<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/mips/include, branch v6.16</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>mm: pgtable: fix pte_swp_exclusive</title>
<updated>2025-06-11T21:52:08+00:00</updated>
<author>
<name>Magnus Lindholm</name>
<email>linmag7@gmail.com</email>
</author>
<published>2025-02-18T17:55:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=403d1338a4a59cfebb4ded53fa35fbd5119f36b1'/>
<id>403d1338a4a59cfebb4ded53fa35fbd5119f36b1</id>
<content type='text'>
Make pte_swp_exclusive return bool instead of int.  This will better
reflect how pte_swp_exclusive is actually used in the code.

This fixes swap/swapoff problems on Alpha due pte_swp_exclusive not
returning correct values when _PAGE_SWP_EXCLUSIVE bit resides in upper
32-bits of PTE (like on alpha).

Suggested-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Magnus Lindholm &lt;linmag7@gmail.com&gt;
Cc: Sam James &lt;sam@gentoo.org&gt;
Link: https://lore.kernel.org/lkml/20250218175735.19882-2-linmag7@gmail.com/
Link: https://lore.kernel.org/lkml/20250602041118.GA2675383@ZenIV/
[ Applied as the 'sed' script Al suggested   - Linus ]
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Make pte_swp_exclusive return bool instead of int.  This will better
reflect how pte_swp_exclusive is actually used in the code.

This fixes swap/swapoff problems on Alpha due pte_swp_exclusive not
returning correct values when _PAGE_SWP_EXCLUSIVE bit resides in upper
32-bits of PTE (like on alpha).

Suggested-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Magnus Lindholm &lt;linmag7@gmail.com&gt;
Cc: Sam James &lt;sam@gentoo.org&gt;
Link: https://lore.kernel.org/lkml/20250218175735.19882-2-linmag7@gmail.com/
Link: https://lore.kernel.org/lkml/20250602041118.GA2675383@ZenIV/
[ Applied as the 'sed' script Al suggested   - Linus ]
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'mips_6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux</title>
<updated>2025-06-06T14:56:36+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-06-06T14:56:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=67faad74352d1ce0c1f411f92fdb1e0c0f3c9380'/>
<id>67faad74352d1ce0c1f411f92fdb1e0c0f3c9380</id>
<content type='text'>
Pull MIPS updates from Thomas Bogendoerfer:

 - Added support for EcoNet platform

 - Added support for parallel CPU bring up on EyeQ

 - Other cleanups and fixes

* tag 'mips_6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (23 commits)
  MIPS: loongson2ef: lemote-2f: add missing function prototypes
  MIPS: loongson2ef: cs5536: add missing function prototypes
  MIPS: SMP: Move the AP sync point before the calibration delay
  mips: econet: Fix incorrect Kconfig dependencies
  MAINTAINERS: Add entry for newly added EcoNet platform.
  mips: dts: Add EcoNet DTS with EN751221 and SmartFiber XP8421-B board
  dt-bindings: vendor-prefixes: Add SmartFiber
  mips: Add EcoNet MIPS platform support
  dt-bindings: mips: Add EcoNet platform binding
  MIPS: bcm63xx: nvram: avoid inefficient use of crc32_le_combine()
  mips: dts: pic32: pic32mzda: Rename the sdhci nodename to match with common mmc-controller binding
  MIPS: SMP: Move the AP sync point before the non-parallel aware functions
  MIPS: Replace strcpy() with strscpy() in vpe_elfload()
  MIPS: BCM63XX: Replace strcpy() with strscpy() in board_prom_init()
  mips: ptrace: Improve code formatting and indentation
  MIPS: SMP: Implement parallel CPU bring up for EyeQ
  mips: Add -std= flag specified in KBUILD_CFLAGS to vdso CFLAGS
  MIPS: Loongson64: Add missing '#interrupt-cells' for loongson64c_ls7a
  mips: dts: realtek: Add MDIO controller
  MIPS: txx9: gpio: use new line value setter callbacks
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull MIPS updates from Thomas Bogendoerfer:

 - Added support for EcoNet platform

 - Added support for parallel CPU bring up on EyeQ

 - Other cleanups and fixes

* tag 'mips_6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (23 commits)
  MIPS: loongson2ef: lemote-2f: add missing function prototypes
  MIPS: loongson2ef: cs5536: add missing function prototypes
  MIPS: SMP: Move the AP sync point before the calibration delay
  mips: econet: Fix incorrect Kconfig dependencies
  MAINTAINERS: Add entry for newly added EcoNet platform.
  mips: dts: Add EcoNet DTS with EN751221 and SmartFiber XP8421-B board
  dt-bindings: vendor-prefixes: Add SmartFiber
  mips: Add EcoNet MIPS platform support
  dt-bindings: mips: Add EcoNet platform binding
  MIPS: bcm63xx: nvram: avoid inefficient use of crc32_le_combine()
  mips: dts: pic32: pic32mzda: Rename the sdhci nodename to match with common mmc-controller binding
  MIPS: SMP: Move the AP sync point before the non-parallel aware functions
  MIPS: Replace strcpy() with strscpy() in vpe_elfload()
  MIPS: BCM63XX: Replace strcpy() with strscpy() in board_prom_init()
  mips: ptrace: Improve code formatting and indentation
  MIPS: SMP: Implement parallel CPU bring up for EyeQ
  mips: Add -std= flag specified in KBUILD_CFLAGS to vdso CFLAGS
  MIPS: Loongson64: Add missing '#interrupt-cells' for loongson64c_ls7a
  mips: dts: realtek: Add MDIO controller
  MIPS: txx9: gpio: use new line value setter callbacks
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2025-05-31T22:44:16+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-05-31T22:44:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=00c010e130e58301db2ea0cec1eadc931e1cb8cf'/>
<id>00c010e130e58301db2ea0cec1eadc931e1cb8cf</id>
<content type='text'>
Pull MM updates from Andrew Morton:

 - "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of
   creating a pte which addresses the first page in a folio and reduces
   the amount of plumbing which architecture must implement to provide
   this.

 - "Misc folio patches for 6.16" from Matthew Wilcox is a shower of
   largely unrelated folio infrastructure changes which clean things up
   and better prepare us for future work.

 - "memory,x86,acpi: hotplug memory alignment advisement" from Gregory
   Price adds early-init code to prevent x86 from leaving physical
   memory unused when physical address regions are not aligned to memory
   block size.

 - "mm/compaction: allow more aggressive proactive compaction" from
   Michal Clapinski provides some tuning of the (sadly, hard-coded (more
   sadly, not auto-tuned)) thresholds for our invokation of proactive
   compaction. In a simple test case, the reduction of a guest VM's
   memory consumption was dramatic.

 - "Minor cleanups and improvements to swap freeing code" from Kemeng
   Shi provides some code cleaups and a small efficiency improvement to
   this part of our swap handling code.

 - "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin
   adds the ability for a ptracer to modify syscalls arguments. At this
   time we can alter only "system call information that are used by
   strace system call tampering, namely, syscall number, syscall
   arguments, and syscall return value.

   This series should have been incorporated into mm.git's "non-MM"
   branch, but I goofed.

 - "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from
   Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl
   against /proc/pid/pagemap. This permits CRIU to more efficiently get
   at the info about guard regions.

 - "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan
   implements that fix. No runtime effect is expected because
   validate_page_before_insert() happens to fix up this error.

 - "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David
   Hildenbrand basically brings uprobe text poking into the current
   decade. Remove a bunch of hand-rolled implementation in favor of
   using more current facilities.

 - "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman
   Khandual provides enhancements and generalizations to the pte dumping
   code. This might be needed when 128-bit Page Table Descriptors are
   enabled for ARM.

 - "Always call constructor for kernel page tables" from Kevin Brodsky
   ensures that the ctor/dtor is always called for kernel pgtables, as
   it already is for user pgtables.

   This permits the addition of more functionality such as "insert hooks
   to protect page tables". This change does result in various
   architectures performing unnecesary work, but this is fixed up where
   it is anticipated to occur.

 - "Rust support for mm_struct, vm_area_struct, and mmap" from Alice
   Ryhl adds plumbing to permit Rust access to core MM structures.

 - "fix incorrectly disallowed anonymous VMA merges" from Lorenzo
   Stoakes takes advantage of some VMA merging opportunities which we've
   been missing for 15 years.

 - "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from
   SeongJae Park optimizes process_madvise()'s TLB flushing.

   Instead of flushing each address range in the provided iovec, we
   batch the flushing across all the iovec entries. The syscall's cost
   was approximately halved with a microbenchmark which was designed to
   load this particular operation.

 - "Track node vacancy to reduce worst case allocation counts" from
   Sidhartha Kumar makes the maple tree smarter about its node
   preallocation.

   stress-ng mmap performance increased by single-digit percentages and
   the amount of unnecessarily preallocated memory was dramaticelly
   reduced.

 - "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes
   a few unnecessary things which Baoquan noted when reading the code.

 - ""Enhance sysfs handling for memory hotplug in weighted interleave"
   from Rakie Kim "enhances the weighted interleave policy in the memory
   management subsystem by improving sysfs handling, fixing memory
   leaks, and introducing dynamic sysfs updates for memory hotplug
   support". Fixes things on error paths which we are unlikely to hit.

 - "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory"
   from SeongJae Park introduces new DAMOS quota goal metrics which
   eliminate the manual tuning which is required when utilizing DAMON
   for memory tiering.

 - "mm/vmalloc.c: code cleanup and improvements" from Baoquan He
   provides cleanups and small efficiency improvements which Baoquan
   found via code inspection.

 - "vmscan: enforce mems_effective during demotion" from Gregory Price
   changes reclaim to respect cpuset.mems_effective during demotion when
   possible. because presently, reclaim explicitly ignores
   cpuset.mems_effective when demoting, which may cause the cpuset
   settings to violated.

   This is useful for isolating workloads on a multi-tenant system from
   certain classes of memory more consistently.

 - "Clean up split_huge_pmd_locked() and remove unnecessary folio
   pointers" from Gavin Guo provides minor cleanups and efficiency gains
   in in the huge page splitting and migrating code.

 - "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache
   for `struct mem_cgroup', yielding improved memory utilization.

 - "add max arg to swappiness in memory.reclaim and lru_gen" from
   Zhongkun He adds a new "max" argument to the "swappiness=" argument
   for memory.reclaim MGLRU's lru_gen.

   This directs proactive reclaim to reclaim from only anon folios
   rather than file-backed folios.

 - "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the
   first step on the path to permitting the kernel to maintain existing
   VMs while replacing the host kernel via file-based kexec. At this
   time only memblock's reserve_mem is preserved.

 - "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides
   and uses a smarter way of looping over a pfn range. By skipping
   ranges of invalid pfns.

 - "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via
   cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning
   when a task is pinned a single NUMA mode.

   Dramatic performance benefits were seen in some real world cases.

 - "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank
   Garg addresses a warning which occurs during memory compaction when
   using JFS.

 - "move all VMA allocation, freeing and duplication logic to mm" from
   Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more
   appropriate mm/vma.c.

 - "mm, swap: clean up swap cache mapping helper" from Kairui Song
   provides code consolidation and cleanups related to the folio_index()
   function.

 - "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that.

 - "memcg: Fix test_memcg_min/low test failures" from Waiman Long
   addresses some bogus failures which are being reported by the
   test_memcontrol selftest.

 - "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo
   Stoakes commences the deprecation of file_operations.mmap() in favor
   of the new file_operations.mmap_prepare().

   The latter is more restrictive and prevents drivers from messing with
   things in ways which, amongst other problems, may defeat VMA merging.

 - "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples
   the per-cpu memcg charge cache from the objcg's one.

   This is a step along the way to making memcg and objcg charging
   NMI-safe, which is a BPF requirement.

 - "mm/damon: minor fixups and improvements for code, tests, and
   documents" from SeongJae Park is yet another batch of miscellaneous
   DAMON changes. Fix and improve minor problems in code, tests and
   documents.

 - "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg
   stats to be irq safe. Another step along the way to making memcg
   charging and stats updates NMI-safe, a BPF requirement.

 - "Let unmap_hugepage_range() and several related functions take folio
   instead of page" from Fan Ni provides folio conversions in the
   hugetlb code.

* tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits)
  mm: pcp: increase pcp-&gt;free_count threshold to trigger free_high
  mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range()
  mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page
  mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page
  mm/hugetlb: pass folio instead of page to unmap_ref_private()
  memcg: objcg stock trylock without irq disabling
  memcg: no stock lock for cpu hot-unplug
  memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs
  memcg: make count_memcg_events re-entrant safe against irqs
  memcg: make mod_memcg_state re-entrant safe against irqs
  memcg: move preempt disable to callers of memcg_rstat_updated
  memcg: memcg_rstat_updated re-entrant safe against irqs
  mm: khugepaged: decouple SHMEM and file folios' collapse
  selftests/eventfd: correct test name and improve messages
  alloc_tag: check mem_profiling_support in alloc_tag_init
  Docs/damon: update titles and brief introductions to explain DAMOS
  selftests/damon/_damon_sysfs: read tried regions directories in order
  mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject()
  mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat()
  mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull MM updates from Andrew Morton:

 - "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of
   creating a pte which addresses the first page in a folio and reduces
   the amount of plumbing which architecture must implement to provide
   this.

 - "Misc folio patches for 6.16" from Matthew Wilcox is a shower of
   largely unrelated folio infrastructure changes which clean things up
   and better prepare us for future work.

 - "memory,x86,acpi: hotplug memory alignment advisement" from Gregory
   Price adds early-init code to prevent x86 from leaving physical
   memory unused when physical address regions are not aligned to memory
   block size.

 - "mm/compaction: allow more aggressive proactive compaction" from
   Michal Clapinski provides some tuning of the (sadly, hard-coded (more
   sadly, not auto-tuned)) thresholds for our invokation of proactive
   compaction. In a simple test case, the reduction of a guest VM's
   memory consumption was dramatic.

 - "Minor cleanups and improvements to swap freeing code" from Kemeng
   Shi provides some code cleaups and a small efficiency improvement to
   this part of our swap handling code.

 - "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin
   adds the ability for a ptracer to modify syscalls arguments. At this
   time we can alter only "system call information that are used by
   strace system call tampering, namely, syscall number, syscall
   arguments, and syscall return value.

   This series should have been incorporated into mm.git's "non-MM"
   branch, but I goofed.

 - "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from
   Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl
   against /proc/pid/pagemap. This permits CRIU to more efficiently get
   at the info about guard regions.

 - "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan
   implements that fix. No runtime effect is expected because
   validate_page_before_insert() happens to fix up this error.

 - "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David
   Hildenbrand basically brings uprobe text poking into the current
   decade. Remove a bunch of hand-rolled implementation in favor of
   using more current facilities.

 - "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman
   Khandual provides enhancements and generalizations to the pte dumping
   code. This might be needed when 128-bit Page Table Descriptors are
   enabled for ARM.

 - "Always call constructor for kernel page tables" from Kevin Brodsky
   ensures that the ctor/dtor is always called for kernel pgtables, as
   it already is for user pgtables.

   This permits the addition of more functionality such as "insert hooks
   to protect page tables". This change does result in various
   architectures performing unnecesary work, but this is fixed up where
   it is anticipated to occur.

 - "Rust support for mm_struct, vm_area_struct, and mmap" from Alice
   Ryhl adds plumbing to permit Rust access to core MM structures.

 - "fix incorrectly disallowed anonymous VMA merges" from Lorenzo
   Stoakes takes advantage of some VMA merging opportunities which we've
   been missing for 15 years.

 - "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from
   SeongJae Park optimizes process_madvise()'s TLB flushing.

   Instead of flushing each address range in the provided iovec, we
   batch the flushing across all the iovec entries. The syscall's cost
   was approximately halved with a microbenchmark which was designed to
   load this particular operation.

 - "Track node vacancy to reduce worst case allocation counts" from
   Sidhartha Kumar makes the maple tree smarter about its node
   preallocation.

   stress-ng mmap performance increased by single-digit percentages and
   the amount of unnecessarily preallocated memory was dramaticelly
   reduced.

 - "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes
   a few unnecessary things which Baoquan noted when reading the code.

 - ""Enhance sysfs handling for memory hotplug in weighted interleave"
   from Rakie Kim "enhances the weighted interleave policy in the memory
   management subsystem by improving sysfs handling, fixing memory
   leaks, and introducing dynamic sysfs updates for memory hotplug
   support". Fixes things on error paths which we are unlikely to hit.

 - "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory"
   from SeongJae Park introduces new DAMOS quota goal metrics which
   eliminate the manual tuning which is required when utilizing DAMON
   for memory tiering.

 - "mm/vmalloc.c: code cleanup and improvements" from Baoquan He
   provides cleanups and small efficiency improvements which Baoquan
   found via code inspection.

 - "vmscan: enforce mems_effective during demotion" from Gregory Price
   changes reclaim to respect cpuset.mems_effective during demotion when
   possible. because presently, reclaim explicitly ignores
   cpuset.mems_effective when demoting, which may cause the cpuset
   settings to violated.

   This is useful for isolating workloads on a multi-tenant system from
   certain classes of memory more consistently.

 - "Clean up split_huge_pmd_locked() and remove unnecessary folio
   pointers" from Gavin Guo provides minor cleanups and efficiency gains
   in in the huge page splitting and migrating code.

 - "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache
   for `struct mem_cgroup', yielding improved memory utilization.

 - "add max arg to swappiness in memory.reclaim and lru_gen" from
   Zhongkun He adds a new "max" argument to the "swappiness=" argument
   for memory.reclaim MGLRU's lru_gen.

   This directs proactive reclaim to reclaim from only anon folios
   rather than file-backed folios.

 - "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the
   first step on the path to permitting the kernel to maintain existing
   VMs while replacing the host kernel via file-based kexec. At this
   time only memblock's reserve_mem is preserved.

 - "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides
   and uses a smarter way of looping over a pfn range. By skipping
   ranges of invalid pfns.

 - "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via
   cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning
   when a task is pinned a single NUMA mode.

   Dramatic performance benefits were seen in some real world cases.

 - "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank
   Garg addresses a warning which occurs during memory compaction when
   using JFS.

 - "move all VMA allocation, freeing and duplication logic to mm" from
   Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more
   appropriate mm/vma.c.

 - "mm, swap: clean up swap cache mapping helper" from Kairui Song
   provides code consolidation and cleanups related to the folio_index()
   function.

 - "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that.

 - "memcg: Fix test_memcg_min/low test failures" from Waiman Long
   addresses some bogus failures which are being reported by the
   test_memcontrol selftest.

 - "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo
   Stoakes commences the deprecation of file_operations.mmap() in favor
   of the new file_operations.mmap_prepare().

   The latter is more restrictive and prevents drivers from messing with
   things in ways which, amongst other problems, may defeat VMA merging.

 - "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples
   the per-cpu memcg charge cache from the objcg's one.

   This is a step along the way to making memcg and objcg charging
   NMI-safe, which is a BPF requirement.

 - "mm/damon: minor fixups and improvements for code, tests, and
   documents" from SeongJae Park is yet another batch of miscellaneous
   DAMON changes. Fix and improve minor problems in code, tests and
   documents.

 - "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg
   stats to be irq safe. Another step along the way to making memcg
   charging and stats updates NMI-safe, a BPF requirement.

 - "Let unmap_hugepage_range() and several related functions take folio
   instead of page" from Fan Ni provides folio conversions in the
   hugetlb code.

* tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits)
  mm: pcp: increase pcp-&gt;free_count threshold to trigger free_high
  mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range()
  mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page
  mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page
  mm/hugetlb: pass folio instead of page to unmap_ref_private()
  memcg: objcg stock trylock without irq disabling
  memcg: no stock lock for cpu hot-unplug
  memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs
  memcg: make count_memcg_events re-entrant safe against irqs
  memcg: make mod_memcg_state re-entrant safe against irqs
  memcg: move preempt disable to callers of memcg_rstat_updated
  memcg: memcg_rstat_updated re-entrant safe against irqs
  mm: khugepaged: decouple SHMEM and file folios' collapse
  selftests/eventfd: correct test name and improve messages
  alloc_tag: check mem_profiling_support in alloc_tag_init
  Docs/damon: update titles and brief introductions to explain DAMOS
  selftests/damon/_damon_sysfs: read tried regions directories in order
  mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject()
  mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat()
  mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: loongson2ef: lemote-2f: add missing function prototypes</title>
<updated>2025-05-30T12:19:02+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@infradead.org</email>
</author>
<published>2025-05-29T03:20:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5a0c749125c001cba673e9951b0002fba7ea2886'/>
<id>5a0c749125c001cba673e9951b0002fba7ea2886</id>
<content type='text'>
Add several missing function prototypes for lemote-2f to eliminate
build warnings:

arch/mips/loongson2ef/lemote-2f/machtype.c:10:13: warning: no previous prototype for 'mach_prom_init_machtype' [-Wmissing-prototypes]
   10 | void __init mach_prom_init_machtype(void)
arch/mips/loongson2ef/common/machtype.c:34:20: warning: no previous prototype for 'mach_prom_init_machtype' [-Wmissing-prototypes]
   34 | void __weak __init mach_prom_init_machtype(void)
arch/mips/loongson2ef/lemote-2f/pm.c:52:6: warning: no previous prototype for 'setup_wakeup_events' [-Wmissing-prototypes]
   52 | void setup_wakeup_events(void)
arch/mips/loongson2ef/lemote-2f/pm.c:90:5: warning: no previous prototype for 'wakeup_loongson' [-Wmissing-prototypes]
   90 | int wakeup_loongson(void)
arch/mips/loongson2ef/lemote-2f/pm.c:137:13: warning: no previous prototype for 'mach_suspend' [-Wmissing-prototypes]
  137 | void __weak mach_suspend(void)
arch/mips/loongson2ef/lemote-2f/pm.c:142:13: warning: no previous prototype for 'mach_resume' [-Wmissing-prototypes]
  142 | void __weak mach_resume(void)

Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Jiaxun Yang &lt;jiaxun.yang@flygoat.com&gt;
Cc: linux-mips@vger.kernel.org
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Signed-off-by: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add several missing function prototypes for lemote-2f to eliminate
build warnings:

arch/mips/loongson2ef/lemote-2f/machtype.c:10:13: warning: no previous prototype for 'mach_prom_init_machtype' [-Wmissing-prototypes]
   10 | void __init mach_prom_init_machtype(void)
arch/mips/loongson2ef/common/machtype.c:34:20: warning: no previous prototype for 'mach_prom_init_machtype' [-Wmissing-prototypes]
   34 | void __weak __init mach_prom_init_machtype(void)
arch/mips/loongson2ef/lemote-2f/pm.c:52:6: warning: no previous prototype for 'setup_wakeup_events' [-Wmissing-prototypes]
   52 | void setup_wakeup_events(void)
arch/mips/loongson2ef/lemote-2f/pm.c:90:5: warning: no previous prototype for 'wakeup_loongson' [-Wmissing-prototypes]
   90 | int wakeup_loongson(void)
arch/mips/loongson2ef/lemote-2f/pm.c:137:13: warning: no previous prototype for 'mach_suspend' [-Wmissing-prototypes]
  137 | void __weak mach_suspend(void)
arch/mips/loongson2ef/lemote-2f/pm.c:142:13: warning: no previous prototype for 'mach_resume' [-Wmissing-prototypes]
  142 | void __weak mach_resume(void)

Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Jiaxun Yang &lt;jiaxun.yang@flygoat.com&gt;
Cc: linux-mips@vger.kernel.org
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Signed-off-by: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: loongson2ef: cs5536: add missing function prototypes</title>
<updated>2025-05-30T12:18:33+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@infradead.org</email>
</author>
<published>2025-05-29T03:19:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=314da9d6b3119328c1a38234c68e720380d14957'/>
<id>314da9d6b3119328c1a38234c68e720380d14957</id>
<content type='text'>
Add missing function prototypes for cs5536, mostly for PCI functions,
and for init_mfgpt_clocksource().

arch/mips/loongson2ef/common/cs5536/cs5536_ide.c:15:6: warning: no previous prototype for 'pci_ide_write_reg' [-Wmissing-prototypes]
   15 | void pci_ide_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_ide.c:96:5: warning: no previous prototype for 'pci_ide_read_reg' [-Wmissing-prototypes]
   96 | u32 pci_ide_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_ehci.c:15:6: warning: no previous prototype for 'pci_ehci_write_reg' [-Wmissing-prototypes]
   15 | void pci_ehci_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_ehci.c:75:5: warning: no previous prototype for 'pci_ehci_read_reg' [-Wmissing-prototypes]
   75 | u32 pci_ehci_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_acc.c:15:6: warning: no previous prototype for 'pci_acc_write_reg' [-Wmissing-prototypes]
   15 | void pci_acc_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_acc.c:62:5: warning: no previous prototype for 'pci_acc_read_reg' [-Wmissing-prototypes]
   62 | u32 pci_acc_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_ohci.c:15:6: warning: no previous prototype for 'pci_ohci_write_reg' [-Wmissing-prototypes]
   15 | void pci_ohci_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_ohci.c:70:5: warning: no previous prototype for 'pci_ohci_read_reg' [-Wmissing-prototypes]
   70 | u32 pci_ohci_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_isa.c:84:6: warning: no previous prototype for 'pci_isa_write_bar' [-Wmissing-prototypes]
   84 | void pci_isa_write_bar(int n, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_isa.c:110:5: warning: no previous prototype for 'pci_isa_read_bar' [-Wmissing-prototypes]
  110 | u32 pci_isa_read_bar(int n)
arch/mips/loongson2ef/common/cs5536/cs5536_isa.c:134:6: warning: no previous prototype for 'pci_isa_write_reg' [-Wmissing-prototypes]
  134 | void pci_isa_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_isa.c:228:5: warning: no previous prototype for 'pci_isa_read_reg' [-Wmissing-prototypes]
  228 | u32 pci_isa_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_mfgpt.c:195:12: warning: no previous prototype for 'init_mfgpt_clocksource' [-Wmissing-prototypes]
  195 | int __init init_mfgpt_clocksource(void)

Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Jiaxun Yang &lt;jiaxun.yang@flygoat.com&gt;
Cc: linux-mips@vger.kernel.org
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Signed-off-by: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add missing function prototypes for cs5536, mostly for PCI functions,
and for init_mfgpt_clocksource().

arch/mips/loongson2ef/common/cs5536/cs5536_ide.c:15:6: warning: no previous prototype for 'pci_ide_write_reg' [-Wmissing-prototypes]
   15 | void pci_ide_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_ide.c:96:5: warning: no previous prototype for 'pci_ide_read_reg' [-Wmissing-prototypes]
   96 | u32 pci_ide_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_ehci.c:15:6: warning: no previous prototype for 'pci_ehci_write_reg' [-Wmissing-prototypes]
   15 | void pci_ehci_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_ehci.c:75:5: warning: no previous prototype for 'pci_ehci_read_reg' [-Wmissing-prototypes]
   75 | u32 pci_ehci_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_acc.c:15:6: warning: no previous prototype for 'pci_acc_write_reg' [-Wmissing-prototypes]
   15 | void pci_acc_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_acc.c:62:5: warning: no previous prototype for 'pci_acc_read_reg' [-Wmissing-prototypes]
   62 | u32 pci_acc_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_ohci.c:15:6: warning: no previous prototype for 'pci_ohci_write_reg' [-Wmissing-prototypes]
   15 | void pci_ohci_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_ohci.c:70:5: warning: no previous prototype for 'pci_ohci_read_reg' [-Wmissing-prototypes]
   70 | u32 pci_ohci_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_isa.c:84:6: warning: no previous prototype for 'pci_isa_write_bar' [-Wmissing-prototypes]
   84 | void pci_isa_write_bar(int n, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_isa.c:110:5: warning: no previous prototype for 'pci_isa_read_bar' [-Wmissing-prototypes]
  110 | u32 pci_isa_read_bar(int n)
arch/mips/loongson2ef/common/cs5536/cs5536_isa.c:134:6: warning: no previous prototype for 'pci_isa_write_reg' [-Wmissing-prototypes]
  134 | void pci_isa_write_reg(int reg, u32 value)
arch/mips/loongson2ef/common/cs5536/cs5536_isa.c:228:5: warning: no previous prototype for 'pci_isa_read_reg' [-Wmissing-prototypes]
  228 | u32 pci_isa_read_reg(int reg)

arch/mips/loongson2ef/common/cs5536/cs5536_mfgpt.c:195:12: warning: no previous prototype for 'init_mfgpt_clocksource' [-Wmissing-prototypes]
  195 | int __init init_mfgpt_clocksource(void)

Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Jiaxun Yang &lt;jiaxun.yang@flygoat.com&gt;
Cc: linux-mips@vger.kernel.org
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Signed-off-by: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'net-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next</title>
<updated>2025-05-28T22:24:36+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-05-28T22:24:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1b98f357dadd6ea613a435fbaef1a5dd7b35fd21'/>
<id>1b98f357dadd6ea613a435fbaef1a5dd7b35fd21</id>
<content type='text'>
Pull networking updates from Paolo Abeni:
 "Core:

   - Implement the Device Memory TCP transmit path, allowing zero-copy
     data transmission on top of TCP from e.g. GPU memory to the wire.

   - Move all the IPv6 routing tables management outside the RTNL scope,
     under its own lock and RCU. The route control path is now 3x times
     faster.

   - Convert queue related netlink ops to instance lock, reducing again
     the scope of the RTNL lock. This improves the control plane
     scalability.

   - Refactor the software crc32c implementation, removing unneeded
     abstraction layers and improving significantly the related
     micro-benchmarks.

   - Optimize the GRO engine for UDP-tunneled traffic, for a 10%
     performance improvement in related stream tests.

   - Cover more per-CPU storage with local nested BH locking; this is a
     prep work to remove the current per-CPU lock in local_bh_disable()
     on PREMPT_RT.

   - Introduce and use nlmsg_payload helper, combining buffer bounds
     verification with accessing payload carried by netlink messages.

  Netfilter:

   - Rewrite the procfs conntrack table implementation, improving
     considerably the dump performance. A lot of user-space tools still
     use this interface.

   - Implement support for wildcard netdevice in netdev basechain and
     flowtables.

   - Integrate conntrack information into nft trace infrastructure.

   - Export set count and backend name to userspace, for better
     introspection.

  BPF:

   - BPF qdisc support: BPF-qdisc can be implemented with BPF struct_ops
     programs and can be controlled in similar way to traditional qdiscs
     using the "tc qdisc" command.

   - Refactor the UDP socket iterator, addressing long standing issues
     WRT duplicate hits or missed sockets.

  Protocols:

   - Improve TCP receive buffer auto-tuning and increase the default
     upper bound for the receive buffer; overall this improves the
     single flow maximum thoughput on 200Gbs link by over 60%.

   - Add AFS GSSAPI security class to AF_RXRPC; it provides transport
     security for connections to the AFS fileserver and VL server.

   - Improve TCP multipath routing, so that the sources address always
     matches the nexthop device.

   - Introduce SO_PASSRIGHTS for AF_UNIX, to allow disabling SCM_RIGHTS,
     and thus preventing DoS caused by passing around problematic FDs.

   - Retire DCCP socket. DCCP only receives updates for bugs, and major
     distros disable it by default. Its removal allows for better
     organisation of TCP fields to reduce the number of cache lines hit
     in the fast path.

   - Extend TCP drop-reason support to cover PAWS checks.

  Driver API:

   - Reorganize PTP ioctl flag support to require an explicit opt-in for
     the drivers, avoiding the problem of drivers not rejecting new
     unsupported flags.

   - Converted several device drivers to timestamping APIs.

   - Introduce per-PHY ethtool dump helpers, improving the support for
     dump operations targeting PHYs.

  Tests and tooling:

   - Add support for classic netlink in user space C codegen, so that
     ynl-c can now read, create and modify links, routes addresses and
     qdisc layer configuration.

   - Add ynl sub-types for binary attributes, allowing ynl-c to output
     known struct instead of raw binary data, clarifying the classic
     netlink output.

   - Extend MPTCP selftests to improve the code-coverage.

   - Add tests for XDP tail adjustment in AF_XDP.

  New hardware / drivers:

   - OpenVPN virtual driver: offload OpenVPN data channels processing to
     the kernel-space, increasing the data transfer throughput WRT the
     user-space implementation.

   - Renesas glue driver for the gigabit ethernet RZ/V2H(P) SoC.

   - Broadcom asp-v3.0 ethernet driver.

   - AMD Renoir ethernet device.

   - ReakTek MT9888 2.5G ethernet PHY driver.

   - Aeonsemi 10G C45 PHYs driver.

  Drivers:

   - Ethernet high-speed NICs:
       - nVidia/Mellanox (mlx5):
           - refactor the steering table handling to significantly
             reduce the amount of memory used
           - add support for complex matches in H/W flow steering
           - improve flow streeing error handling
           - convert to netdev instance locking
       - Intel (100G, ice, igb, ixgbe, idpf):
           - ice: add switchdev support for LLDP traffic over VF
           - ixgbe: add firmware manipulation and regions devlink support
           - igb: introduce support for frame transmission premption
           - igb: adds persistent NAPI configuration
           - idpf: introduce RDMA support
           - idpf: add initial PTP support
       - Meta (fbnic):
           - extend hardware stats coverage
           - add devlink dev flash support
       - Broadcom (bnxt):
           - add support for RX-side device memory TCP
       - Wangxun (txgbe):
           - implement support for udp tunnel offload
           - complete PTP and SRIOV support for AML 25G/10G devices

   - Ethernet NICs embedded and virtual:
       - Google (gve):
           - add device memory TCP TX support
       - Amazon (ena):
           - support persistent per-NAPI config
       - Airoha:
           - add H/W support for L2 traffic offload
           - add per flow stats for flow offloading
       - RealTek (rtl8211): add support for WoL magic packet
       - Synopsys (stmmac):
           - dwmac-socfpga 1000BaseX support
           - add Loongson-2K3000 support
           - introduce support for hardware-accelerated VLAN stripping
       - Broadcom (bcmgenet):
           - expose more H/W stats
       - Freescale (enetc, dpaa2-eth):
           - enetc: add MAC filter, VLAN filter RSS and loopback support
           - dpaa2-eth: convert to H/W timestamping APIs
       - vxlan: convert FDB table to rhashtable, for better scalabilty
       - veth: apply qdisc backpressure on full ring to reduce TX drops

   - Ethernet switches:
       - Microchip (kzZ88x3): add ETS scheduler support

   - Ethernet PHYs:
       - RealTek (rtl8211):
           - add support for WoL magic packet
           - add support for PHY LEDs

   - CAN:
       - Adds RZ/G3E CANFD support to the rcar_canfd driver.
       - Preparatory work for CAN-XL support.
       - Add self-tests framework with support for CAN physical interfaces.

   - WiFi:
       - mac80211:
           - scan improvements with multi-link operation (MLO)
       - Qualcomm (ath12k):
           - enable AHB support for IPQ5332
           - add monitor interface support to QCN9274
           - add multi-link operation support to WCN7850
           - add 802.11d scan offload support to WCN7850
           - monitor mode for WCN7850, better 6 GHz regulatory
       - Qualcomm (ath11k):
           - restore hibernation support
       - MediaTek (mt76):
           - WiFi-7 improvements
           - implement support for mt7990
       - Intel (iwlwifi):
           - enhanced multi-link single-radio (EMLSR) support on 5 GHz links
           - rework device configuration
       - RealTek (rtw88):
           - improve throughput for RTL8814AU
       - RealTek (rtw89):
           - add multi-link operation support
           - STA/P2P concurrency improvements
           - support different SAR configs by antenna

   - Bluetooth:
       - introduce HCI Driver protocol
       - btintel_pcie: do not generate coredump for diagnostic events
       - btusb: add HCI Drv commands for configuring altsetting
       - btusb: add RTL8851BE device 0x0bda:0xb850
       - btusb: add new VID/PID 13d3/3584 for MT7922
       - btusb: add new VID/PID 13d3/3630 and 13d3/3613 for MT7925
       - btnxpuart: implement host-wakeup feature"

* tag 'net-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1611 commits)
  selftests/bpf: Fix bpf selftest build warning
  selftests: netfilter: Fix skip of wildcard interface test
  net: phy: mscc: Stop clearing the the UDPv4 checksum for L2 frames
  net: openvswitch: Fix the dead loop of MPLS parse
  calipso: Don't call calipso functions for AF_INET sk.
  selftests/tc-testing: Add a test for HFSC eltree double add with reentrant enqueue behaviour on netem
  net_sched: hfsc: Address reentrant enqueue adding class to eltree twice
  octeontx2-pf: QOS: Refactor TC_HTB_LEAF_DEL_LAST callback
  octeontx2-pf: QOS: Perform cache sync on send queue teardown
  net: mana: Add support for Multi Vports on Bare metal
  net: devmem: ncdevmem: remove unused variable
  net: devmem: ksft: upgrade rx test to send 1K data
  net: devmem: ksft: add 5 tuple FS support
  net: devmem: ksft: add exit_wait to make rx test pass
  net: devmem: ksft: add ipv4 support
  net: devmem: preserve sockc_err
  page_pool: fix ugly page_pool formatting
  net: devmem: move list_add to net_devmem_bind_dmabuf.
  selftests: netfilter: nft_queue.sh: include file transfer duration in log message
  net: phy: mscc: Fix memory leak when using one step timestamping
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking updates from Paolo Abeni:
 "Core:

   - Implement the Device Memory TCP transmit path, allowing zero-copy
     data transmission on top of TCP from e.g. GPU memory to the wire.

   - Move all the IPv6 routing tables management outside the RTNL scope,
     under its own lock and RCU. The route control path is now 3x times
     faster.

   - Convert queue related netlink ops to instance lock, reducing again
     the scope of the RTNL lock. This improves the control plane
     scalability.

   - Refactor the software crc32c implementation, removing unneeded
     abstraction layers and improving significantly the related
     micro-benchmarks.

   - Optimize the GRO engine for UDP-tunneled traffic, for a 10%
     performance improvement in related stream tests.

   - Cover more per-CPU storage with local nested BH locking; this is a
     prep work to remove the current per-CPU lock in local_bh_disable()
     on PREMPT_RT.

   - Introduce and use nlmsg_payload helper, combining buffer bounds
     verification with accessing payload carried by netlink messages.

  Netfilter:

   - Rewrite the procfs conntrack table implementation, improving
     considerably the dump performance. A lot of user-space tools still
     use this interface.

   - Implement support for wildcard netdevice in netdev basechain and
     flowtables.

   - Integrate conntrack information into nft trace infrastructure.

   - Export set count and backend name to userspace, for better
     introspection.

  BPF:

   - BPF qdisc support: BPF-qdisc can be implemented with BPF struct_ops
     programs and can be controlled in similar way to traditional qdiscs
     using the "tc qdisc" command.

   - Refactor the UDP socket iterator, addressing long standing issues
     WRT duplicate hits or missed sockets.

  Protocols:

   - Improve TCP receive buffer auto-tuning and increase the default
     upper bound for the receive buffer; overall this improves the
     single flow maximum thoughput on 200Gbs link by over 60%.

   - Add AFS GSSAPI security class to AF_RXRPC; it provides transport
     security for connections to the AFS fileserver and VL server.

   - Improve TCP multipath routing, so that the sources address always
     matches the nexthop device.

   - Introduce SO_PASSRIGHTS for AF_UNIX, to allow disabling SCM_RIGHTS,
     and thus preventing DoS caused by passing around problematic FDs.

   - Retire DCCP socket. DCCP only receives updates for bugs, and major
     distros disable it by default. Its removal allows for better
     organisation of TCP fields to reduce the number of cache lines hit
     in the fast path.

   - Extend TCP drop-reason support to cover PAWS checks.

  Driver API:

   - Reorganize PTP ioctl flag support to require an explicit opt-in for
     the drivers, avoiding the problem of drivers not rejecting new
     unsupported flags.

   - Converted several device drivers to timestamping APIs.

   - Introduce per-PHY ethtool dump helpers, improving the support for
     dump operations targeting PHYs.

  Tests and tooling:

   - Add support for classic netlink in user space C codegen, so that
     ynl-c can now read, create and modify links, routes addresses and
     qdisc layer configuration.

   - Add ynl sub-types for binary attributes, allowing ynl-c to output
     known struct instead of raw binary data, clarifying the classic
     netlink output.

   - Extend MPTCP selftests to improve the code-coverage.

   - Add tests for XDP tail adjustment in AF_XDP.

  New hardware / drivers:

   - OpenVPN virtual driver: offload OpenVPN data channels processing to
     the kernel-space, increasing the data transfer throughput WRT the
     user-space implementation.

   - Renesas glue driver for the gigabit ethernet RZ/V2H(P) SoC.

   - Broadcom asp-v3.0 ethernet driver.

   - AMD Renoir ethernet device.

   - ReakTek MT9888 2.5G ethernet PHY driver.

   - Aeonsemi 10G C45 PHYs driver.

  Drivers:

   - Ethernet high-speed NICs:
       - nVidia/Mellanox (mlx5):
           - refactor the steering table handling to significantly
             reduce the amount of memory used
           - add support for complex matches in H/W flow steering
           - improve flow streeing error handling
           - convert to netdev instance locking
       - Intel (100G, ice, igb, ixgbe, idpf):
           - ice: add switchdev support for LLDP traffic over VF
           - ixgbe: add firmware manipulation and regions devlink support
           - igb: introduce support for frame transmission premption
           - igb: adds persistent NAPI configuration
           - idpf: introduce RDMA support
           - idpf: add initial PTP support
       - Meta (fbnic):
           - extend hardware stats coverage
           - add devlink dev flash support
       - Broadcom (bnxt):
           - add support for RX-side device memory TCP
       - Wangxun (txgbe):
           - implement support for udp tunnel offload
           - complete PTP and SRIOV support for AML 25G/10G devices

   - Ethernet NICs embedded and virtual:
       - Google (gve):
           - add device memory TCP TX support
       - Amazon (ena):
           - support persistent per-NAPI config
       - Airoha:
           - add H/W support for L2 traffic offload
           - add per flow stats for flow offloading
       - RealTek (rtl8211): add support for WoL magic packet
       - Synopsys (stmmac):
           - dwmac-socfpga 1000BaseX support
           - add Loongson-2K3000 support
           - introduce support for hardware-accelerated VLAN stripping
       - Broadcom (bcmgenet):
           - expose more H/W stats
       - Freescale (enetc, dpaa2-eth):
           - enetc: add MAC filter, VLAN filter RSS and loopback support
           - dpaa2-eth: convert to H/W timestamping APIs
       - vxlan: convert FDB table to rhashtable, for better scalabilty
       - veth: apply qdisc backpressure on full ring to reduce TX drops

   - Ethernet switches:
       - Microchip (kzZ88x3): add ETS scheduler support

   - Ethernet PHYs:
       - RealTek (rtl8211):
           - add support for WoL magic packet
           - add support for PHY LEDs

   - CAN:
       - Adds RZ/G3E CANFD support to the rcar_canfd driver.
       - Preparatory work for CAN-XL support.
       - Add self-tests framework with support for CAN physical interfaces.

   - WiFi:
       - mac80211:
           - scan improvements with multi-link operation (MLO)
       - Qualcomm (ath12k):
           - enable AHB support for IPQ5332
           - add monitor interface support to QCN9274
           - add multi-link operation support to WCN7850
           - add 802.11d scan offload support to WCN7850
           - monitor mode for WCN7850, better 6 GHz regulatory
       - Qualcomm (ath11k):
           - restore hibernation support
       - MediaTek (mt76):
           - WiFi-7 improvements
           - implement support for mt7990
       - Intel (iwlwifi):
           - enhanced multi-link single-radio (EMLSR) support on 5 GHz links
           - rework device configuration
       - RealTek (rtw88):
           - improve throughput for RTL8814AU
       - RealTek (rtw89):
           - add multi-link operation support
           - STA/P2P concurrency improvements
           - support different SAR configs by antenna

   - Bluetooth:
       - introduce HCI Driver protocol
       - btintel_pcie: do not generate coredump for diagnostic events
       - btusb: add HCI Drv commands for configuring altsetting
       - btusb: add RTL8851BE device 0x0bda:0xb850
       - btusb: add new VID/PID 13d3/3584 for MT7922
       - btusb: add new VID/PID 13d3/3630 and 13d3/3613 for MT7925
       - btnxpuart: implement host-wakeup feature"

* tag 'net-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1611 commits)
  selftests/bpf: Fix bpf selftest build warning
  selftests: netfilter: Fix skip of wildcard interface test
  net: phy: mscc: Stop clearing the the UDPv4 checksum for L2 frames
  net: openvswitch: Fix the dead loop of MPLS parse
  calipso: Don't call calipso functions for AF_INET sk.
  selftests/tc-testing: Add a test for HFSC eltree double add with reentrant enqueue behaviour on netem
  net_sched: hfsc: Address reentrant enqueue adding class to eltree twice
  octeontx2-pf: QOS: Refactor TC_HTB_LEAF_DEL_LAST callback
  octeontx2-pf: QOS: Perform cache sync on send queue teardown
  net: mana: Add support for Multi Vports on Bare metal
  net: devmem: ncdevmem: remove unused variable
  net: devmem: ksft: upgrade rx test to send 1K data
  net: devmem: ksft: add 5 tuple FS support
  net: devmem: ksft: add exit_wait to make rx test pass
  net: devmem: ksft: add ipv4 support
  net: devmem: preserve sockc_err
  page_pool: fix ugly page_pool formatting
  net: devmem: move list_add to net_devmem_bind_dmabuf.
  selftests: netfilter: nft_queue.sh: include file transfer duration in log message
  net: phy: mscc: Fix memory leak when using one step timestamping
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'vfs-6.16-rc1.coredump' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs</title>
<updated>2025-05-26T18:17:01+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-05-26T18:17:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c5bfc48d5472fc60abafb510668d7bc3b5ecb401'/>
<id>c5bfc48d5472fc60abafb510668d7bc3b5ecb401</id>
<content type='text'>
Pull coredump updates from Christian Brauner:
 "This adds support for sending coredumps over an AF_UNIX socket. It
  also makes (implicit) use of the new SO_PEERPIDFD ability to hand out
  pidfds for reaped peer tasks

  The new coredump socket will allow userspace to not have to rely on
  usermode helpers for processing coredumps and provides a saf way to
  handle them instead of relying on super privileged coredumping helpers

  This will also be significantly more lightweight since the kernel
  doens't have to do a fork()+exec() for each crashing process to spawn
  a usermodehelper. Instead the kernel just connects to the AF_UNIX
  socket and userspace can process it concurrently however it sees fit.
  Support for userspace is incoming starting with systemd-coredump

  There's more work coming in that direction next cycle. The rest below
  goes into some details and background

  Coredumping currently supports two modes:

   (1) Dumping directly into a file somewhere on the filesystem.

   (2) Dumping into a pipe connected to a usermode helper process
       spawned as a child of the system_unbound_wq or kthreadd

  For simplicity I'm mostly ignoring (1). There's probably still some
  users of (1) out there but processing coredumps in this way can be
  considered adventurous especially in the face of set*id binaries

  The most common option should be (2) by now. It works by allowing
  userspace to put a string into /proc/sys/kernel/core_pattern like:

          |/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h

  The "|" at the beginning indicates to the kernel that a pipe must be
  used. The path following the pipe indicator is a path to a binary that
  will be spawned as a usermode helper process. Any additional
  parameters pass information about the task that is generating the
  coredump to the binary that processes the coredump

  In the example the core_pattern shown causes the kernel to spawn
  systemd-coredump as a usermode helper. There's various conceptual
  consequences of this (non-exhaustive list):

   - systemd-coredump is spawned with file descriptor number 0 (stdin)
     connected to the read-end of the pipe. All other file descriptors
     are closed. That specifically includes 1 (stdout) and 2 (stderr).

     This has already caused bugs because userspace assumed that this
     cannot happen (Whether or not this is a sane assumption is
     irrelevant)

   - systemd-coredump will be spawned as a child of system_unbound_wq.
     So it is not a child of any userspace process and specifically not
     a child of PID 1. It cannot be waited upon and is in a weird hybrid
     upcall which are difficult for userspace to control correctly

   - systemd-coredump is spawned with full kernel privileges. This
     necessitates all kinds of weird privilege dropping excercises in
     userspace to make this safe

   - A new usermode helper has to be spawned for each crashing process

  This adds a new mode:

   (3) Dumping into an AF_UNIX socket

  Userspace can set /proc/sys/kernel/core_pattern to:

          @/path/to/coredump.socket

  The "@" at the beginning indicates to the kernel that an AF_UNIX
  coredump socket will be used to process coredumps

  The coredump socket must be located in the initial mount namespace.
  When a task coredumps it opens a client socket in the initial network
  namespace and connects to the coredump socket:

   - The coredump server uses SO_PEERPIDFD to get a stable handle on the
     connected crashing task. The retrieved pidfd will provide a stable
     reference even if the crashing task gets SIGKILLed while generating
     the coredump. That is a huge attack vector right now

   - By setting core_pipe_limit non-zero userspace can guarantee that
     the crashing task cannot be reaped behind it's back and thus
     process all necessary information in /proc/&lt;pid&gt;. The SO_PEERPIDFD
     can be used to detect whether /proc/&lt;pid&gt; still refers to the same
     process

     The core_pipe_limit isn't used to rate-limit connections to the
     socket. This can simply be done via AF_UNIX socket directly

   - The pidfd for the crashing task will contain information how the
     task coredumps. The PIDFD_GET_INFO ioctl gained a new flag
     PIDFD_INFO_COREDUMP which can be used to retreive the coredump
     information

     If the coredump gets a new coredump client connection the kernel
     guarantees that PIDFD_INFO_COREDUMP information is available.

     Currently the following information is provided in the new
     @coredump_mask extension to struct pidfd_info:

      * PIDFD_COREDUMPED is raised if the task did actually coredump

      * PIDFD_COREDUMP_SKIP is raised if the task skipped coredumping
        (e.g., undumpable)

      * PIDFD_COREDUMP_USER is raised if this is a regular coredump and
        doesn't need special care by the coredump server

      * PIDFD_COREDUMP_ROOT is raised if the generated coredump should
        be treated as sensitive and the coredump server should restrict
        access to the generated coredump to sufficiently privileged
        users"

* tag 'vfs-6.16-rc1.coredump' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  mips, net: ensure that SOCK_COREDUMP is defined
  selftests/coredump: add tests for AF_UNIX coredumps
  selftests/pidfd: add PIDFD_INFO_COREDUMP infrastructure
  coredump: validate socket name as it is written
  coredump: show supported coredump modes
  pidfs, coredump: add PIDFD_INFO_COREDUMP
  coredump: add coredump socket
  coredump: reflow dump helpers a little
  coredump: massage do_coredump()
  coredump: massage format_corename()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull coredump updates from Christian Brauner:
 "This adds support for sending coredumps over an AF_UNIX socket. It
  also makes (implicit) use of the new SO_PEERPIDFD ability to hand out
  pidfds for reaped peer tasks

  The new coredump socket will allow userspace to not have to rely on
  usermode helpers for processing coredumps and provides a saf way to
  handle them instead of relying on super privileged coredumping helpers

  This will also be significantly more lightweight since the kernel
  doens't have to do a fork()+exec() for each crashing process to spawn
  a usermodehelper. Instead the kernel just connects to the AF_UNIX
  socket and userspace can process it concurrently however it sees fit.
  Support for userspace is incoming starting with systemd-coredump

  There's more work coming in that direction next cycle. The rest below
  goes into some details and background

  Coredumping currently supports two modes:

   (1) Dumping directly into a file somewhere on the filesystem.

   (2) Dumping into a pipe connected to a usermode helper process
       spawned as a child of the system_unbound_wq or kthreadd

  For simplicity I'm mostly ignoring (1). There's probably still some
  users of (1) out there but processing coredumps in this way can be
  considered adventurous especially in the face of set*id binaries

  The most common option should be (2) by now. It works by allowing
  userspace to put a string into /proc/sys/kernel/core_pattern like:

          |/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h

  The "|" at the beginning indicates to the kernel that a pipe must be
  used. The path following the pipe indicator is a path to a binary that
  will be spawned as a usermode helper process. Any additional
  parameters pass information about the task that is generating the
  coredump to the binary that processes the coredump

  In the example the core_pattern shown causes the kernel to spawn
  systemd-coredump as a usermode helper. There's various conceptual
  consequences of this (non-exhaustive list):

   - systemd-coredump is spawned with file descriptor number 0 (stdin)
     connected to the read-end of the pipe. All other file descriptors
     are closed. That specifically includes 1 (stdout) and 2 (stderr).

     This has already caused bugs because userspace assumed that this
     cannot happen (Whether or not this is a sane assumption is
     irrelevant)

   - systemd-coredump will be spawned as a child of system_unbound_wq.
     So it is not a child of any userspace process and specifically not
     a child of PID 1. It cannot be waited upon and is in a weird hybrid
     upcall which are difficult for userspace to control correctly

   - systemd-coredump is spawned with full kernel privileges. This
     necessitates all kinds of weird privilege dropping excercises in
     userspace to make this safe

   - A new usermode helper has to be spawned for each crashing process

  This adds a new mode:

   (3) Dumping into an AF_UNIX socket

  Userspace can set /proc/sys/kernel/core_pattern to:

          @/path/to/coredump.socket

  The "@" at the beginning indicates to the kernel that an AF_UNIX
  coredump socket will be used to process coredumps

  The coredump socket must be located in the initial mount namespace.
  When a task coredumps it opens a client socket in the initial network
  namespace and connects to the coredump socket:

   - The coredump server uses SO_PEERPIDFD to get a stable handle on the
     connected crashing task. The retrieved pidfd will provide a stable
     reference even if the crashing task gets SIGKILLed while generating
     the coredump. That is a huge attack vector right now

   - By setting core_pipe_limit non-zero userspace can guarantee that
     the crashing task cannot be reaped behind it's back and thus
     process all necessary information in /proc/&lt;pid&gt;. The SO_PEERPIDFD
     can be used to detect whether /proc/&lt;pid&gt; still refers to the same
     process

     The core_pipe_limit isn't used to rate-limit connections to the
     socket. This can simply be done via AF_UNIX socket directly

   - The pidfd for the crashing task will contain information how the
     task coredumps. The PIDFD_GET_INFO ioctl gained a new flag
     PIDFD_INFO_COREDUMP which can be used to retreive the coredump
     information

     If the coredump gets a new coredump client connection the kernel
     guarantees that PIDFD_INFO_COREDUMP information is available.

     Currently the following information is provided in the new
     @coredump_mask extension to struct pidfd_info:

      * PIDFD_COREDUMPED is raised if the task did actually coredump

      * PIDFD_COREDUMP_SKIP is raised if the task skipped coredumping
        (e.g., undumpable)

      * PIDFD_COREDUMP_USER is raised if this is a regular coredump and
        doesn't need special care by the coredump server

      * PIDFD_COREDUMP_ROOT is raised if the generated coredump should
        be treated as sensitive and the coredump server should restrict
        access to the generated coredump to sufficiently privileged
        users"

* tag 'vfs-6.16-rc1.coredump' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  mips, net: ensure that SOCK_COREDUMP is defined
  selftests/coredump: add tests for AF_UNIX coredumps
  selftests/pidfd: add PIDFD_INFO_COREDUMP infrastructure
  coredump: validate socket name as it is written
  coredump: show supported coredump modes
  pidfs, coredump: add PIDFD_INFO_COREDUMP
  coredump: add coredump socket
  coredump: reflow dump helpers a little
  coredump: massage do_coredump()
  coredump: massage format_corename()
</pre>
</div>
</content>
</entry>
<entry>
<title>af_unix: Introduce SO_PASSRIGHTS.</title>
<updated>2025-05-23T09:24:18+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2025-05-19T20:57:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=77cbe1a6d8730a07f99f9263c2d5f2304cf5e830'/>
<id>77cbe1a6d8730a07f99f9263c2d5f2304cf5e830</id>
<content type='text'>
As long as recvmsg() or recvmmsg() is used with cmsg, it is not
possible to avoid receiving file descriptors via SCM_RIGHTS.

This behaviour has occasionally been flagged as problematic, as
it can be (ab)used to trigger DoS during close(), for example, by
passing a FUSE-controlled fd or a hung NFS fd.

For instance, as noted on the uAPI Group page [0], an untrusted peer
could send a file descriptor pointing to a hung NFS mount and then
close it.  Once the receiver calls recvmsg() with msg_control, the
descriptor is automatically installed, and then the responsibility
for the final close() now falls on the receiver, which may result
in blocking the process for a long time.

Regarding this, systemd calls cmsg_close_all() [1] after each
recvmsg() to close() unwanted file descriptors sent via SCM_RIGHTS.

However, this cannot work around the issue at all, because the final
fput() may still occur on the receiver's side once sendmsg() with
SCM_RIGHTS succeeds.  Also, even filtering by LSM at recvmsg() does
not work for the same reason.

Thus, we need a better way to refuse SCM_RIGHTS at sendmsg().

Let's introduce SO_PASSRIGHTS to disable SCM_RIGHTS.

Note that this option is enabled by default for backward
compatibility.

Link: https://uapi-group.org/kernel-features/#disabling-reception-of-scm_rights-for-af_unix-sockets #[0]
Link: https://github.com/systemd/systemd/blob/v257.5/src/basic/fd-util.c#L612-L628 #[1]
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As long as recvmsg() or recvmmsg() is used with cmsg, it is not
possible to avoid receiving file descriptors via SCM_RIGHTS.

This behaviour has occasionally been flagged as problematic, as
it can be (ab)used to trigger DoS during close(), for example, by
passing a FUSE-controlled fd or a hung NFS fd.

For instance, as noted on the uAPI Group page [0], an untrusted peer
could send a file descriptor pointing to a hung NFS mount and then
close it.  Once the receiver calls recvmsg() with msg_control, the
descriptor is automatically installed, and then the responsibility
for the final close() now falls on the receiver, which may result
in blocking the process for a long time.

Regarding this, systemd calls cmsg_close_all() [1] after each
recvmsg() to close() unwanted file descriptors sent via SCM_RIGHTS.

However, this cannot work around the issue at all, because the final
fput() may still occur on the receiver's side once sendmsg() with
SCM_RIGHTS succeeds.  Also, even filtering by LSM at recvmsg() does
not work for the same reason.

Thus, we need a better way to refuse SCM_RIGHTS at sendmsg().

Let's introduce SO_PASSRIGHTS to disable SCM_RIGHTS.

Note that this option is enabled by default for backward
compatibility.

Link: https://uapi-group.org/kernel-features/#disabling-reception-of-scm_rights-for-af_unix-sockets #[0]
Link: https://github.com/systemd/systemd/blob/v257.5/src/basic/fd-util.c#L612-L628 #[1]
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mips, net: ensure that SOCK_COREDUMP is defined</title>
<updated>2025-05-23T09:02:16+00:00</updated>
<author>
<name>Christian Brauner</name>
<email>brauner@kernel.org</email>
</author>
<published>2025-05-23T08:47:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4e83ae6ec87dddac070ba349d3b839589b1bb957'/>
<id>4e83ae6ec87dddac070ba349d3b839589b1bb957</id>
<content type='text'>
For historical reasons mips has to override the socket enum values but
the defines are all the same. So simply move the ARCH_HAS_SOCKET_TYPES
scope.

Fixes: a9194f88782a ("coredump: add coredump socket")
Suggested-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For historical reasons mips has to override the socket enum values but
the defines are all the same. So simply move the ARCH_HAS_SOCKET_TYPES
scope.

Fixes: a9194f88782a ("coredump: add coredump socket")
Suggested-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: pass mm down to pagetable_{pte,pmd}_ctor</title>
<updated>2025-05-12T00:48:21+00:00</updated>
<author>
<name>Kevin Brodsky</name>
<email>kevin.brodsky@arm.com</email>
</author>
<published>2025-04-08T09:52:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d82d3bf4115217bb3f43f9320bad5d68a35c278f'/>
<id>d82d3bf4115217bb3f43f9320bad5d68a35c278f</id>
<content type='text'>
Patch series "Always call constructor for kernel page tables", v2.

There has been much confusion around exactly when page table
constructors/destructors (pagetable_*_[cd]tor) are supposed to be called. 
They were initially introduced for user PTEs only (to support split page
table locks), then at the PMD level for the same purpose.  Accounting was
added later on, starting at the PTE level and then moving to higher levels
(PMD, PUD).  Finally, with my earlier series "Account page tables at all
levels" [1], the ctor/dtor is run for all levels, all the way to PGD.

I thought this was the end of the story, and it hopefully is for user
pgtables, but I was wrong for what concerns kernel pgtables.  The current
situation there makes very little sense:

* At the PTE level, the ctor/dtor is not called (at least in the generic
  implementation).  Specific helpers are used for kernel pgtables at this
  level (pte_{alloc,free}_kernel()) and those have never called the
  ctor/dtor, most likely because they were initially irrelevant in the
  kernel case.

* At all other levels, the ctor/dtor is normally called.  This is
  potentially wasteful at the PMD level (more on that later).

This series aims to ensure that the ctor/dtor is always called for kernel
pgtables, as it already is for user pgtables.  Besides consistency, the
main motivation is to guarantee that ctor/dtor hooks are systematically
called; this makes it possible to insert hooks to protect page tables [2],
for instance.  There is however an extra challenge: split locks are not
used for kernel pgtables, and it would therefore be wasteful to initialise
them (ptlock_init()).

It is worth clarifying exactly when split locks are used.  They clearly
are for user pgtables, but as illustrated in commit 61444cde9170 ("ARM:
8591/1: mm: use fully constructed struct pages for EFI pgd allocations"),
they also are for special page tables like efi_mm.  The one case where
split locks are definitely unused is pgtables owned by init_mm; this is
consistent with the behaviour of apply_to_pte_range().

The approach chosen in this series is therefore to pass the mm associated
to the pgtables being constructed to pagetable_{pte,pmd}_ctor() (patch 1),
and skip ptlock_init() if mm == &amp;init_mm (patch 3 and 7).  This makes it
possible to call the PTE ctor/dtor from pte_{alloc,free}_kernel() without
unintended consequences (patch 3).  As a result the accounting functions
are now called at all levels for kernel pgtables, and split locks are
never initialised.

In configurations where ptlocks are dynamically allocated (32-bit,
PREEMPT_RT, etc.) and ARCH_ENABLE_SPLIT_PMD_PTLOCK is selected, this
series results in the removal of a kmem_cache allocation for every kernel
PMD.  Additionally, for certain architectures that do not use
&lt;asm-generic/pgalloc.h&gt; such as s390, the same optimisation occurs at the
PTE level.

===

Things get more complicated when it comes to special pgtable allocators
(patch 8-12).  All architectures need such allocators to create initial
kernel pgtables; we are not concerned with those as the ctor cannot be
called so early in the boot sequence.  However, those allocators may also
be used later in the boot sequence or during normal operations.  There are
two main use-cases:

1. Mapping EFI memory: efi_mm (arm, arm64, riscv)
2. arch_add_memory(): init_mm

The ctor is already explicitly run (at the PTE/PMD level) in the first
case, as required for pgtables that are not associated with init_mm. 
However the same allocators may also be used for the second use-case (or
others), and this is where it gets messy.  Patch 1 calls the ctor with
NULL as mm in those situations, as the actual mm isn't available. 
Practically this means that ptlocks will be unconditionally initialised. 
This is fine on arm - create_mapping_late() is only used for the EFI
mapping.  On arm64, __create_pgd_mapping() is also used by
arch_add_memory(); patch 8/9/11 ensure that ctors are called at all levels
with the appropriate mm.  The situation is similar on riscv, but
propagating the mm down to the ctor would require significant refactoring.
Since they are already called unconditionally, this series leaves riscv
no worse off - patch 10 adds comments to clarify the situation.

From a cursory look at other architectures implementing arch_add_memory(),
s390 and x86 may also need a similar treatment to add constructor calls. 
This is to be taken care of in a future version or as a follow-up.

===

The complications in those special pgtable allocators beg the question:
does it really make sense to treat efi_mm and init_mm differently in e.g. 
apply_to_pte_range()?  Maybe what we really need is a way to tell if an mm
corresponds to user memory or not, and never use split locks for non-user
mm's.  Feedback and suggestions welcome!


This patch (of 12):

In preparation for calling constructors for all kernel page tables while
eliding unnecessary ptlock initialisation, let's pass down the associated
mm to the PTE/PMD level ctors.  (These are the two levels where ptlocks
are used.)

In most cases the mm is already around at the point of calling the ctor so
we simply pass it down.  This is however not the case for special page
table allocators:

* arch/arm/mm/mmu.c
* arch/arm64/mm/mmu.c
* arch/riscv/mm/init.c

In those cases, the page tables being allocated are either for standard
kernel memory (init_mm) or special page directories, which may not be
associated to any mm.  For now let's pass NULL as mm; this will be refined
where possible in future patches.

No functional change in this patch.

Link: https://lore.kernel.org/linux-mm/20250103184415.2744423-1-kevin.brodsky@arm.com/ [1]
Link: https://lore.kernel.org/linux-hardening/20250203101839.1223008-1-kevin.brodsky@arm.com/ [2]
Link: https://lkml.kernel.org/r/20250408095222.860601-1-kevin.brodsky@arm.com
Link: https://lkml.kernel.org/r/20250408095222.860601-2-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky &lt;kevin.brodsky@arm.com&gt;
Reviewed-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;	[s390]
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Andreas Larsson &lt;andreas@gaisler.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Kevin Brodsky &lt;kevin.brodsky@arm.com&gt;
Cc: Linus Waleij &lt;linus.walleij@linaro.org&gt;
Cc: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Qi Zheng &lt;zhengqi.arch@bytedance.com&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Yang Shi &lt;yang@os.amperecomputing.com&gt;
Cc: &lt;x86@kernel.org&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Patch series "Always call constructor for kernel page tables", v2.

There has been much confusion around exactly when page table
constructors/destructors (pagetable_*_[cd]tor) are supposed to be called. 
They were initially introduced for user PTEs only (to support split page
table locks), then at the PMD level for the same purpose.  Accounting was
added later on, starting at the PTE level and then moving to higher levels
(PMD, PUD).  Finally, with my earlier series "Account page tables at all
levels" [1], the ctor/dtor is run for all levels, all the way to PGD.

I thought this was the end of the story, and it hopefully is for user
pgtables, but I was wrong for what concerns kernel pgtables.  The current
situation there makes very little sense:

* At the PTE level, the ctor/dtor is not called (at least in the generic
  implementation).  Specific helpers are used for kernel pgtables at this
  level (pte_{alloc,free}_kernel()) and those have never called the
  ctor/dtor, most likely because they were initially irrelevant in the
  kernel case.

* At all other levels, the ctor/dtor is normally called.  This is
  potentially wasteful at the PMD level (more on that later).

This series aims to ensure that the ctor/dtor is always called for kernel
pgtables, as it already is for user pgtables.  Besides consistency, the
main motivation is to guarantee that ctor/dtor hooks are systematically
called; this makes it possible to insert hooks to protect page tables [2],
for instance.  There is however an extra challenge: split locks are not
used for kernel pgtables, and it would therefore be wasteful to initialise
them (ptlock_init()).

It is worth clarifying exactly when split locks are used.  They clearly
are for user pgtables, but as illustrated in commit 61444cde9170 ("ARM:
8591/1: mm: use fully constructed struct pages for EFI pgd allocations"),
they also are for special page tables like efi_mm.  The one case where
split locks are definitely unused is pgtables owned by init_mm; this is
consistent with the behaviour of apply_to_pte_range().

The approach chosen in this series is therefore to pass the mm associated
to the pgtables being constructed to pagetable_{pte,pmd}_ctor() (patch 1),
and skip ptlock_init() if mm == &amp;init_mm (patch 3 and 7).  This makes it
possible to call the PTE ctor/dtor from pte_{alloc,free}_kernel() without
unintended consequences (patch 3).  As a result the accounting functions
are now called at all levels for kernel pgtables, and split locks are
never initialised.

In configurations where ptlocks are dynamically allocated (32-bit,
PREEMPT_RT, etc.) and ARCH_ENABLE_SPLIT_PMD_PTLOCK is selected, this
series results in the removal of a kmem_cache allocation for every kernel
PMD.  Additionally, for certain architectures that do not use
&lt;asm-generic/pgalloc.h&gt; such as s390, the same optimisation occurs at the
PTE level.

===

Things get more complicated when it comes to special pgtable allocators
(patch 8-12).  All architectures need such allocators to create initial
kernel pgtables; we are not concerned with those as the ctor cannot be
called so early in the boot sequence.  However, those allocators may also
be used later in the boot sequence or during normal operations.  There are
two main use-cases:

1. Mapping EFI memory: efi_mm (arm, arm64, riscv)
2. arch_add_memory(): init_mm

The ctor is already explicitly run (at the PTE/PMD level) in the first
case, as required for pgtables that are not associated with init_mm. 
However the same allocators may also be used for the second use-case (or
others), and this is where it gets messy.  Patch 1 calls the ctor with
NULL as mm in those situations, as the actual mm isn't available. 
Practically this means that ptlocks will be unconditionally initialised. 
This is fine on arm - create_mapping_late() is only used for the EFI
mapping.  On arm64, __create_pgd_mapping() is also used by
arch_add_memory(); patch 8/9/11 ensure that ctors are called at all levels
with the appropriate mm.  The situation is similar on riscv, but
propagating the mm down to the ctor would require significant refactoring.
Since they are already called unconditionally, this series leaves riscv
no worse off - patch 10 adds comments to clarify the situation.

From a cursory look at other architectures implementing arch_add_memory(),
s390 and x86 may also need a similar treatment to add constructor calls. 
This is to be taken care of in a future version or as a follow-up.

===

The complications in those special pgtable allocators beg the question:
does it really make sense to treat efi_mm and init_mm differently in e.g. 
apply_to_pte_range()?  Maybe what we really need is a way to tell if an mm
corresponds to user memory or not, and never use split locks for non-user
mm's.  Feedback and suggestions welcome!


This patch (of 12):

In preparation for calling constructors for all kernel page tables while
eliding unnecessary ptlock initialisation, let's pass down the associated
mm to the PTE/PMD level ctors.  (These are the two levels where ptlocks
are used.)

In most cases the mm is already around at the point of calling the ctor so
we simply pass it down.  This is however not the case for special page
table allocators:

* arch/arm/mm/mmu.c
* arch/arm64/mm/mmu.c
* arch/riscv/mm/init.c

In those cases, the page tables being allocated are either for standard
kernel memory (init_mm) or special page directories, which may not be
associated to any mm.  For now let's pass NULL as mm; this will be refined
where possible in future patches.

No functional change in this patch.

Link: https://lore.kernel.org/linux-mm/20250103184415.2744423-1-kevin.brodsky@arm.com/ [1]
Link: https://lore.kernel.org/linux-hardening/20250203101839.1223008-1-kevin.brodsky@arm.com/ [2]
Link: https://lkml.kernel.org/r/20250408095222.860601-1-kevin.brodsky@arm.com
Link: https://lkml.kernel.org/r/20250408095222.860601-2-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky &lt;kevin.brodsky@arm.com&gt;
Reviewed-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;	[s390]
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Andreas Larsson &lt;andreas@gaisler.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Kevin Brodsky &lt;kevin.brodsky@arm.com&gt;
Cc: Linus Waleij &lt;linus.walleij@linaro.org&gt;
Cc: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Qi Zheng &lt;zhengqi.arch@bytedance.com&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Yang Shi &lt;yang@os.amperecomputing.com&gt;
Cc: &lt;x86@kernel.org&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
