1079 Commits
Author SHA1 Message Date
Linus Torvalds 40735a683b Merge tag 'mm-stable-2026-04-18-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more MM updates from Andrew Morton:

 - "Eliminate Dying Memory Cgroup" (Qi Zheng and Muchun Song)

   Address the longstanding "dying memcg problem". A situation wherein a
   no-longer-used memory control group will hang around for an extended
   period pointlessly consuming memory

 - "fix unexpected type conversions and potential overflows" (Qi Zheng)

   Fix a couple of potential 32-bit/64-bit issues which were identified
   during review of the "Eliminate Dying Memory Cgroup" series

 - "kho: history: track previous kernel version and kexec boot count"
   (Breno Leitao)

   Use Kexec Handover (KHO) to pass the previous kernel's version string
   and the number of kexec reboots since the last cold boot to the next
   kernel, and print it at boot time

 - "liveupdate: prevent double preservation" (Pasha Tatashin)

   Teach LUO to avoid managing the same file across different active
   sessions

 - "liveupdate: Fix module unloading and unregister API" (Pasha
   Tatashin)

   Address an issue with how LUO handles module reference counting and
   unregistration during module unloading

 - "zswap pool per-CPU acomp_ctx simplifications" (Kanchana Sridhar)

   Simplify and clean up the zswap crypto compression handling and
   improve the lifecycle management of zswap pool's per-CPU acomp_ctx
   resources

 - "mm/damon/core: fix damon_call()/damos_walk() vs kdmond exit race"
   (SeongJae Park)

   Address unlikely but possible leaks and deadlocks in damon_call() and
   damon_walk()

 - "mm/damon/core: validate damos_quota_goal->nid" (SeongJae Park)

   Fix a couple of root-only wild pointer dereferences

 - "Docs/admin-guide/mm/damon: warn commit_inputs vs other params race"
   (SeongJae Park)

   Update the DAMON documentation to warn operators about potential
   races which can occur if the commit_inputs parameter is altered at
   the wrong time

 - "Minor hmm_test fixes and cleanups" (Alistair Popple)

   Bugfixes and a cleanup for the HMM kernel selftests

 - "Modify memfd_luo code" (Chenghao Duan)

   Cleanups, simplifications and speedups to the memfd_lou code

 - "mm, kvm: allow uffd support in guest_memfd" (Mike Rapoport)

   Support for userfaultfd in guest_memfd

 - "selftests/mm: skip several tests when thp is not available" (Chunyu
   Hu)

   Fix several issues in the selftests code which were causing breakage
   when the tests were run on CONFIG_THP=n kernels

 - "mm/mprotect: micro-optimization work" (Pedro Falcato)

   A couple of nice speedups for mprotect()

 - "MAINTAINERS: update KHO and LIVE UPDATE entries" (Pratyush Yadav)

   Document upcoming changes in the maintenance of KHO, LUO, memfd_luo,
   kexec, crash, kdump and probably other kexec-based things - they are
   being moved out of mm.git and into a new git tree

* tag 'mm-stable-2026-04-18-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (121 commits)
  MAINTAINERS: add page cache reviewer
  mm/vmscan: avoid false-positive -Wuninitialized warning
  MAINTAINERS: update Dave's kdump reviewer email address
  MAINTAINERS: drop include/linux/liveupdate from LIVE UPDATE
  MAINTAINERS: drop include/linux/kho/abi/ from KHO
  MAINTAINERS: update KHO and LIVE UPDATE maintainers
  MAINTAINERS: update kexec/kdump maintainers entries
  mm/migrate_device: remove dead migration entry check in migrate_vma_collect_huge_pmd()
  selftests: mm: skip charge_reserved_hugetlb without killall
  userfaultfd: allow registration of ranges below mmap_min_addr
  mm/vmstat: fix vmstat_shepherd double-scheduling vmstat_update
  mm/hugetlb: fix early boot crash on parameters without '=' separator
  zram: reject unrecognized type= values in recompress_store()
  docs: proc: document ProtectionKey in smaps
  mm/mprotect: special-case small folios when applying permissions
  mm/mprotect: move softleaf code out of the main function
  mm: remove '!root_reclaim' checking in should_abort_scan()
  mm/sparse: fix comment for section map alignment
  mm/page_io: use sio->len for PSWPIN accounting in sio_read_complete()
  selftests/mm: transhuge_stress: skip the test when thp not available
  ...
2026-04-19 08:01:17 -07:00
Mike Rapoport (Microsoft)andAndrew Morton f74991b4e3 shmem, userfaultfd: implement shmem uffd operations using vm_uffd_ops
Add filemap_add() and filemap_remove() methods to vm_uffd_ops and use them
in __mfill_atomic_pte() to add shmem folios to page cache and remove them
in case of error.

Implement these methods in shmem along with vm_uffd_ops->alloc_folio() and
drop shmem_mfill_atomic_pte().

Since userfaultfd now does not reference any functions from shmem, drop
include if linux/shmem_fs.h from mm/userfaultfd.c

mfill_atomic_install_pte() is not used anywhere outside of mm/userfaultfd,
make it static.

Link: https://lore.kernel.org/20260402041156.1377214-11-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: James Houghton <jthoughton@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrei Vagin <avagin@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand (Arm) <david@kernel.org>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Harry Yoo (Oracle) <harry@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nikita Kalyazin <kalyazin@amazon.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Carlier <devnexen@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:54 -07:00
Mike Rapoport (Microsoft)andAndrew Morton dfc4d77182 shmem, userfaultfd: use a VMA callback to handle UFFDIO_CONTINUE
When userspace resolves a page fault in a shmem VMA with UFFDIO_CONTINUE
it needs to get a folio that already exists in the pagecache backing that
VMA.

Instead of using shmem_get_folio() for that, add a get_folio_noalloc()
method to 'struct vm_uffd_ops' that will return a folio if it exists in
the VMA's pagecache at given pgoff.

Implement get_folio_noalloc() method for shmem and slightly refactor
userfaultfd's mfill_get_vma() and mfill_atomic_pte_continue() to support
this new API.

Link: https://lore.kernel.org/20260402041156.1377214-9-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: James Houghton <jthoughton@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrei Vagin <avagin@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand (Arm) <david@kernel.org>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Harry Yoo (Oracle) <harry@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nikita Kalyazin <kalyazin@amazon.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Carlier <devnexen@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:54 -07:00
Mike Rapoport (Microsoft)andAndrew Morton 0f48947c42 userfaultfd: introduce vm_uffd_ops
Current userfaultfd implementation works only with memory managed by core
MM: anonymous, shmem and hugetlb.

First, there is no fundamental reason to limit userfaultfd support only to
the core memory types and userfaults can be handled similarly to regular
page faults provided a VMA owner implements appropriate callbacks.

Second, historically various code paths were conditioned on
vma_is_anonymous(), vma_is_shmem() and is_vm_hugetlb_page() and some of
these conditions can be expressed as operations implemented by a
particular memory type.

Introduce vm_uffd_ops extension to vm_operations_struct that will delegate
memory type specific operations to a VMA owner.

Operations for anonymous memory are handled internally in userfaultfd
using anon_uffd_ops that implicitly assigned to anonymous VMAs.

Start with a single operation, ->can_userfault() that will verify that a
VMA meets requirements for userfaultfd support at registration time.

Implement that method for anonymous, shmem and hugetlb and move relevant
parts of vma_can_userfault() into the new callbacks.

[rppt@kernel.org: relocate VM_DROPPABLE test, per Tal]
  Link: https://lore.kernel.org/adffgfM5ANxtPIEF@kernel.org
Link: https://lore.kernel.org/20260402041156.1377214-8-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrei Vagin <avagin@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand (Arm) <david@kernel.org>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Harry Yoo (Oracle) <harry@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nikita Kalyazin <kalyazin@amazon.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Carlier <devnexen@gmail.com>
Cc: Tal Zussman <tz2294@columbia.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:53 -07:00
Linus Torvalds 334fbe734e Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:

 - "maple_tree: Replace big node with maple copy" (Liam Howlett)

   Mainly prepararatory work for ongoing development but it does reduce
   stack usage and is an improvement.

 - "mm, swap: swap table phase III: remove swap_map" (Kairui Song)

   Offers memory savings by removing the static swap_map. It also yields
   some CPU savings and implements several cleanups.

 - "mm: memfd_luo: preserve file seals" (Pratyush Yadav)

   File seal preservation to LUO's memfd code

 - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
   Chen)

   Additional userspace stats reportng to zswap

 - "arch, mm: consolidate empty_zero_page" (Mike Rapoport)

   Some cleanups for our handling of ZERO_PAGE() and zero_pfn

 - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
   Han)

   A robustness improvement and some cleanups in the kmemleak code

 - "Improve khugepaged scan logic" (Vernon Yang)

   Improve khugepaged scan logic and reduce CPU consumption by
   prioritizing scanning tasks that access memory frequently

 - "Make KHO Stateless" (Jason Miu)

   Simplify Kexec Handover by transitioning KHO from an xarray-based
   metadata tracking system with serialization to a radix tree data
   structure that can be passed directly to the next kernel

 - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
   Ballasi and Steven Rostedt)

   Enhance vmscan's tracepointing

 - "mm: arch/shstk: Common shadow stack mapping helper and
   VM_NOHUGEPAGE" (Catalin Marinas)

   Cleanup for the shadow stack code: remove per-arch code in favour of
   a generic implementation

 - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)

   Fix a WARN() which can be emitted the KHO restores a vmalloc area

 - "mm: Remove stray references to pagevec" (Tal Zussman)

   Several cleanups, mainly udpating references to "struct pagevec",
   which became folio_batch three years ago

 - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
   Shutsemau)

   Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
   pages encode their relationship to the head page

 - "mm/damon/core: improve DAMOS quota efficiency for core layer
   filters" (SeongJae Park)

   Improve two problematic behaviors of DAMOS that makes it less
   efficient when core layer filters are used

 - "mm/damon: strictly respect min_nr_regions" (SeongJae Park)

   Improve DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter

 - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)

   The proper fix for a previously hotfixed SMP=n issue. Code
   simplifications and cleanups ensued

 - "mm: cleanups around unmapping / zapping" (David Hildenbrand)

   A bunch of cleanups around unmapping and zapping. Mostly
   simplifications, code movements, documentation and renaming of
   zapping functions

 - "support batched checking of the young flag for MGLRU" (Baolin Wang)

   Batched checking of the young flag for MGLRU. It's part cleanups; one
   benchmark shows large performance benefits for arm64

 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)

   memcg cleanup and robustness improvements

 - "Allow order zero pages in page reporting" (Yuvraj Sakshith)

   Enhance free page reporting - it is presently and undesirably order-0
   pages when reporting free memory.

 - "mm: vma flag tweaks" (Lorenzo Stoakes)

   Cleanup work following from the recent conversion of the VMA flags to
   a bitmap

 - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
   Park)

   Add some more developer-facing debug checks into DAMON core

 - "mm/damon: test and document power-of-2 min_region_sz requirement"
   (SeongJae Park)

   An additional DAMON kunit test and makes some adjustments to the
   addr_unit parameter handling

 - "mm/damon/core: make passed_sample_intervals comparisons
   overflow-safe" (SeongJae Park)

   Fix a hard-to-hit time overflow issue in DAMON core

 - "mm/damon: improve/fixup/update ratio calculation, test and
   documentation" (SeongJae Park)

   A batch of misc/minor improvements and fixups for DAMON

 - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
   Hildenbrand)

   Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
   movement was required.

 - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)

   A somewhat random mix of fixups, recompression cleanups and
   improvements in the zram code

 - "mm/damon: support multiple goal-based quota tuning algorithms"
   (SeongJae Park)

   Extend DAMOS quotas goal auto-tuning to support multiple tuning
   algorithms that users can select

 - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)

   Fix the khugpaged sysfs handling so we no longer spam the logs with
   reams of junk when starting/stopping khugepaged

 - "mm: improve map count checks" (Lorenzo Stoakes)

   Provide some cleanups and slight fixes in the mremap, mmap and vma
   code

 - "mm/damon: support addr_unit on default monitoring targets for
   modules" (SeongJae Park)

   Extend the use of DAMON core's addr_unit tunable

 - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)

   Cleanups to khugepaged and is a base for Nico's planned khugepaged
   mTHP support

 - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)

   Code movement and cleanups in the memhotplug and sparsemem code

 - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
   CONFIG_MIGRATION" (David Hildenbrand)

   Rationalize some memhotplug Kconfig support

 - "change young flag check functions to return bool" (Baolin Wang)

   Cleanups to change all young flag check functions to return bool

 - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
   Law and SeongJae Park)

   Fix a few potential DAMON bugs

 - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
   Stoakes)

   Convert a lot of the existing use of the legacy vm_flags_t data type
   to the new vma_flags_t type which replaces it. Mainly in the vma
   code.

 - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)

   Expand the mmap_prepare functionality, which is intended to replace
   the deprecated f_op->mmap hook which has been the source of bugs and
   security issues for some time. Cleanups, documentation, extension of
   mmap_prepare into filesystem drivers

 - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)

   Simplify and clean up zap_huge_pmd(). Additional cleanups around
   vm_normal_folio_pmd() and the softleaf functionality are performed.

* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm: fix deferred split queue races during migration
  mm/khugepaged: fix issue with tracking lock
  mm/huge_memory: add and use has_deposited_pgtable()
  mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
  mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
  mm/huge_memory: separate out the folio part of zap_huge_pmd()
  mm/huge_memory: use mm instead of tlb->mm
  mm/huge_memory: remove unnecessary sanity checks
  mm/huge_memory: deduplicate zap deposited table call
  mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
  mm/huge_memory: add a common exit path to zap_huge_pmd()
  mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
  mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
  mm/huge: avoid big else branch in zap_huge_pmd()
  mm/huge_memory: simplify vma_is_specal_huge()
  mm: on remap assert that input range within the proposed VMA
  mm: add mmap_action_map_kernel_pages[_full]()
  uio: replace deprecated mmap hook with mmap_prepare in uio_info
  drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
  mm: allow handling of stacked mmap_prepare hooks in more drivers
  ...
2026-04-15 12:59:16 -07:00
Nico PacheandAndrew Morton b90c453d26 mm: introduce is_pmd_order helper
In order to add mTHP support to khugepaged, we will often be checking if a
given order is (or is not) a PMD order.  Some places in the kernel already
use this check, so lets create a simple helper function to keep the code
clean and readable.

Link: https://lkml.kernel.org/r/20260325114022.444081-3-npache@redhat.com
Signed-off-by: Nico Pache <npache@redhat.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Dev Jain <dev.jain@arm.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Barry Song <baohua@kernel.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rafael Aquini <raquini@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shivank Garg <shivankg@amd.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Takashi Iwai (SUSE) <tiwai@suse.de>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <yang@os.amperecomputing.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:29 -07:00
Lorenzo Stoakes (Oracle)andAndrew Morton 5e6d45d720 mm: reintroduce vma_flags_test() as a singular flag test
Since we've now renamed vma_flags_test() to vma_flags_test_any() to be
very clear as to what we are in fact testing, we now have the opportunity
to bring vma_flags_test() back, but for explicitly testing a single VMA
flag.

This is useful, as often flag tests are against a single flag, and
vma_flags_test_any(flags, VMA_READ_BIT) reads oddly and potentially causes
confusion.

We use sparse to enforce that users won't accidentally pass vm_flags_t to
this function without it being flagged so this should make it harder to
get this wrong.

Of course, passing vma_flags_t to the function is impossible, as it is a
struct.

Also update the VMA tests to reflect this change.

Link: https://lkml.kernel.org/r/f33f8d7f16c3f3d286a1dc2cba12c23683073134.1772704455.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Babu Moger <babu.moger@amd.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Chatre, Reinette <reinette.chatre@intel.com>
Cc: Chunhai Guo <guochunhai@vivo.com>
Cc: Damien Le Maol <dlemoal@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hongbo Li <lihongbo22@huawei.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: James Morse <james.morse@arm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jeffle Xu <jefflexu@linux.alibaba.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naohiro Aota <naohiro.aota@wdc.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Sandeep Dhavale <dhavale@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Yue Hu <zbestahu@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:18 -07:00
Lorenzo Stoakes (Oracle)andAndrew Morton e650bb30ca mm: rename VMA flag helpers to be more readable
Patch series "mm: vma flag tweaks".

The ongoing work around introducing non-system word VMA flags has
introduced a number of helper functions and macros to make life easier
when working with these flags and to make conversions from the legacy use
of VM_xxx flags more straightforward.

This series improves these to reduce confusion as to what they do and to
improve consistency and readability.

Firstly the series renames vma_flags_test() to vma_flags_test_any() to
make it abundantly clear that this function tests whether any of the flags
are set (as opposed to vma_flags_test_all()).

It then renames vma_desc_test_flags() to vma_desc_test_any() for the same
reason.  Note that we drop the 'flags' suffix here, as
vma_desc_test_any_flags() would be cumbersome and 'test' implies a flag
test.

Similarly, we rename vma_test_all_flags() to vma_test_all() for
consistency.

Next, we have a couple of instances (erofs, zonefs) where we are now
testing for vma_desc_test_any(desc, VMA_SHARED_BIT) &&
vma_desc_test_any(desc, VMA_MAYWRITE_BIT).

This is silly, so this series introduces vma_desc_test_all() so these
callers can instead invoke vma_desc_test_all(desc, VMA_SHARED_BIT,
VMA_MAYWRITE_BIT).

We then observe that quite a few instances of vma_flags_test_any() and
vma_desc_test_any() are in fact only testing against a single flag.

Using the _any() variant here is just confusing - 'any' of single item
reads strangely and is liable to cause confusion.

So in these instances the series reintroduces vma_flags_test() and
vma_desc_test() as helpers which test against a single flag.

The fact that vma_flags_t is a struct and that vma_flag_t utilises sparse
to avoid confusion with vm_flags_t makes it impossible for a user to
misuse these helpers without it getting flagged somewhere.

The series also updates __mk_vma_flags() and functions invoked by it to
explicitly mark them always inline to match expectation and to be
consistent with other VMA flag helpers.

It also renames vma_flag_set() to vma_flags_set_flag() (a function only
used by __mk_vma_flags()) to be consistent with other VMA flag helpers.

Finally it updates the VMA tests for each of these changes, and introduces
explicit tests for vma_flags_test() and vma_desc_test() to assert that
they behave as expected.


This patch (of 6):

On reflection, it's confusing to have vma_flags_test() and
vma_desc_test_flags() test whether any comma-separated VMA flag bit is
set, while also having vma_flags_test_all() and vma_test_all_flags()
separately test whether all flags are set.

Firstly, rename vma_flags_test() to vma_flags_test_any() to eliminate this
confusion.

Secondly, since the VMA descriptor flag functions are becoming rather
cumbersome, prefer vma_desc_test*() to vma_desc_test_flags*(), and also
rename vma_desc_test_flags() to vma_desc_test_any().

Finally, rename vma_test_all_flags() to vma_test_all() to keep the
VMA-specific helper consistent with the VMA descriptor naming convention
and to help avoid confusion vs.  vma_flags_test_all().

While we're here, also update whitespace to be consistent in helper
functions.

Link: https://lkml.kernel.org/r/cover.1772704455.git.ljs@kernel.org
Link: https://lkml.kernel.org/r/0f9cb3c511c478344fac0b3b3b0300bb95be95e9.1772704455.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Suggested-by: Pedro Falcato <pfalcato@suse.de>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Babu Moger <babu.moger@amd.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Chatre, Reinette <reinette.chatre@intel.com>
Cc: Chunhai Guo <guochunhai@vivo.com>
Cc: Damien Le Maol <dlemoal@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hongbo Li <lihongbo22@huawei.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: James Morse <james.morse@arm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jeffle Xu <jefflexu@linux.alibaba.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naohiro Aota <naohiro.aota@wdc.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Sandeep Dhavale <dhavale@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Yue Hu <zbestahu@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:18 -07:00
Tal ZussmanandAndrew Morton 511f04aac4 folio_batch: rename PAGEVEC_SIZE to FOLIO_BATCH_SIZE
struct pagevec no longer exists.  Rename the macro appropriately.

Link: https://lkml.kernel.org/r/20260225-pagevec_cleanup-v2-4-716868cc2d11@columbia.edu
Signed-off-by: Tal Zussman <tz2294@columbia.edu>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:07 -07:00
Tal ZussmanandAndrew Morton 4e1d77a8f3 folio_batch: rename pagevec.h to folio_batch.h
struct pagevec was removed in commit 1e0877d58b ("mm: remove struct
pagevec").  Rename include/linux/pagevec.h to reflect reality and update
includes tree-wide.  Add the new filename to MAINTAINERS explicitly, as it
no longer matches the "include/linux/page[-_]*" pattern in MEMORY
MANAGEMENT - CORE.

Link: https://lkml.kernel.org/r/20260225-pagevec_cleanup-v2-3-716868cc2d11@columbia.edu
Signed-off-by: Tal Zussman <tz2294@columbia.edu>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:07 -07:00
Kairui SongandAndrew Morton 7498bddab9 mm/shmem: remove unnecessary restrain unmask of swap gfp flags
The comment makes it look like copy-paste leftovers from
shmem_replace_folio.  The first try of the swap doesn't always have a
limited zone.

So don't drop the restraint, which should make the GFP more accurate.

Link: https://lkml.kernel.org/r/20260211-shmem-swap-gfp-v1-1-e9781099a861@tencent.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:01 -07:00
Christian Brauner 52b364fed6 shmem: adapt to rhashtable-based simple_xattrs with lazy allocation
Adapt tmpfs/shmem to use the rhashtable-based xattr path and switch
from an embedded struct to pointer-based lazy allocation.

Change shmem_inode_info.xattrs from embedded 'struct simple_xattrs' to
a pointer 'struct simple_xattrs *', initialized to NULL. This avoids
the rhashtable overhead for every tmpfs inode, which helps when a lot of
inodes exist.

The xattr store is allocated on first use:

- shmem_initxattrs(): Allocates via simple_xattrs_alloc() when
  security modules set initial xattrs during inode creation.

- shmem_xattr_handler_set(): Allocates on first setxattr, with a
  short-circuit for removal when no xattrs are stored yet.

All read paths (shmem_xattr_handler_get, shmem_listxattr) check for
NULL xattrs pointer and return -ENODATA or 0 respectively.

Replaced xattr entries are freed via simple_xattr_free_rcu() to allow
concurrent RCU readers to finish.

shmem_evict_inode() conditionally frees the xattr store only when
allocated.

Also change simple_xattr_add() from void to int to propagate
rhashtable insertion failures. shmem_initxattrs() is the only caller.

Link: https://patch.msgid.link/20260216-work-xattr-socket-v1-3-c2efa4f74cb7@kernel.org
Acked-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-23 13:06:38 +01:00
Christian Brauner b32c4a2136 xattr: add rhashtable-based simple_xattr infrastructure
Add rhashtable support to the simple_xattr subsystem while keeping the
existing rbtree code fully functional. This allows consumers to be
migrated one at a time without breaking any intermediate build.

struct simple_xattrs gains a dispatch flag and a union holding either
the rbtree (rb_root + rwlock) or rhashtable state:

  struct simple_xattrs {
      bool use_rhashtable;
      union {
          struct { struct rb_root rb_root; rwlock_t lock; };
          struct rhashtable ht;
      };
  };

simple_xattrs_init() continues to set up the rbtree path for existing
embedded-struct callers.

Add simple_xattrs_alloc() which dynamically allocates a simple_xattrs
and initializes the rhashtable path. This is the entry point for
consumers switching to pointer-based lazy allocation.

The five core functions (get, set, list, add, free) dispatch based on
the use_rhashtable flag.

Existing callers continue to use the rbtree path unchanged. As each
consumer is converted it will switch to simple_xattrs_alloc() and the
rhashtable path. Once all consumers are converted a follow-up patch
will remove the rbtree code.

Link: https://patch.msgid.link/20260216-work-xattr-socket-v1-2-c2efa4f74cb7@kernel.org
Acked-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-23 13:06:38 +01:00
Linus Torvalds bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook 69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Linus Torvalds eeccf287a2 Merge tag 'mm-stable-2026-02-18-19-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more MM  updates from Andrew Morton:

 - "mm/vmscan: fix demotion targets checks in reclaim/demotion" fixes a
   couple of issues in the demotion code - pages were failed demotion
   and were finding themselves demoted into disallowed nodes (Bing Jiao)

 - "Remove XA_ZERO from error recovery of dup_mmap()" fixes a rare
   mapledtree race and performs a number of cleanups (Liam Howlett)

 - "mm: add bitmap VMA flag helpers and convert all mmap_prepare to use
   them" implements a lot of cleanups following on from the conversion
   of the VMA flags into a bitmap (Lorenzo Stoakes)

 - "support batch checking of references and unmapping for large folios"
   implements batching to greatly improve the performance of reclaiming
   clean file-backed large folios (Baolin Wang)

 - "selftests/mm: add memory failure selftests" does as claimed (Miaohe
   Lin)

* tag 'mm-stable-2026-02-18-19-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (36 commits)
  mm/page_alloc: clear page->private in free_pages_prepare()
  selftests/mm: add memory failure dirty pagecache test
  selftests/mm: add memory failure clean pagecache test
  selftests/mm: add memory failure anonymous page test
  mm: rmap: support batched unmapping for file large folios
  arm64: mm: implement the architecture-specific clear_flush_young_ptes()
  arm64: mm: support batch clearing of the young flag for large folios
  arm64: mm: factor out the address and ptep alignment into a new helper
  mm: rmap: support batched checks of the references for large folios
  tools/testing/vma: add VMA userland tests for VMA flag functions
  tools/testing/vma: separate out vma_internal.h into logical headers
  tools/testing/vma: separate VMA userland tests into separate files
  mm: make vm_area_desc utilise vma_flags_t only
  mm: update all remaining mmap_prepare users to use vma_flags_t
  mm: update shmem_[kernel]_file_*() functions to use vma_flags_t
  mm: update secretmem to use VMA flags on mmap_prepare
  mm: update hugetlbfs to use VMA flags on mmap_prepare
  mm: add basic VMA flag operation helper functions
  tools: bitmap: add missing bitmap_[subset(), andnot()]
  mm: add mk_vma_flags() bitmap flag macro helper
  ...
2026-02-18 20:50:32 -08:00
Lorenzo StoakesandAndrew Morton 590d356aa4 mm: update shmem_[kernel]_file_*() functions to use vma_flags_t
In order to be able to use only vma_flags_t in vm_area_desc we must adjust
shmem file setup functions to operate in terms of vma_flags_t rather than
vm_flags_t.

This patch makes this change and updates all callers to use the new
functions.

No functional changes intended.

[akpm@linux-foundation.org: comment fixes, per Baolin]
Link: https://lkml.kernel.org/r/736febd280eb484d79cef5cf55b8a6f79ad832d2.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-12 15:42:58 -08:00
Linus Torvalds 4cff5c05e0 Merge tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:

 - "powerpc/64s: do not re-activate batched TLB flush" makes
   arch_{enter|leave}_lazy_mmu_mode() nest properly (Alexander Gordeev)

   It adds a generic enter/leave layer and switches architectures to use
   it. Various hacks were removed in the process.

 - "zram: introduce compressed data writeback" implements data
   compression for zram writeback (Richard Chang and Sergey Senozhatsky)

 - "mm: folio_zero_user: clear page ranges" adds clearing of contiguous
   page ranges for hugepages. Large improvements during demand faulting
   are demonstrated (David Hildenbrand)

 - "memcg cleanups" tidies up some memcg code (Chen Ridong)

 - "mm/damon: introduce {,max_}nr_snapshots and tracepoint for damos
   stats" improves DAMOS stat's provided information, deterministic
   control, and readability (SeongJae Park)

 - "selftests/mm: hugetlb cgroup charging: robustness fixes" fixes a few
   issues in the hugetlb cgroup charging selftests (Li Wang)

 - "Fix va_high_addr_switch.sh test failure - again" addresses several
   issues in the va_high_addr_switch test (Chunyu Hu)

 - "mm/damon/tests/core-kunit: extend existing test scenarios" improves
   the KUnit test coverage for DAMON (Shu Anzai)

 - "mm/khugepaged: fix dirty page handling for MADV_COLLAPSE" fixes a
   glitch in khugepaged which was causing madvise(MADV_COLLAPSE) to
   transiently return -EAGAIN (Shivank Garg)

 - "arch, mm: consolidate hugetlb early reservation" reworks and
   consolidates a pile of straggly code related to reservation of
   hugetlb memory from bootmem and creation of CMA areas for hugetlb
   (Mike Rapoport)

 - "mm: clean up anon_vma implementation" cleans up the anon_vma
   implementation in various ways (Lorenzo Stoakes)

 - "tweaks for __alloc_pages_slowpath()" does a little streamlining of
   the page allocator's slowpath code (Vlastimil Babka)

 - "memcg: separate private and public ID namespaces" cleans up the
   memcg ID code and prevents the internal-only private IDs from being
   exposed to userspace (Shakeel Butt)

 - "mm: hugetlb: allocate frozen gigantic folio" cleans up the
   allocation of frozen folios and avoids some atomic refcount
   operations (Kefeng Wang)

 - "mm/damon: advance DAMOS-based LRU sorting" improves DAMOS's movement
   of memory betewwn the active and inactive LRUs and adds auto-tuning
   of the ratio-based quotas and of monitoring intervals (SeongJae Park)

 - "Support page table check on PowerPC" makes
   CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc (Andrew Donnellan)

 - "nodemask: align nodes_and{,not} with underlying bitmap ops" makes
   nodes_and() and nodes_andnot() propagate the return values from the
   underlying bit operations, enabling some cleanup in calling code
   (Yury Norov)

 - "mm/damon: hide kdamond and kdamond_lock from API callers" cleans up
   some DAMON internal interfaces (SeongJae Park)

 - "mm/khugepaged: cleanups and scan limit fix" does some cleanup work
   in khupaged and fixes a scan limit accounting issue (Shivank Garg)

 - "mm: balloon infrastructure cleanups" goes to town on the balloon
   infrastructure and its page migration function. Mainly cleanups, also
   some locking simplification (David Hildenbrand)

 - "mm/vmscan: add tracepoint and reason for kswapd_failures reset" adds
   additional tracepoints to the page reclaim code (Jiayuan Chen)

 - "Replace wq users and add WQ_PERCPU to alloc_workqueue() users" is
   part of Marco's kernel-wide migration from the legacy workqueue APIs
   over to the preferred unbound workqueues (Marco Crivellari)

 - "Various mm kselftests improvements/fixes" provides various unrelated
   improvements/fixes for the mm kselftests (Kevin Brodsky)

 - "mm: accelerate gigantic folio allocation" greatly speeds up gigantic
   folio allocation, mainly by avoiding unnecessary work in
   pfn_range_valid_contig() (Kefeng Wang)

 - "selftests/damon: improve leak detection and wss estimation
   reliability" improves the reliability of two of the DAMON selftests
   (SeongJae Park)

 - "mm/damon: cleanup kdamond, damon_call(), damos filter and
   DAMON_MIN_REGION" does some cleanup work in the core DAMON code
   (SeongJae Park)

 - "Docs/mm/damon: update intro, modules, maintainer profile, and misc"
   performs maintenance work on the DAMON documentation (SeongJae Park)

 - "mm: add and use vma_assert_stabilised() helper" refactors and cleans
   up the core VMA code. The main aim here is to be able to use the mmap
   write lock's lockdep state to perform various assertions regarding
   the locking which the VMA code requires (Lorenzo Stoakes)

 - "mm, swap: swap table phase II: unify swapin use" removes some old
   swap code (swap cache bypassing and swap synchronization) which
   wasn't working very well. Various other cleanups and simplifications
   were made. The end result is a 20% speedup in one benchmark (Kairui
   Song)

 - "enable PT_RECLAIM on more 64-bit architectures" makes PT_RECLAIM
   available on 64-bit alpha, loongarch, mips, parisc, and um. Various
   cleanups were performed along the way (Qi Zheng)

* tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (325 commits)
  mm/memory: handle non-split locks correctly in zap_empty_pte_table()
  mm: move pte table reclaim code to memory.c
  mm: make PT_RECLAIM depends on MMU_GATHER_RCU_TABLE_FREE
  mm: convert __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config
  um: mm: enable MMU_GATHER_RCU_TABLE_FREE
  parisc: mm: enable MMU_GATHER_RCU_TABLE_FREE
  mips: mm: enable MMU_GATHER_RCU_TABLE_FREE
  LoongArch: mm: enable MMU_GATHER_RCU_TABLE_FREE
  alpha: mm: enable MMU_GATHER_RCU_TABLE_FREE
  mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h
  mm/damon/stat: remove __read_mostly from memory_idle_ms_percentiles
  zsmalloc: make common caches global
  mm: add SPDX id lines to some mm source files
  mm/zswap: use %pe to print error pointers
  mm/vmscan: use %pe to print error pointers
  mm/readahead: fix typo in comment
  mm: khugepaged: fix NR_FILE_PAGES and NR_SHMEM in collapse_file()
  mm: refactor vma_map_pages to use vm_insert_pages
  mm/damon: unify address range representation with damon_addr_range
  mm/cma: replace snprintf with strscpy in cma_new_area
  ...
2026-02-12 11:32:37 -08:00
Linus Torvalds aa2a0fcd4c Merge tag 'vfs-7.0-rc1.leases' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs lease updates from Christian Brauner:
 "This contains updates for lease support to require filesystems to
  explicitly opt-in to lease support

  Currently kernel_setlease() falls through to generic_setlease() when a
  a filesystem does not define ->setlease(), silently granting lease
  support to every filesystem regardless of whether it is prepared for
  it.

  This is a poor default: most filesystems never intended to support
  leases, and the silent fallthrough makes it impossible to distinguish
  "supports leases" from "never thought about it".

  This inverts the default. It adds explicit

	.setlease = generic_setlease;

  assignments to every in-tree filesystem that should retain lease
  support, then changes kernel_setlease() to return -EINVAL when
  ->setlease is NULL.

  With the new default in place, simple_nosetlease() is redundant and
  is removed along with all references to it"

* tag 'vfs-7.0-rc1.leases' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (25 commits)
  fuse: add setlease file operation
  fs: remove simple_nosetlease()
  filelock: default to returning -EINVAL when ->setlease operation is NULL
  xfs: add setlease file operation
  ufs: add setlease file operation
  udf: add setlease file operation
  tmpfs: add setlease file operation
  squashfs: add setlease file operation
  overlayfs: add setlease file operation
  orangefs: add setlease file operation
  ocfs2: add setlease file operation
  ntfs3: add setlease file operation
  nilfs2: add setlease file operation
  jfs: add setlease file operation
  jffs2: add setlease file operation
  gfs2: add a setlease file operation
  fat: add setlease file operation
  f2fs: add setlease file operation
  exfat: add setlease file operation
  ext4: add setlease file operation
  ...
2026-02-09 11:59:07 -08:00
Tim BirdandAndrew Morton ef24e0aa07 mm: add SPDX id lines to some mm source files
Some of the memory management source files are missing
SPDX-License-Identifier lines.  Add appropriate IDs
to these files (mostly GPL-2.0, but one LGPL-2.1).

Link: https://lkml.kernel.org/r/20260204213101.1754183-1-tim.bird@sony.com
Signed-off-by: Tim Bird <tim.bird@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-06 15:47:16 -08:00
Kairui SongandAndrew Morton 2030dddf95 mm, shmem: prevent infinite loop on truncate race
When truncating a large swap entry, shmem_free_swap() returns 0 when the
entry's index doesn't match the given index due to lookup alignment.  The
failure fallback path checks if the entry crosses the end border and
aborts when it happens, so truncate won't erase an unexpected entry or
range.  But one scenario was ignored.

When `index` points to the middle of a large swap entry, and the large
swap entry doesn't go across the end border, find_get_entries() will
return that large swap entry as the first item in the batch with
`indices[0]` equal to `index`.  The entry's base index will be smaller
than `indices[0]`, so shmem_free_swap() will fail and return 0 due to the
"base < index" check.  The code will then call shmem_confirm_swap(), get
the order, check if it crosses the END boundary (which it doesn't), and
retry with the same index.

The next iteration will find the same entry again at the same index with
same indices, leading to an infinite loop.

Fix this by retrying with a round-down index, and abort if the index is
smaller than the truncate range.

Link: https://lkml.kernel.org/r/aXo6ltB5iqAKJzY8@KASONG-MC4
Fixes: 809bc86517 ("mm: shmem: support large folio swap out")
Fixes: 8a1968bd99 ("mm/shmem, swap: fix race of truncate and swap entry split")
Signed-off-by: Kairui Song <kasong@tencent.com>
Reported-by: Chris Mason <clm@meta.com>
Closes: https://lore.kernel.org/linux-mm/20260128130336.727049-1-clm@meta.com/
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-02 18:43:55 -08:00
Kairui SongandAndrew Morton 3697615914 mm, swap: cleanup swap entry management workflow
The current swap entry allocation/freeing workflow has never had a clear
definition.  This makes it hard to debug or add new optimizations.

This commit introduces a proper definition of how swap entries would be
allocated and freed.  Now, most operations are folio based, so they will
never exceed one swap cluster, and we now have a cleaner border between
swap and the rest of mm, making it much easier to follow and debug,
especially with new added sanity checks.  Also making more optimization
possible.

Swap entry will be mostly freed and free with a folio bound.  The folio
lock will be useful for resolving many swap related races.

Now swap allocation (except hibernation) always starts with a folio in the
swap cache, and gets duped/freed protected by the folio lock:

- folio_alloc_swap() - The only allocation entry point now.
  Context: The folio must be locked.
  This allocates one or a set of continuous swap slots for a folio and
  binds them to the folio by adding the folio to the swap cache. The
  swap slots' swap count start with zero value.

- folio_dup_swap() - Increase the swap count of one or more entries.
  Context: The folio must be locked and in the swap cache. For now, the
  caller still has to lock the new swap entry owner (e.g., PTL).
  This increases the ref count of swap entries allocated to a folio.
  Newly allocated swap slots' count has to be increased by this helper
  as the folio got unmapped (and swap entries got installed).

- folio_put_swap() - Decrease the swap count of one or more entries.
  Context: The folio must be locked and in the swap cache. For now, the
  caller still has to lock the new swap entry owner (e.g., PTL).
  This decreases the ref count of swap entries allocated to a folio.
  Typically, swapin will decrease the swap count as the folio got
  installed back and the swap entry got uninstalled

  This won't remove the folio from the swap cache and free the
  slot. Lazy freeing of swap cache is helpful for reducing IO.
  There is already a folio_free_swap() for immediate cache reclaim.
  This part could be further optimized later.

The above locking constraints could be further relaxed when the swap table
is fully implemented.  Currently dup still needs the caller to lock the
swap entry container (e.g.  PTL), or a concurrent zap may underflow the
swap count.

Some swap users need to interact with swap count without involving folio
(e.g.  forking/zapping the page table or mapping truncate without swapin).
In such cases, the caller has to ensure there is no race condition on
whatever owns the swap count and use the below helpers:

- swap_put_entries_direct() - Decrease the swap count directly.
  Context: The caller must lock whatever is referencing the slots to
  avoid a race.

  Typically the page table zapping or shmem mapping truncate will need
  to free swap slots directly. If a slot is cached (has a folio bound),
  this will also try to release the swap cache.

- swap_dup_entry_direct() - Increase the swap count directly.
  Context: The caller must lock whatever is referencing the entries to
  avoid race, and the entries must already have a swap count > 1.

  Typically, forking will need to copy the page table and hence needs to
  increase the swap count of the entries in the table. The page table is
  locked while referencing the swap entries, so the entries all have a
  swap count > 1 and can't be freed.

Hibernation subsystem is a bit different, so two special wrappers are here:

- swap_alloc_hibernation_slot() - Allocate one entry from one device.
- swap_free_hibernation_slot() - Free one entry allocated by the above
  helper.

All hibernation entries are exclusive to the hibernation subsystem and
should not interact with ordinary swap routines.

By separating the workflows, it will be possible to bind folio more
tightly with swap cache and get rid of the SWAP_HAS_CACHE as a temporary
pin.

This commit should not introduce any behavior change

[kasong@tencent.com: fix leak, per Chris Mason.  Remove WARN_ON, per Lai Yi]
  Link: https://lkml.kernel.org/r/CAMgjq7AUz10uETVm8ozDWcB3XohkOqf0i33KGrAquvEVvfp5cg@mail.gmail.com
[ryncsn@gmail.com: fix KSM copy pages for swapoff, per Chris]
  Link: https://lkml.kernel.org/r/aXxkANcET3l2Xu6J@KASONG-MC4
Link: https://lkml.kernel.org/r/20251220-swap-table-p2-v5-14-8862a265a033@tencent.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Signed-off-by: Kairui Song <ryncsn@gmail.com>
Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Yosry Ahmed <yosry.ahmed@linux.dev>
Cc: Deepanshu Kartikey <kartikey406@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Chris Mason <clm@fb.com>
Cc: Chris Mason <clm@meta.com>
Cc: Lai Yi <yi1.lai@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-31 14:22:56 -08:00
Nhat PhamandAndrew Morton bc617c990e mm/shmem, swap: remove SWAP_MAP_SHMEM
The SWAP_MAP_SHMEM state was introduced in the commit aaa468653b
("swap_info: note SWAP_MAP_SHMEM"), to quickly determine if a swap entry
belongs to shmem during swapoff.

However, swapoff has since been rewritten in the commit b56a2d8af9 ("mm:
rid swapoff of quadratic complexity").  Now having swap count ==
SWAP_MAP_SHMEM value is basically the same as having swap count == 1, and
swap_shmem_alloc() behaves analogously to swap_duplicate().  The only
difference of note is that swap_shmem_alloc() does not check for -ENOMEM
returned from __swap_duplicate(), but it is OK because shmem never
re-duplicates any swap entry it owns.  This will stil be safe if we use
(batched) swap_duplicate() instead.

This commit adds swap_duplicate_nr(), the batched variant of
swap_duplicate(), and removes the SWAP_MAP_SHMEM state and the associated
swap_shmem_alloc() helper to simplify the state machine (both mentally and
in terms of actual code).  We will also have an extra state/special value
that can be repurposed (for swap entries that never gets re-duplicated).

Link: https://lkml.kernel.org/r/20251220-swap-table-p2-v5-8-8862a265a033@tencent.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Cc: Yosry Ahmed <yosry.ahmed@linux.dev>
Cc: Deepanshu Kartikey <kartikey406@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kairui Song <ryncsn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-31 14:22:55 -08:00
Kairui SongandAndrew Morton c246d236b1 mm/shmem: never bypass the swap cache for SWP_SYNCHRONOUS_IO
Now the overhead of the swap cache is trivial to none, bypassing the swap
cache is no longer a good optimization.

We have removed the cache bypass swapin for anon memory, now do the same
for shmem.  Many helpers and functions can be dropped now.

The performance may slightly drop because of the co-existence and double
update of swap_map and swap table, and this problem will be improved very
soon in later commits by dropping the swap_map update partially:

Swapin of 24 GB file with tmpfs with
transparent_hugepage_tmpfs=within_size and ZRAM, 3 test runs on my
machine:

Before:  After this commit:  After this series:
5.99s    6.29s               6.08s

And later swap table phases will drop the swap_map completely to avoid
overhead and reduce memory usage.

Link: https://lkml.kernel.org/r/20251219195751.61328-1-ryncsn@gmail.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Cc: Yosry Ahmed <yosry.ahmed@linux.dev>
Cc: Deepanshu Kartikey <kartikey406@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-31 14:22:54 -08:00
Andrew Morton f84b65b045 Merge branch 'mm-hotfixes-stable' into mm-stable to pick up "mm/shmem,
swap: fix race of truncate and swap entry split", needed for merging "mm,
swap: cleanup swap entry management workflow".
2026-01-31 14:20:03 -08:00