135d8926c08 ("mm: memory_hotplug: memory hotremove supports thp migration") Fixes: b62b51d2d159 ("mm: memory_hotplug: remove head variable in do_migrate_range()") Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com> Acked-by: Oscar Salvador <osalvador@suse.de> Acked-by: David Hildenbrand <david@redhat.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-21mm/hwpoison: introduce folio_contain_hwpoisoned_page() helperJinjiang Tu
Patch series "mm/vmscan: don't try to reclaim hwpoison folio". Fix a bug during memory reclaim if folio is hwpoisoned. This patch (of 2): Introduce helper folio_contain_hwpoisoned_page() to check if the entire folio is hwpoisoned or it contains hwpoisoned pages. Link: https://lkml.kernel.org/r/20250318083939.987651-1-tujinjiang@huawei.com Link: https://lkml.kernel.org/r/20250318083939.987651-2-tujinjiang@huawei.com Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com> Acked-by: Miaohe Lin <linmiaohe@huawei.com> Cc: David Hildenbrand <david@redhat.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: <stable@vger,kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-05hwpoison, memory_hotplug: lock folio before unmap hwpoisoned folioMa Wupeng
Commit b15c87263a69 ("hwpoison, memory_hotplug: allow hwpoisoned pages to be offlined) add page poison checks in do_migrate_range in order to make offline hwpoisoned page possible by introducing isolate_lru_page and try_to_unmap for hwpoisoned page. However folio lock must be held before calling try_to_unmap. Add it to fix this problem. Warning will be produced if folio is not locked during unmap: ------------[ cut here ]------------ kernel BUG at ./include/linux/swapops.h:400! Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP Modules linked in: CPU: 4 UID: 0 PID: 411 Comm: bash Tainted: G W 6.13.0-rc1-00016-g3c434c7ee82a-dirty #41 Tainted: [W]=WARN Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : try_to_unmap_one+0xb08/0xd3c lr : try_to_unmap_one+0x3dc/0xd3c Call trace: try_to_unmap_one+0xb08/0xd3c (P) try_to_unmap_one+0x3dc/0xd3c (L) rmap_walk_anon+0xdc/0x1f8 rmap_walk+0x3c/0x58 try_to_unmap+0x88/0x90 unmap_poisoned_folio+0x30/0xa8 do_migrate_range+0x4a0/0x568 offline_pages+0x5a4/0x670 memory_block_action+0x17c/0x374 memory_subsys_offline+0x3c/0x78 device_offline+0xa4/0xd0 state_store+0x8c/0xf0 dev_attr_store+0x18/0x2c sysfs_kf_write+0x44/0x54 kernfs_fop_write_iter+0x118/0x1a8 vfs_write+0x3a8/0x4bc ksys_write+0x6c/0xf8 __arm64_sys_write+0x1c/0x28 invoke_syscall+0x44/0x100 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x30/0xd0 el0t_64_sync_handler+0xc8/0xcc el0t_64_sync+0x198/0x19c Code: f9407be0 b5fff320 d4210000 17ffff97 (d4210000) ---[ end trace 0000000000000000 ]--- Link: https://lkml.kernel.org/r/20250217014329.3610326-4-mawupeng1@huawei.com Fixes: b15c87263a69 ("hwpoison, memory_hotplug: allow hwpoisoned pages to be offlined") Signed-off-by: Ma Wupeng <mawupeng1@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-05mm: memory-hotplug: check folio ref count first in do_migrate_rangeMa Wupeng
If a folio has an increased reference count, folio_try_get() will acquire it, perform necessary operations, and then release it. In the case of a poisoned folio without an elevated reference count (which is unlikely for memory-failure), folio_try_get() will simply bypass it. Therefore, relocate the folio_try_get() function, responsible for checking and acquiring this reference count at first. Link: https://lkml.kernel.org/r/20250217014329.3610326-3-mawupeng1@huawei.com Signed-off-by: Ma Wupeng <mawupeng1@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-05mm: memory-failure: update ttu flag inside unmap_poisoned_folioMa Wupeng
Patch series "mm: memory_failure: unmap poisoned folio during migrate properly", v3. Fix two bugs during folio migration if the folio is poisoned. This patch (of 3): Commit 6da6b1d4a7df ("mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON") introduce TTU_HWPOISON to replace TTU_IGNORE_HWPOISON in order to stop send SIGBUS signal when accessing an error page after a memory error on a clean folio. However during page migration, anon folio must be set with TTU_HWPOISON during unmap_*(). For pagecache we need some policy just like the one in hwpoison_user_mappings to set this flag. So move this policy from hwpoison_user_mappings to unmap_poisoned_folio to handle this warning properly. Warning will be produced during unamp poison folio with the following log: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 365 at mm/rmap.c:1847 try_to_unmap_one+0x8fc/0xd3c Modules linked in: CPU: 1 UID: 0 PID: 365 Comm: bash Tainted: G W 6.13.0-rc1-00018-gacdb4bbda7ab #42 Tainted: [W]=WARN Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : try_to_unmap_one+0x8fc/0xd3c lr : try_to_unmap_one+0x3dc/0xd3c Call trace: try_to_unmap_one+0x8fc/0xd3c (P) try_to_unmap_one+0x3dc/0xd3c (L) rmap_walk_anon+0xdc/0x1f8 rmap_walk+0x3c/0x58 try_to_unmap+0x88/0x90 unmap_poisoned_folio+0x30/0xa8 do_migrate_range+0x4a0/0x568 offline_pages+0x5a4/0x670 memory_block_action+0x17c/0x374 memory_subsys_offline+0x3c/0x78 device_offline+0xa4/0xd0 state_store+0x8c/0xf0 dev_attr_store+0x18/0x2c sysfs_kf_write+0x44/0x54 kernfs_fop_write_iter+0x118/0x1a8 vfs_write+0x3a8/0x4bc ksys_write+0x6c/0xf8 __arm64_sys_write+0x1c/0x28 invoke_syscall+0x44/0x100 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x30/0xd0 el0t_64_sync_handler+0xc8/0xcc el0t_64_sync+0x198/0x19c ---[ end trace 0000000000000000 ]--- [mawupeng1@huawei.com: unmap_poisoned_folio(): remove shadowed local `mapping', per Miaohe] Link: https://lkml.kernel.org/r/20250219060653.3849083-1-mawupeng1@huawei.com Link: https://lkml.kernel.org/r/20250217014329.3610326-1-mawupeng1@huawei.com Link: https://lkml.kernel.org/r/20250217014329.3610326-2-mawupeng1@huawei.com Fixes: 6da6b1d4a7df ("mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON") Signed-off-by: Ma Wupeng <mawupeng1@huawei.com> Suggested-by: David Hildenbrand <david@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Ma Wupeng <mawupeng1@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-25mm: add build-time option for hotplug memory default online typeGregory Price
Memory hotplug presently auto-onlines memory into a zone the kernel deems appropriate if CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE=y. The memhp_default_state boot param enables runtime config, but it's not possible to do this at build-time. Remove CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE, and replace it with CONFIG_MHP_DEFAULT_ONLINE_TYPE_* choices that sync with the boot param. Selections: CONFIG_MHP_DEFAULT_ONLINE_TYPE_OFFLINE => mhp_default_online_type = "offline" Memory will not be onlined automatically. CONFIG_MHP_DEFAULT_ONLINE_TYPE_ONLINE_AUTO => mhp_default_online_type = "online" Memory will be onlined automatically in a zone deemed. appropriate by the kernel. CONFIG_MHP_DEFAULT_ONLINE_TYPE_ONLINE_KERNEL => mhp_default_online_type = "online_kernel" Memory will be onlined automatically. The zone may allow kernel data (e.g. ZONE_NORMAL). CONFIG_MHP_DEFAULT_ONLINE_TYPE_ONLINE_MOVABLE => mhp_default_online_type = "online_movable" Memory will be onlined automatically. The zone will be ZONE_MOVABLE. Default to CONFIG_MHP_DEFAULT_ONLINE_TYPE_OFFLINE to match the existing default CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE=n behavior. Existing users of CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE=y should use CONFIG_MHP_DEFAULT_ONLINE_TYPE_ONLINE_AUTO. [gourry@gourry.net: update KConfig comments] Link: https://lkml.kernel.org/r/20241226182918.648799-1-gourry@gourry.net Link: https://lkml.kernel.org/r/20241220210709.300066-1-gourry@gourry.net Signed-off-by: Gregory Price <gourry@gourry.net> Acked-by: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-13mm/memory_hotplug: don't use __GFP_HARDWALL when migrating pages via memory ↵David Hildenbrand
offlining We'll migrate pages allocated by other context; respecting the cpuset of the memory offlining context when allocating a migration target does not make sense. Drop the __GFP_HARDWALL by using GFP_KERNEL. Note that in an ideal world, migration code could figure out the cpuset of the original context and take that into consideration. Link: https://lkml.kernel.org/r/20241205090508.2095225-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Suggested-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Oscar Salvador <osalvador@suse.de> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-13mm/page_isolation: don't pass gfp flags to start_isolate_page_range()David Hildenbrand
The parameter is unused, so let's stop passing it. Link: https://lkml.kernel.org/r/20241203094732.200195-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Naveen N Rao <naveen@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-13mm/memory_hotplug: move debug_pagealloc_map_pages() into online_pages_range()David Hildenbrand
In the near future, we want to have a single way to handover PageOffline pages to the buddy, whereby they could have: (a) Never been exposed to the buddy before: kept PageOffline when onlining the memory block. (b) Been allocated from the buddy, for example using alloc_contig_range() to then be set PageOffline, Let's start by making generic_online_page()->__free_pages_core() less special compared to ordinary page freeing (e.g., free_contig_range()), and perform the debug_pagealloc_map_pages() call unconditionally, even when the online callback might decide to keep the pages offline. All pages are already initialized with PageOffline, so nobody touches them either way. Link: https://lkml.kernel.org/r/20241203102050.223318-1-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06kaslr: rename physmem_end and PHYSMEM_END to direct_map_physmem_endJohn Hubbard
For clarity. It's increasingly hard to reason about the code, when KASLR is moving around the boundaries. In this case where KASLR is randomizing the location of the kernel image within physical memory, the maximum number of address bits for physical memory has not changed. What has changed is the ending address of memory that is allowed to be directly mapped by the kernel. Let's name the variable, and the associated macro accordingly. Also, enhance the comment above the direct_map_physmem_end definition, to further clarify how this all works. Link: https://lkml.kernel.org/r/20241009025024.89813-1-jhubbard@nvidia.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Will Deacon <will@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alistair Popple <apopple@nvidia.com> Cc: Jordan Niethe <jniethe@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-21Merge tag 'mm-stable-2024-09-20-02-31' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Along with the usual shower of singleton patches, notable patch series in this pull request are: - "Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds consistency to the APIs and behaviour of these two core allocation functions. This also simplifies/enables Rustification. - "Some cleanups for shmem" from Baolin Wang. No functional changes - mode code reuse, better function naming, logic simplifications. - "mm: some small page fault cleanups" from Josef Bacik. No functional changes - code cleanups only. - "Various memory tiering fixes" from Zi Yan. A small fix and a little cleanup. - "mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and simplifications and .text shrinkage. - "Kernel stack usage histogram" from Pasha Tatashin and Shakeel Butt. This is a feature, it adds new feilds to /proc/vmstat such as $ grep kstack /proc/vmstat kstack_1k 3 kstack_2k 188 kstack_4k 11391 kstack_8k 243 kstack_16k 0 which tells us that 11391 processes used 4k of stack while none at all used 16k. Useful for some system tuning things, but partivularly useful for "the dynamic kernel stack project". - "kmemleak: support for percpu memory leak detect" from Pavel Tikhomirov. Teaches kmemleak to detect leaksage of percpu memory. - "mm: memcg: page counters optimizations" from Roman Gushchin. "3 independent small optimizations of page counters". - "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from David Hildenbrand. Improves PTE/PMD splitlock detection, makes powerpc/8xx work correctly by design rather than by accident. - "mm: remove arch_make_page_accessible()" from David Hildenbrand. Some folio conversions which make arch_make_page_accessible() unneeded. - "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David Finkel. Cleans up and fixes our handling of the resetting of the cgroup/process peak-memory-use detector. - "Make core VMA operations internal and testable" from Lorenzo Stoakes. Rationalizaion and encapsulation of the VMA manipulation APIs. With a view to better enable testing of the VMA functions, even from a userspace-only harness. - "mm: zswap: fixes for global shrinker" from Takero Funaki. Fix issues in the zswap global shrinker, resulting in improved performance. - "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill in some missing info in /proc/zoneinfo. - "mm: replace follow_page() by folio_walk" from David Hildenbrand. Code cleanups and rationalizations (conversion to folio_walk()) resulting in the removal of follow_page(). - "improving dynamic zswap shrinker protection scheme" from Nhat Pham. Some tuning to improve zswap's dynamic shrinker. Significant reductions in swapin and improvements in performance are shown. - "mm: Fix several issues with unaccepted memory" from Kirill Shutemov. Improvements to the new unaccepted memory feature, - "mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on DAX PUDs. This was missing, although nobody seems to have notied yet. - "Introduce a store type enum for the Maple tree" from Sidhartha Kumar. Cleanups and modest performance improvements for the maple tree library code. - "memcg: further decouple v1 code from v2" from Shakeel Butt. Move more cgroup v1 remnants away from the v2 memcg code. - "memcg: initiate deprecation of v1 features" from Shakeel Butt. Adds various warnings telling users that memcg v1 features are deprecated. - "mm: swap: mTHP swap allocator base on swap cluster order" from Chris Li. Greatly improves the success rate of the mTHP swap allocation. - "mm: introduce numa_memblks" from Mike Rapoport. Moves various disparate per-arch implementations of numa_memblk code into generic code. - "mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly improves the performance of munmap() of swap-filled ptes. - "support large folio swap-out and swap-in for shmem" from Baolin Wang. With this series we no longer split shmem large folios into simgle-page folios when swapping out shmem. - "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice performance improvements and code reductions for gigantic folios. - "support shmem mTHP collapse" from Baolin Wang. Adds support for khugepaged's collapsing of shmem mTHP folios. - "mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect() performance regression due to the addition of mseal(). - "Increase the number of bits available in page_type" from Matthew Wilcox. Increases the number of bits available in page_type! - "Simplify the page flags a little" from Matthew Wilcox. Many legacy page flags are now folio flags, so the page-based flags and their accessors/mutators can be removed. - "mm: store zero pages to be swapped out in a bitmap" from Usama Arif. An optimization which permits us to avoid writing/reading zero-filled zswap pages to backing store. - "Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race window which occurs when a MAP_FIXED operqtion is occurring during an unrelated vma tree walk. - "mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of the vma_merge() functionality, making ot cleaner, more testable and better tested. - "misc fixups for DAMON {self,kunit} tests" from SeongJae Park. Minor fixups of DAMON selftests and kunit tests. - "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang. Code cleanups and folio conversions. - "Shmem mTHP controls and stats improvements" from Ryan Roberts. Cleanups for shmem controls and stats. - "mm: count the number of anonymous THPs per size" from Barry Song. Expose additional anon THP stats to userspace for improved tuning. - "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more folio conversions and removal of now-unused page-based APIs. - "replace per-quota region priorities histogram buffer with per-context one" from SeongJae Park. DAMON histogram rationalization. - "Docs/damon: update GitHub repo URLs and maintainer-profile" from SeongJae Park. DAMON documentation updates. - "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and improve related doc and warn" from Jason Wang: fixes usage of page allocator __GFP_NOFAIL and GFP_ATOMIC flags. - "mm: split underused THPs" from Yu Zhao. Improve THP=always policy. This was overprovisioning THPs in sparsely accessed memory areas. - "zram: introduce custom comp backends API" frm Sergey Senozhatsky. Add support for zram run-time compression algorithm tuning. - "mm: Care about shadow stack guard gap when getting an unmapped area" from Mark Brown. Fix up the various arch_get_unmapped_area() implementations to better respect guard areas. - "Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability of mem_cgroup_iter() and various code cleanups. - "mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge pfnmap support. - "resource: Fix region_intersects() vs add_memory_driver_managed()" from Huang Ying. Fix a bug in region_intersects() for systems with CXL memory. - "mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches a couple more code paths to correctly recover from the encountering of poisoned memry. - "mm: enable large folios swap-in support" from Barry Song. Support the swapin of mTHP memory into appropriately-sized folios, rather than into single-page folios" * tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (416 commits) zram: free secondary algorithms names uprobes: turn xol_area->pages[2] into xol_area->page uprobes: introduce the global struct vm_special_mapping xol_mapping Revert "uprobes: use vm_special_mapping close() functionality" mm: support large folios swap-in for sync io devices mm: add nr argument in mem_cgroup_swapin_uncharge_swap() helper to support large folios mm: fix swap_read_folio_zeromap() for large folios with partial zeromap mm/debug_vm_pgtable: Use pxdp_get() for accessing page table entries set_memory: add __must_check to generic stubs mm/vma: return the exact errno in vms_gather_munmap_vmas() memcg: cleanup with !CONFIG_MEMCG_V1 mm/show_mem.c: report alloc tags in human readable units mm: support poison recovery from copy_present_page() mm: support poison recovery from do_cow_fault() resource, kunit: add test case for region_intersects() resource: make alloc_free_mem_region() works for iomem_resource mm: z3fold: deprecate CONFIG_Z3FOLD vfio/pci: implement huge_fault support mm/arm64: support large pfn mappings mm/x86: support large pfn mappings ...
2024-09-03mm: memory_hotplug: unify Huge/LRU/non-LRU movable folio isolationKefeng Wang
Use the isolate_folio_to_list() to unify hugetlb/LRU/non-LRU folio isolation, which cleanup code a bit and save a few calls to compound_head(). [wangkefeng.wang@huawei.com: various fixes] Link: https://lkml.kernel.org/r/20240829150500.2599549-1-wangkefeng.wang@huawei.com Link: https://lkml.kernel.org/r/20240827114728.3212578-6-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Dan Carpenter <dan.carpenter@linaro.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-03mm: memory_hotplug: check hwpoisoned page firstly in do_migrate_range()Kefeng Wang
Commit b15c87263a69 ("hwpoison, memory_hotplug: allow hwpoisoned pages to be offlined") don't handle the hugetlb pages, the endless loop still occur if offline a hwpoison hugetlb page, luckly, after the commit e591ef7d96d6 ("mm, hwpoison,hugetlb,memory_hotplug: hotremove memory section with hwpoisoned hugepage"), the HPageMigratable of hugetlb page will be cleared, and the hwpoison hugetlb page will be skipped in scan_movable_pages(), so the endless loop issue is fixed. However if the HPageMigratable() check passed(without reference and lock), the hugetlb page may be hwpoisoned, it won't cause issue since the hwpoisoned page will be handled correctly in the next movable pages scan loop, and it will be isolated in do_migrate_range() but fails to migrate. In order to avoid the unnecessary isolation and unify all hwpoisoned page handling, let's unconditionally check hwpoison firstly, and if it is a hwpoisoned hugetlb page, try to unmap it as the catch all safety net like normal page does. Link: https://lkml.kernel.org/r/20240827114728.3212578-4-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Dan Carpenter <dan.carpenter@linaro.org> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-03mm: memory_hotplug: remove head variable in do_migrate_range()Kefeng Wang
Patch series "mm: memory_hotplug: improve do_migrate_range()", v3. Unify hwpoisoned page handling and isolation of HugeTLB/LRU/non-LRU movable page, also convert to use folios in do_migrate_range(). This patch (of 5): Directly use a folio for HugeTLB and THP when calculate the next pfn, then remove unused head variable. Link: https://lkml.kernel.org/r/20240827114728.3212578-1-wangkefeng.wang@huawei.com Link: https://lkml.kernel.org/r/20240827114728.3212578-2-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Dan Carpenter <dan.carpenter@linaro.org> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01mm/memory_hotplug: get rid of __refWei Yang
After commit 73db3abdca58 ("init/modpost: conditionally check section mismatch to __meminit*"), we can get rid of __ref annotations. Link: https://lkml.kernel.org/r/20240726010157.6177-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-08-20x86/kaslr: Expose and use the end of the physical memory address spaceThomas Gleixner
iounmap() on x86 occasionally fails to unmap because the provided valid ioremap address is not below high_memory. It turned out that this happens due to KASLR. KASLR uses the full address space between PAGE_OFFSET and vaddr_end to randomize the starting points of the direct map, vmalloc and vmemmap regions. It thereby limits the size of the direct map by using the installed memory size plus an extra configurable margin for hot-plug memory. This limitation is done to gain more randomization space because otherwise only the holes between the direct map, vmalloc, vmemmap and vaddr_end would be usable for randomizing. The limited direct map size is not exposed to the rest of the kernel, so the memory hot-plug and resource management related code paths still operate under the assumption that the available address space can be determined with MAX_PHYSMEM_BITS. request_free_mem_region() allocates from (1 << MAX_PHYSMEM_BITS) - 1 downwards. That means the first allocation happens past the end of the direct map and if unlucky this address is in the vmalloc space, which causes high_memory to become greater than VMALLOC_START and consequently causes iounmap() to fail for valid ioremap addresses. MAX_PHYSMEM_BITS cannot be changed for that because the randomization does not align with address bit boundaries and there are other places which actually require to know the maximum number of address bits. All remaining usage sites of MAX_PHYSMEM_BITS have been analyzed and found to be correct. Cure this by exposing the end of the direct map via PHYSMEM_END and use that for the memory hot-plug and resource management related places instead of relying on MAX_PHYSMEM_BITS. In the KASLR case PHYSMEM_END maps to a variable which is initialized by the KASLR initialization and otherwise it is based on MAX_PHYSMEM_BITS as before. To prevent future hickups add a check into add_pages() to catch callers trying to add memory above PHYSMEM_END. Fixes: 0483e1fa6e09 ("x86/mm: Implement ASLR for kernel memory regions") Reported-by: Max Ramanouski <max8rr8@gmail.com> Reported-by: Alistair Popple <apopple@nvidia.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-By: Max Ramanouski <max8rr8@gmail.com> Tested-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: Kees Cook <kees@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/87ed6soy3z.ffs@tglx
2024-07-12mm/page_alloc: put __free_pages_core() in __meminit sectionWei Yang
__free_pages_core() is only used in bootmem init and hot-add memory init path. Let's put it in __meminit section. Link: https://lkml.kernel.org/r/20240706061615.30322-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03mm/memory_hotplug: skip adjust_managed_page_count() for PageOffline() pages ↵David Hildenbrand
when offlining We currently have a hack for virtio-mem in place to handle memory offlining with PageOffline pages for which we already adjusted the managed page count. Let's enlighten memory offlining code so we can get rid of that hack, and document the situation. Link: https://lkml.kernel.org/r/20240607090939.89524-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Oscar Salvador <osalvador@suse.de> Cc: Alexander Potapenko <glider@google.com> Cc: Dexuan Cui <decui@microsoft.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eugenio Pérez <eperezma@redhat.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Marco Elver <elver@google.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Wei Liu <wei.liu@kernel.org> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03mm/memory_hotplug: initialize memmap of !ZONE_DEVICE with PageOffline() ↵David Hildenbrand
instead of PageReserved() We currently initialize the memmap such that PG_reserved is set and the refcount of the page is 1. In virtio-mem code, we have to manually clear that PG_reserved flag to make memory offlining with partially hotplugged memory blocks possible: has_unmovable_pages() would otherwise bail out on such pages. We want to avoid PG_reserved where possible and move to typed pages instead. Further, we want to further enlighten memory offlining code about PG_offline: offline pages in an online memory section. One example is handling managed page count adjustments in a cleaner way during memory offlining. So let's initialize the pages with PG_offline instead of PG_reserved. generic_online_page()->__free_pages_core() will now clear that flag before handing that memory to the buddy. Note that the page refcount is still 1 and would forbid offlining of such memory except when special care is take during GOING_OFFLINE as currently only implemented by virtio-mem. With this change, we can now get non-PageReserved() pages in the XEN balloon list. From what I can tell, that can already happen via decrease_reservation(), so that should be fine. HV-balloon should not really observe a change: partial online memory blocks still cannot get surprise-offlined, because the refcount of these PageOffline() pages is 1. Update virtio-mem, HV-balloon and XEN-balloon code to be aware that hotplugged pages are now PageOffline() instead of PageReserved() before they are handed over to the buddy. We'll leave the ZONE_DEVICE case alone for now. Note that self-hosted vmemmap pages will no longer be marked as reserved. This matches ordinary vmemmap pages allocated from the buddy during memory hotplug. Now, really only vmemmap pages allocated from memblock during early boot will be marked reserved. Existing PageReserved() checks seem to be handling all relevant cases correctly even after this change. Link: https://lkml.kernel.org/r/20240607090939.89524-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Oscar Salvador <osalvador@suse.de> [generic memory-hotplug bits] Cc: Alexander Potapenko <glider@google.com> Cc: Dexuan Cui <decui@microsoft.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eugenio Pérez <eperezma@redhat.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Marco Elver <elver@google.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Wei Liu <wei.liu@kernel.org> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03mm: pass meminit_context to __free_pages_core()David Hildenbrand
Patch series "mm/memory_hotplug: use PageOffline() instead of PageReserved() for !ZONE_DEVICE". This can be a considered a long-overdue follow-up to some parts of [1]. The patches are based on [2], but they are not strictly required -- just makes it clearer why we can use adjust_managed_page_count() for memory hotplug without going into details about highmem. We stop initializing pages with PageReserved() in memory hotplug code -- except when dealing with ZONE_DEVICE for now. Instead, we use PageOffline(): all pages are initialized to PageOffline() when onlining a memory section, and only the ones actually getting exposed to the system/page allocator will get PageOffline cleared. This way, we enlighten memory hotplug more about PageOffline() pages and can cleanup some hacks we have in virtio-mem code. What about ZONE_DEVICE? PageOffline() is wrong, but we might just stop using PageReserved() for them later by simply checking for is_zone_device_page() at suitable places. That will be a separate patch set / proposal. This primarily affects virtio-mem, HV-balloon and XEN balloon. I only briefly tested with virtio-mem, which benefits most from these cleanups. [1] https://lore.kernel.org/all/20191024120938.11237-1-david@redhat.com/ [2] https://lkml.kernel.org/r/20240607083711.62833-1-david@redhat.com This patch (of 3): In preparation for further changes, let's teach __free_pages_core() about the differences of memory hotplug handling. Move the memory hotplug specific handling from generic_online_page() to __free_pages_core(), use adjust_managed_page_count() on the memory hotplug path, and spell out why memory freed via memblock cannot currently use adjust_managed_page_count(). [david@redhat.com: add missed CONFIG_DEFERRED_STRUCT_PAGE_INIT] Link: https://lkml.kernel.org/r/b72e6efd-fb0a-459c-b1a0-88a98e5b19e2@redhat.com [david@redhat.com: fix up the memblock comment, per Oscar] Link: https://lkml.kernel.org/r/2ed64218-7f3b-4302-a5dc-27f060654fe2@redhat.com [david@redhat.com: add the parameter name also in the declaration] Link: https://lkml.kernel.org/r/ca575956-f0dd-4fb9-a307-6b7621681ed9@redhat.com Link: https://lkml.kernel.org/r/20240607090939.89524-1-david@redhat.com Link: https://lkml.kernel.org/r/20240607090939.89524-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dexuan Cui <decui@microsoft.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eugenio Pérez <eperezma@redhat.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Marco Elver <elver@google.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Wei Liu <wei.liu@kernel.org> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03mm/memory_hotplug: prevent accessing by index=-1Anastasia Belova
nid may be equal to NUMA_NO_NODE=-1. Prevent accessing node_data array by invalid index with check for nid. Found by Linux Verification Center (linuxtesting.org) with SVACE. Link: https://lkml.kernel.org/r/20240606080659.18525-1-abelova@astralinux.ru Fixes: e83a437faa62 ("mm/memory_hotplug: introduce "auto-movable" online policy") Signed-off-by: Anastasia Belova <abelova@astralinux.ru> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03mm/memory_hotplug: drop memblock_phys_free() call in try_remove_memory()Jonathan Cameron
The call for memblock_phys_free() in try_remove_memory() does not balance any call to memblock_alloc() (or memblock_reserve() for that matter). There are no memblock_reserve() calls in mm/memory_hotplug.c, no memblock allocations possible after mm_core_init(), and even if memblock_add_node() called from add_memory_resource() would need to allocate memory, that memory would ba allocated from slab. The patch f9126ab9241f ("memory-hotplug: fix wrong edge when hot add a new node") that introduced that call to memblock_free() does not provide adequate description why that was required and tinkering with memblock in the context of memory hotplug on x86 seems bogus because x86 never kept memblock after boot anyway. Drop memblock_phys_free() call in try_remove_memory(). [rppt@kernel.org: rewrite the commit message] Link: https://lkml.kernel.org/r/20240605082049.973242-1-rppt@kernel.org Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-03mm/hugetlb: mm/memory_hotplug: use a folio in scan_movable_pages()Sidhartha Kumar
By using a folio in scan_movable_pages() we convert the last user of the page-based hugetlb information macro functions to the folio version. After this conversion, we can safely remove the page-based definitions from include/linux/hugetlb.h. Link: https://lkml.kernel.org/r/20240530171427.242018-1-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-05mm/hugetlb: rename dissolve_free_huge_pages() to dissolve_free_hugetlb_folios()Sidhartha Kumar
dissolve_free_huge_pages() only uses folios internally, rename it to dissolve_free_hugetlb_folios() and change the comments which reference it. [akpm@linux-foundation.org: remove unneeded `extern'] Link: https://lkml.kernel.org/r/20240412182139.120871-2-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25mm: record the migration reason for struct migration_target_controlBaolin Wang
Patch series "make the hugetlb migration strategy consistent", v2. As discussed in previous thread [1], there is an inconsistency when handling hugetlb migration. When handling the migration of freed hugetlb, it prevents fallback to other NUMA nodes in alloc_and_dissolve_hugetlb_folio(). However, when dealing with in-use hugetlb, it allows fallback to other NUMA nodes in alloc_hugetlb_folio_nodemask(), which can break the per-node hugetlb pool and might result in unexpected failures when node bound workloads doesn't get what is asssumed available. This patchset tries to make the hugetlb migration strategy more clear and consistent. Please find details in each patch. [1] https://lore.kernel.org/all/6f26ce22d2fcd523418a085f2c588fe0776d46e7.1706794035.git.baolin.wang@linux.alibaba.com/ This patch (of 2): To support different hugetlb allocation strategies during hugetlb migration based on various migration reasons, record the migration reason in the migration_target_control structure as a preparation. Link: https://lkml.kernel.org/r/cover.1709719720.git.baolin.wang@linux.alibaba.com Link: https://lkml.kernel.org/r/7b95d4981e07211f57139fc5b1f7ce91b920cee4.1709719720.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22mm/memory_hotplug: export mhp_supports_memmap_on_memory()Vishal Verma
In preparation for adding sysfs ABI to toggle memmap_on_memory semantics for drivers adding memory, export the mhp_supports_memmap_on_memory() helper. This allows drivers to check if memmap_on_memory support is available before trying to request it, and display an appropriate message if it isn't available. As part of this, remove the size argument to this - with recent updates to allow memmap_on_memory for larger ranges, and the internal splitting of altmaps into respective memory blocks, the size argument is meaningless. [akpm@linux-foundation.org: fix build] Link: https://lkml.kernel.org/r/20240124-vv-dax_abi-v7-4-20d16cb8d23d@intel.com Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Acked-by: David Hildenbrand <david@redhat.com> Suggested-by: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Li Zhijian <lizhijian@fujitsu.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-21mm/memory_hotplug: introduce MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE notifiersSumanth Korikkar
Patch series "implement "memmap on memory" feature on s390". This series provides "memmap on memory" support on s390 platform. "memmap on memory" allows struct pages array to be allocated from the hotplugged memory range instead of allocating it from main system memory. s390 currently preallocates struct pages array for all potentially possible memory, which ensures memory onlining always succeeds, but with the cost of significant memory consumption from the available system memory during boottime. In certain extreme configuration, this could lead to ipl failure. "memmap on memory" ensures struct pages array are populated from self contained hotplugged memory range instead of depleting the available system memory and this could eliminate ipl failure on s390 platform. On other platforms, system might go OOM when the physically hotplugged memory depletes the available memory before it is onlined. Hence, "memmap on memory" feature was introduced as described in commit a08a2ae34613 ("mm,memory_hotplug: allocate memmap from the added memory range"). Unlike other architectures, s390 memory blocks are not physically accessible until it is online. To make it physically accessible two new memory notifiers MEM_PREPARE_ONLINE / MEM_FINISH_OFFLINE are added and this notifier lets the hypervisor inform that the memory should be made physically accessible. This allows for "memmap on memory" initialization during memory hotplug onlining phase, which is performed before calling MEM_GOING_ONLINE notifier. Patch 1 introduces MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE memory notifiers to prepare the transition of memory to and from a physically accessible state. New mhp_flag MHP_OFFLINE_INACCESSIBLE is introduced to ensure altmap cannot be written when adding memory - before it is set online. This enhancement is crucial for implementing the "memmap on memory" feature for s390 in a subsequent patch. Patches 2 allocates vmemmap pages from self-contained memory range for s390. It allocates memory map (struct pages array) from the hotplugged memory range, rather than using system memory by passing altmap to vmemmap functions. Patch 3 removes unhandled memory notifier types on s390. Patch 4 implements MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE memory notifiers on s390. MEM_PREPARE_ONLINE memory notifier makes memory block physical accessible via sclp assign command. The notifier ensures self-contained memory maps are accessible and hence enabling the "memmap on memory" on s390. MEM_FINISH_OFFLINE memory notifier shifts the memory block to an inaccessible state via sclp unassign command. Patch 5 finally enables MHP_MEMMAP_ON_MEMORY on s390. This patch (of 5): Introduce MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE memory notifiers to prepare the transition of memory to and from a physically accessible state. This enhancement is crucial for implementing the "memmap on memory" feature for s390 in a subsequent patch. Platforms such as x86 can support physical memory hotplug via ACPI. When there is physical memory hotplug, ACPI event leads to the memory addition with the following callchain: acpi_memory_device_add() -> acpi_memory_enable_device() -> __add_memory() After this, the hotplugged memory is physically accessible, and altmap support prepared, before the "memmap on memory" initialization in memory_block_online() is called. On s390, memory hotplug works in a different way. The available hotplug memory has to be defined upfront in the hypervisor, but it is made physically accessible only when the user sets it online via sysfs, currently in the MEM_GOING_ONLINE notifier. This is too late and "memmap on memory" initialization is performed before calling MEM_GOING_ONLINE notifier. During the memory hotplug addition phase, altmap support is prepared and during the memory onlining phase s390 requires memory to be physically accessible and then subsequently initiate the "memmap on memory" initialization process. The memory provider will handle new MEM_PREPARE_ONLINE / MEM_FINISH_OFFLINE notifications and make the memory accessible. The mhp_flag MHP_OFFLINE_INACCESSIBLE is introduced and is relevant when used along with MHP_MEMMAP_ON_MEMORY, because the altmap cannot be written (e.g., poisoned) when adding memory -- before it is set online. This allows for adding memory with an altmap that is not currently made available by a hypervisor. When onlining that memory, the hypervisor can be instructed to make that memory accessible via the new notifiers and the onlining phase will not require any memory allocations, which is helpful in low-memory situations. All architectures ignore unknown memory notifiers. Therefore, the introduction of these new notifiers does not result in any functional modifications across architectures. Link: https://lkml.kernel.org/r/20240108132747.3238763-1-sumanthk@linux.ibm.com Link: https://lkml.kernel.org/r/20240108132747.3238763-2-sumanthk@linux.ibm.com Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Suggested-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Suggested-by: David Hildenbrand <david@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-01-12mm/memory_hotplug: fix memmap_on_memory sysfs value retrievalSumanth Korikkar
set_memmap_mode() stores the kernel parameter memmap mode as an integer. However, the get_memmap_mode() function utilizes param_get_bool() to fetch the value as a boolean, leading to potential endianness issue. On Big-endian architectures, the memmap_on_memory is consistently displayed as 'N' regardless of its actual status. To address this endianness problem, the solution involves obtaining the mode as an integer. This adjustment ensures the proper display of the memmap_on_memory parameter, presenting it as one of the following options: Force, Y, or N. Link: https://lkml.kernel.org/r/20240110140127.241451-1-sumanthk@linux.ibm.com Fixes: 2d1f649c7c08 ("mm/memory_hotplug: support memmap_on_memory when memmap is not aligned to pageblocks") Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Suggested-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: <stable@vger.kernel.org> [6.6+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-01-08mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDERKirill A. Shutemov
commit 23baf831a32c ("mm, treewide: redefine MAX_ORDER sanely") has changed the definition of MAX_ORDER to be inclusive. This has caused issues with code that was not yet upstream and depended on the previous definition. To draw attention to the altered meaning of the define, rename MAX_ORDER to MAX_PAGE_ORDER. Link: https://lkml.kernel.org/r/20231228144704.14033-2-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10mm/memory_hotplug: split memmap_on_memory requests across memblocksVishal Verma
The MHP_MEMMAP_ON_MEMORY flag for hotplugged memory is restricted to 'memblock_size' chunks of memory being added. Adding a larger span of memory precludes memmap_on_memory semantics. For users of hotplug such as kmem, large amounts of memory might get added from the CXL subsystem. In some cases, this amount may exceed the available 'main memory' to store the memmap for the memory being added. In this case, it is useful to have a way to place the memmap on the memory being added, even if it means splitting the addition into memblock-sized chunks. Change add_memory_resource() to loop over memblock-sized chunks of memory if caller requested memmap_on_memory, and if other conditions for it are met. Teach try_remove_memory() to also expect that a memory range being removed might have been split up into memblock sized chunks, and to loop through those as needed. This does preclude being able to use PUD mappings in the direct map; a proposal to how this could be optimized in the future is laid out here[1]. [1]: https://lore.kernel.org/linux-mm/b6753402-2de9-25b2-36e9-eacd49752b19@redhat.com/ Link: https://lkml.kernel.org/r/20231107-vv-kmem_memmap-v10-2-1253ec050ed0@intel.com Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Suggested-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Fan Ni <fan.ni@samsung.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>