<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/mm/hmm.c, branch v7.1</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v7.1</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v7.1'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2026-03-20T11:05:56+00:00</updated>
<entry>
<title>mm/hmm: Indicate that HMM requires DMA coherency</title>
<updated>2026-03-20T11:05:56+00:00</updated>
<author>
<name>Leon Romanovsky</name>
<email>leonro@nvidia.com</email>
</author>
<published>2026-03-16T19:06:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f5ebf241c407dbf629fcf515015e139fcea2c2f0'/>
<id>urn:sha1:f5ebf241c407dbf629fcf515015e139fcea2c2f0</id>
<content type='text'>
HMM is fundamentally about allowing a sophisticated device to perform DMA
directly to a process’s memory while the CPU accesses that same memory at
the same time. It is similar to SVA but does not rely on IOMMU support.
Because the entire model depends on concurrent access to shared memory, it
fails as a uAPI if SWIOTLB substitutes the memory or if the CPU caches are
not coherent with DMA.

Until now, there has been no reliable way to report this, and various
approximations have been used:

int hmm_dma_map_alloc(struct device *dev, struct hmm_dma_map *map,
                      size_t nr_entries, size_t dma_entry_size)
{
&lt;...&gt;
        /*
         * The HMM API violates our normal DMA buffer ownership rules and can't
         * transfer buffer ownership.  The dma_addressing_limited() check is a
         * best approximation to ensure no swiotlb buffering happens.
         */
        dma_need_sync = !dev-&gt;dma_skip_sync;
        if (dma_need_sync || dma_addressing_limited(dev))
                return -EOPNOTSUPP;

So let's mark mapped buffers with DMA_ATTR_REQUIRE_COHERENT attribute
to prevent silent data corruption if someone tries to use hmm in a system
with swiotlb or incoherent DMA

Reviewed-by: Jason Gunthorpe &lt;jgg@nvidia.com&gt;
Signed-off-by: Leon Romanovsky &lt;leonro@nvidia.com&gt;
Signed-off-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Link: https://lore.kernel.org/r/20260316-dma-debug-overlap-v3-8-1dde90a7f08b@nvidia.com
</content>
</entry>
<entry>
<title>treewide: Replace kmalloc with kmalloc_obj for non-scalar types</title>
<updated>2026-02-21T09:02:28+00:00</updated>
<author>
<name>Kees Cook</name>
<email>kees@kernel.org</email>
</author>
<published>2026-02-21T07:49:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=69050f8d6d075dc01af7a5f2f550a8067510366f'/>
<id>urn:sha1:69050f8d6d075dc01af7a5f2f550a8067510366f</id>
<content type='text'>
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 &lt;kees@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2025-12-05T21:52:43+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-12-05T21:52:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=7203ca412fc8e8a0588e9adc0f777d3163f8dff3'/>
<id>urn:sha1:7203ca412fc8e8a0588e9adc0f777d3163f8dff3</id>
<content type='text'>
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-&gt;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 -&gt;mmap() over to -&gt;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-&gt;__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
  ...
</content>
</entry>
<entry>
<title>mm: eliminate further swapops predicates</title>
<updated>2025-11-24T23:08:52+00:00</updated>
<author>
<name>Lorenzo Stoakes</name>
<email>lorenzo.stoakes@oracle.com</email>
</author>
<published>2025-11-10T22:21:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=93976a20345b4aff1ac7598ec1223d65ca33d49c'/>
<id>urn:sha1:93976a20345b4aff1ac7598ec1223d65ca33d49c</id>
<content type='text'>
Having converted so much of the code base to software leaf entries, we can
mop up some remaining cases.

We replace is_pfn_swap_entry(), pfn_swap_entry_to_page(),
is_writable_device_private_entry(), is_device_exclusive_entry(),
is_migration_entry(), is_writable_migration_entry(),
is_readable_migration_entry(), swp_offset_pfn() and pfn_swap_entry_folio()
with softleaf equivalents.

No functional change intended.

Link: https://lkml.kernel.org/r/956bc9c031604811c0070d2f4bf2f1373f230213.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Alistair Popple &lt;apopple@nvidia.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Axel Rasmussen &lt;axelrasmussen@google.com&gt;
Cc: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Barry Song &lt;baohua@kernel.org&gt;
Cc: Byungchul Park &lt;byungchul@sk.com&gt;
Cc: Chengming Zhou &lt;chengming.zhou@linux.dev&gt;
Cc: Chris Li &lt;chrisl@kernel.org&gt;
Cc: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Claudio Imbrenda &lt;imbrenda@linux.ibm.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Cc: Gregory Price &lt;gourry@gourry.net&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: "Huang, Ying" &lt;ying.huang@linux.alibaba.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: Jann Horn &lt;jannh@google.com&gt;
Cc: Janosch Frank &lt;frankja@linux.ibm.com&gt;
Cc: Jason Gunthorpe &lt;jgg@ziepe.ca&gt;
Cc: Joshua Hahn &lt;joshua.hahnjy@gmail.com&gt;
Cc: Kairui Song &lt;kasong@tencent.com&gt;
Cc: Kemeng Shi &lt;shikemeng@huaweicloud.com&gt;
Cc: Lance Yang &lt;lance.yang@linux.dev&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Mathew Brost &lt;matthew.brost@intel.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Muchun Song &lt;muchun.song@linux.dev&gt;
Cc: Naoya Horiguchi &lt;nao.horiguchi@gmail.com&gt;
Cc: Nhat Pham &lt;nphamcs@gmail.com&gt;
Cc: Nico Pache &lt;npache@redhat.com&gt;
Cc: Oscar Salvador &lt;osalvador@suse.de&gt;
Cc: Pasha Tatashin &lt;pasha.tatashin@soleen.com&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Rakie Kim &lt;rakie.kim@sk.com&gt;
Cc: Rik van Riel &lt;riel@surriel.com&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: SeongJae Park &lt;sj@kernel.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Wei Xu &lt;weixugc@google.com&gt;
Cc: xu xin &lt;xu.xin16@zte.com.cn&gt;
Cc: Yuanchu Xie &lt;yuanchu@google.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm: remove non_swap_entry() and use softleaf helpers instead</title>
<updated>2025-11-24T23:08:51+00:00</updated>
<author>
<name>Lorenzo Stoakes</name>
<email>lorenzo.stoakes@oracle.com</email>
</author>
<published>2025-11-10T22:21:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=9ff30bb9ab40b34908eefd661f12f99aa00d04c3'/>
<id>urn:sha1:9ff30bb9ab40b34908eefd661f12f99aa00d04c3</id>
<content type='text'>
There is simply no need for the hugely confusing concept of 'non-swap'
swap entries now we have the concept of softleaf entries and relevant
softleaf_xxx() helpers.

Adjust all callers to use these instead and remove non_swap_entry()
altogether.

No functional change intended.

Link: https://lkml.kernel.org/r/2562093f37f4a9cffea0447058014485eb50aaaf.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Alistair Popple &lt;apopple@nvidia.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Axel Rasmussen &lt;axelrasmussen@google.com&gt;
Cc: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Barry Song &lt;baohua@kernel.org&gt;
Cc: Byungchul Park &lt;byungchul@sk.com&gt;
Cc: Chengming Zhou &lt;chengming.zhou@linux.dev&gt;
Cc: Chris Li &lt;chrisl@kernel.org&gt;
Cc: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Claudio Imbrenda &lt;imbrenda@linux.ibm.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Cc: Gregory Price &lt;gourry@gourry.net&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: "Huang, Ying" &lt;ying.huang@linux.alibaba.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: Jann Horn &lt;jannh@google.com&gt;
Cc: Janosch Frank &lt;frankja@linux.ibm.com&gt;
Cc: Jason Gunthorpe &lt;jgg@ziepe.ca&gt;
Cc: Joshua Hahn &lt;joshua.hahnjy@gmail.com&gt;
Cc: Kairui Song &lt;kasong@tencent.com&gt;
Cc: Kemeng Shi &lt;shikemeng@huaweicloud.com&gt;
Cc: Lance Yang &lt;lance.yang@linux.dev&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Mathew Brost &lt;matthew.brost@intel.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Muchun Song &lt;muchun.song@linux.dev&gt;
Cc: Naoya Horiguchi &lt;nao.horiguchi@gmail.com&gt;
Cc: Nhat Pham &lt;nphamcs@gmail.com&gt;
Cc: Nico Pache &lt;npache@redhat.com&gt;
Cc: Oscar Salvador &lt;osalvador@suse.de&gt;
Cc: Pasha Tatashin &lt;pasha.tatashin@soleen.com&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Rakie Kim &lt;rakie.kim@sk.com&gt;
Cc: Rik van Riel &lt;riel@surriel.com&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: SeongJae Park &lt;sj@kernel.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Wei Xu &lt;weixugc@google.com&gt;
Cc: xu xin &lt;xu.xin16@zte.com.cn&gt;
Cc: Yuanchu Xie &lt;yuanchu@google.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm: replace pmd_to_swp_entry() with softleaf_from_pmd()</title>
<updated>2025-11-24T23:08:51+00:00</updated>
<author>
<name>Lorenzo Stoakes</name>
<email>lorenzo.stoakes@oracle.com</email>
</author>
<published>2025-11-10T22:21:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=0ac881efe16468503e8c1e7d8a7210b75f027ce3'/>
<id>urn:sha1:0ac881efe16468503e8c1e7d8a7210b75f027ce3</id>
<content type='text'>
Introduce softleaf_from_pmd() to do the equivalent operation for PMDs that
softleaf_from_pte() fulfils, and cascade changes through code base
accordingly, introducing helpers as necessary.

We are then able to eliminate pmd_to_swp_entry(),
is_pmd_migration_entry(), is_pmd_device_private_entry() and
is_pmd_non_present_folio_entry().

This further establishes the use of leaf operations throughout the code
base and further establishes the foundations for eliminating
is_swap_pmd().

No functional change intended.

[lorenzo.stoakes@oracle.com: check writable, not readable/writable, per Vlastimil]
  Link: https://lkml.kernel.org/r/cd97b6ec-00f9-45a4-9ae0-8f009c212a94@lucifer.local
Link: https://lkml.kernel.org/r/3fb431699639ded8fdc63d2210aa77a38c8891f1.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Reviewed-by: SeongJae Park &lt;sj@kernel.org&gt;\
Reviewed-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Alistair Popple &lt;apopple@nvidia.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Axel Rasmussen &lt;axelrasmussen@google.com&gt;
Cc: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Barry Song &lt;baohua@kernel.org&gt;
Cc: Byungchul Park &lt;byungchul@sk.com&gt;
Cc: Chengming Zhou &lt;chengming.zhou@linux.dev&gt;
Cc: Chris Li &lt;chrisl@kernel.org&gt;
Cc: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Claudio Imbrenda &lt;imbrenda@linux.ibm.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Cc: Gregory Price &lt;gourry@gourry.net&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: "Huang, Ying" &lt;ying.huang@linux.alibaba.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: Jann Horn &lt;jannh@google.com&gt;
Cc: Janosch Frank &lt;frankja@linux.ibm.com&gt;
Cc: Jason Gunthorpe &lt;jgg@ziepe.ca&gt;
Cc: Joshua Hahn &lt;joshua.hahnjy@gmail.com&gt;
Cc: Kairui Song &lt;kasong@tencent.com&gt;
Cc: Kemeng Shi &lt;shikemeng@huaweicloud.com&gt;
Cc: Lance Yang &lt;lance.yang@linux.dev&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Mathew Brost &lt;matthew.brost@intel.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Muchun Song &lt;muchun.song@linux.dev&gt;
Cc: Naoya Horiguchi &lt;nao.horiguchi@gmail.com&gt;
Cc: Nhat Pham &lt;nphamcs@gmail.com&gt;
Cc: Nico Pache &lt;npache@redhat.com&gt;
Cc: Oscar Salvador &lt;osalvador@suse.de&gt;
Cc: Pasha Tatashin &lt;pasha.tatashin@soleen.com&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Rakie Kim &lt;rakie.kim@sk.com&gt;
Cc: Rik van Riel &lt;riel@surriel.com&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Wei Xu &lt;weixugc@google.com&gt;
Cc: xu xin &lt;xu.xin16@zte.com.cn&gt;
Cc: Yuanchu Xie &lt;yuanchu@google.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm: introduce leaf entry type and use to simplify leaf entry logic</title>
<updated>2025-11-24T23:08:50+00:00</updated>
<author>
<name>Lorenzo Stoakes</name>
<email>lorenzo.stoakes@oracle.com</email>
</author>
<published>2025-11-10T22:21:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=68aa2fdbf57f769e552f472ddb762aba028a207e'/>
<id>urn:sha1:68aa2fdbf57f769e552f472ddb762aba028a207e</id>
<content type='text'>
The kernel maintains leaf page table entries which contain either:

The kernel maintains leaf page table entries which contain either:

 - Nothing ('none' entries)
 - Present entries*
 - Everything else that will cause a fault which the kernel handles

* Present entries are either entries the hardware can navigate without page
  fault or special cases like NUMA hint protnone or PMD with cleared
  present bit which contain hardware-valid entries modulo the present bit.

In the 'everything else' group we include swap entries, but we also
include a number of other things such as migration entries, device private
entries and marker entries.

Unfortunately this 'everything else' group expresses everything through a
swp_entry_t type, and these entries are referred to swap entries even
though they may well not contain a...  swap entry.

This is compounded by the rather mind-boggling concept of a non-swap swap
entry (checked via non_swap_entry()) and the means by which we twist and
turn to satisfy this.

This patch lays the foundation for reducing this confusion.

We refer to 'everything else' as a 'software-define leaf entry' or
'softleaf'.  for short And in fact we scoop up the 'none' entries into
this concept also so we are left with:

- Present entries.
- Softleaf entries (which may be empty).

This allows for radical simplification across the board - one can simply
convert any leaf page table entry to a leaf entry via softleaf_from_pte().

If the entry is present, we return an empty leaf entry, so it is assumed
the caller is aware that they must differentiate between the two
categories of page table entries, checking for the former via
pte_present().

As a result, we can eliminate a number of places where we would otherwise
need to use predicates to see if we can proceed with leaf page table entry
conversion and instead just go ahead and do it unconditionally.

We do so where we can, adjusting surrounding logic as necessary to
integrate the new softleaf_t logic as far as seems reasonable at this
stage.

We typedef swp_entry_t to softleaf_t for the time being until the
conversion can be complete, meaning everything remains compatible
regardless of which type is used.  We will eventually remove swp_entry_t
when the conversion is complete.

We introduce a new header file to keep things clear - leafops.h - this
imports swapops.h so can direct replace swapops imports without issue, and
we do so in all the files that require it.

Additionally, add new leafops.h file to core mm maintainers entry.

Link: https://lkml.kernel.org/r/c879383aac77d96a03e4d38f7daba893cd35fc76.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Acked-by: Zi Yan &lt;ziy@nvidia.com&gt;
Reviewed-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Alistair Popple &lt;apopple@nvidia.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Axel Rasmussen &lt;axelrasmussen@google.com&gt;
Cc: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Barry Song &lt;baohua@kernel.org&gt;
Cc: Byungchul Park &lt;byungchul@sk.com&gt;
Cc: Chengming Zhou &lt;chengming.zhou@linux.dev&gt;
Cc: Chris Li &lt;chrisl@kernel.org&gt;
Cc: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Claudio Imbrenda &lt;imbrenda@linux.ibm.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Cc: Gregory Price &lt;gourry@gourry.net&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: "Huang, Ying" &lt;ying.huang@linux.alibaba.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: Jann Horn &lt;jannh@google.com&gt;
Cc: Janosch Frank &lt;frankja@linux.ibm.com&gt;
Cc: Jason Gunthorpe &lt;jgg@ziepe.ca&gt;
Cc: Joshua Hahn &lt;joshua.hahnjy@gmail.com&gt;
Cc: Kairui Song &lt;kasong@tencent.com&gt;
Cc: Kemeng Shi &lt;shikemeng@huaweicloud.com&gt;
Cc: Lance Yang &lt;lance.yang@linux.dev&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Mathew Brost &lt;matthew.brost@intel.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Muchun Song &lt;muchun.song@linux.dev&gt;
Cc: Naoya Horiguchi &lt;nao.horiguchi@gmail.com&gt;
Cc: Nhat Pham &lt;nphamcs@gmail.com&gt;
Cc: Nico Pache &lt;npache@redhat.com&gt;
Cc: Oscar Salvador &lt;osalvador@suse.de&gt;
Cc: Pasha Tatashin &lt;pasha.tatashin@soleen.com&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Rakie Kim &lt;rakie.kim@sk.com&gt;
Cc: Rik van Riel &lt;riel@surriel.com&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: SeongJae Park &lt;sj@kernel.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Wei Xu &lt;weixugc@google.com&gt;
Cc: xu xin &lt;xu.xin16@zte.com.cn&gt;
Cc: Yuanchu Xie &lt;yuanchu@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm: correctly handle UFFD PTE markers</title>
<updated>2025-11-24T23:08:50+00:00</updated>
<author>
<name>Lorenzo Stoakes</name>
<email>lorenzo.stoakes@oracle.com</email>
</author>
<published>2025-11-10T22:21:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c093cf451094a9a03c4d4929bc30122a53038b7b'/>
<id>urn:sha1:c093cf451094a9a03c4d4929bc30122a53038b7b</id>
<content type='text'>
Patch series "mm: remove is_swap_[pte, pmd]() + non-swap entries,
introduce leaf entries", v3.

There's an established convention in the kernel that we treat leaf page
tables (so far at the PTE, PMD level) as containing 'swap entries' should
they be neither empty (i.e.  p**_none() evaluating true) nor present (i.e.
p**_present() evaluating true).

However, at the same time we also have helper predicates - is_swap_pte(),
is_swap_pmd() - which are inconsistently used.

This is problematic, as it is logical to assume that should somebody wish
to operate upon a page table swap entry they should first check to see if
it is in fact one.

It also implies that perhaps, in future, we might introduce a non-present,
none page table entry that is not a swap entry.

This series resolves this issue by systematically eliminating all use of
the is_swap_pte() and is swap_pmd() predicates so we retain only the
convention that should a leaf page table entry be neither none nor present
it is a swap entry.

We also have the further issue that 'swap entry' is unfortunately a really
rather overloaded term and in fact refers to both entries for swap and for
other information such as migration entries, page table markers, and
device private entries.

We therefore have the rather 'unique' concept of a 'non-swap' swap entry.

This series therefore introduces the concept of 'software leaf entries',
of type softleaf_t, to eliminate this confusion.

A software leaf entry in this sense is any page table entry which is
non-present, and represented by the softleaf_t type.  That is - page table
leaf entries which are software-controlled by the kernel.

This includes 'none' or empty entries, which are simply represented by an
zero leaf entry value.

In order to maintain compatibility as we transition the kernel to this new
type, we simply typedef swp_entry_t to softleaf_t.

We introduce a number of predicates and helpers to interact with software
leaf entries in include/linux/leafops.h which, as it imports swapops.h,
can be treated as a drop-in replacement for swapops.h wherever leaf entry
helpers are used.

Since softleaf_from_[pte, pmd]() treats present entries as they were
empty/none leaf entries, this allows for a great deal of simplification of
code throughout the code base, which this series utilises a great deal.

We additionally change from swap entry to software leaf entry handling
where it makes sense to and eliminate functions from swapops.h where
software leaf entries obviate the need for the functions.


This patch (of 16):

PTE markers were previously only concerned with UFFD-specific logic - that
is, PTE entries with the UFFD WP marker set or those marked via
UFFDIO_POISON.

However since the introduction of guard markers in commit 7c53dfbdb024
("mm: add PTE_MARKER_GUARD PTE marker"), this has no longer been the case.

Issues have been avoided as guard regions are not permitted in conjunction
with UFFD, but it still leaves very confusing logic in place, most notably
the misleading and poorly named pte_none_mostly() and
huge_pte_none_mostly().

This predicate returns true for PTE entries that ought to be treated as
none, but only in certain circumstances, and on the assumption we are
dealing with H/W poison markers or UFFD WP markers.

This patch removes these functions and makes each invocation of these
functions instead explicitly check what it needs to check.

As part of this effort it introduces is_uffd_pte_marker() to explicitly
determine if a marker in fact is used as part of UFFD or not.

In the HMM logic we note that the only time we would need to check for a
fault is in the case of a UFFD WP marker, otherwise we simply encounter a
fault error (VM_FAULT_HWPOISON for H/W poisoned marker, VM_FAULT_SIGSEGV
for a guard marker), so only check for the UFFD WP case.

While we're here we also refactor code to make it easier to understand.

[akpm@linux-foundation.org: fix comment typo, per Mike]
Link: https://lkml.kernel.org/r/cover.1762812360.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/c38625fd9a1c1f1cf64ae8a248858e45b3dcdf11.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Reviewed-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Reviewed-by: Mike Rapoport (Microsoft) &lt;rppt@kernel.org&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Alistair Popple &lt;apopple@nvidia.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Axel Rasmussen &lt;axelrasmussen@google.com&gt;
Cc: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Barry Song &lt;baohua@kernel.org&gt;
Cc: Byungchul Park &lt;byungchul@sk.com&gt;
Cc: Chengming Zhou &lt;chengming.zhou@linux.dev&gt;
Cc: Chris Li &lt;chrisl@kernel.org&gt;
Cc: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Claudio Imbrenda &lt;imbrenda@linux.ibm.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Cc: Gregory Price &lt;gourry@gourry.net&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: "Huang, Ying" &lt;ying.huang@linux.alibaba.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: Jann Horn &lt;jannh@google.com&gt;
Cc: Janosch Frank &lt;frankja@linux.ibm.com&gt;
Cc: Jason Gunthorpe &lt;jgg@ziepe.ca&gt;
Cc: Joshua Hahn &lt;joshua.hahnjy@gmail.com&gt;
Cc: Kairui Song &lt;kasong@tencent.com&gt;
Cc: Kemeng Shi &lt;shikemeng@huaweicloud.com&gt;
Cc: Lance Yang &lt;lance.yang@linux.dev&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Mathew Brost &lt;matthew.brost@intel.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Muchun Song &lt;muchun.song@linux.dev&gt;
Cc: Naoya Horiguchi &lt;nao.horiguchi@gmail.com&gt;
Cc: Nhat Pham &lt;nphamcs@gmail.com&gt;
Cc: Nico Pache &lt;npache@redhat.com&gt;
Cc: Oscar Salvador &lt;osalvador@suse.de&gt;
Cc: Pasha Tatashin &lt;pasha.tatashin@soleen.com&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Rakie Kim &lt;rakie.kim@sk.com&gt;
Cc: Rik van Riel &lt;riel@surriel.com&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: SeongJae Park &lt;sj@kernel.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Wei Xu &lt;weixugc@google.com&gt;
Cc: xu xin &lt;xu.xin16@zte.com.cn&gt;
Cc: Yuanchu Xie &lt;yuanchu@google.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>PCI/P2PDMA: Simplify bus address mapping API</title>
<updated>2025-11-20T19:01:41+00:00</updated>
<author>
<name>Leon Romanovsky</name>
<email>leonro@nvidia.com</email>
</author>
<published>2025-11-20T09:28:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d4504262f745e48c1739c8b864f779b4b0f9de80'/>
<id>urn:sha1:d4504262f745e48c1739c8b864f779b4b0f9de80</id>
<content type='text'>
Update the pci_p2pdma_bus_addr_map() function to take a direct pointer
to the p2pdma_provider structure instead of the pci_p2pdma_map_state.
This simplifies the API by removing the need for callers to extract
the provider from the state structure.

The change updates all callers across the kernel (block layer, IOMMU,
DMA direct, and HMM) to pass the provider pointer directly, making
the code more explicit and reducing unnecessary indirection. This
also removes the runtime warning check since callers now have direct
control over which provider they use.

Tested-by: Alex Mastro &lt;amastro@fb.com&gt;
Tested-by: Nicolin Chen &lt;nicolinc@nvidia.com&gt;
Signed-off-by: Leon Romanovsky &lt;leonro@nvidia.com&gt;
Acked-by: Ankit Agrawal &lt;ankita@nvidia.com&gt;
Link: https://lore.kernel.org/r/20251120-dmabuf-vfio-v9-2-d7f71607f371@nvidia.com
Signed-off-by: Alex Williamson &lt;alex@shazbot.org&gt;
</content>
</entry>
<entry>
<title>mm: replace READ_ONCE() with standard page table accessors</title>
<updated>2025-11-17T01:27:56+00:00</updated>
<author>
<name>Anshuman Khandual</name>
<email>anshuman.khandual@arm.com</email>
</author>
<published>2025-10-07T06:31:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c0efdb373c3aaacb32db59cadb0710cac13e44ae'/>
<id>urn:sha1:c0efdb373c3aaacb32db59cadb0710cac13e44ae</id>
<content type='text'>
Replace all READ_ONCE() with a standard page table accessors i.e
pxdp_get() that defaults into READ_ONCE() in cases where platform does not
override.

Link: https://lkml.kernel.org/r/20251007063100.2396936-1-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual &lt;anshuman.khandual@arm.com&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Reviewed-by: Lance Yang &lt;lance.yang@linux.dev&gt;
Reviewed-by: Wei Yang &lt;richard.weiyang@gmail.com&gt;
Reviewed-by: Dev Jain &lt;dev.jain@arm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
</feed>
