<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/mm/page_alloc.c, branch v7.1-rc4</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'slab-for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab</title>
<updated>2026-05-03T15:19:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-05-03T15:19:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=811129272de4f91da34f869ae1a1dd1fe608f64f'/>
<id>811129272de4f91da34f869ae1a1dd1fe608f64f</id>
<content type='text'>
Pull slab fixes from Vlastimil Babka:

 - Stable fixes for CONFIG_SMP=n where _nolock() allocations in NMI both
   at kmalloc and page allocator levels are not properly protected by
   the spin_trylock() semantics on !SMP (Harry Yoo)

* tag 'slab-for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
  mm/slab: return NULL early from kmalloc_nolock() in NMI on UP
  mm/page_alloc: return NULL early from alloc_frozen_pages_nolock() in NMI on UP
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull slab fixes from Vlastimil Babka:

 - Stable fixes for CONFIG_SMP=n where _nolock() allocations in NMI both
   at kmalloc and page allocator levels are not properly protected by
   the spin_trylock() semantics on !SMP (Harry Yoo)

* tag 'slab-for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
  mm/slab: return NULL early from kmalloc_nolock() in NMI on UP
  mm/page_alloc: return NULL early from alloc_frozen_pages_nolock() in NMI on UP
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/page_alloc: return NULL early from alloc_frozen_pages_nolock() in NMI on UP</title>
<updated>2026-04-27T07:14:36+00:00</updated>
<author>
<name>Harry Yoo (Oracle)</name>
<email>harry@kernel.org</email>
</author>
<published>2026-04-27T07:09:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=620b46ed6ae17c8438d889c8c0cfddab36a1476c'/>
<id>620b46ed6ae17c8438d889c8c0cfddab36a1476c</id>
<content type='text'>
On UP kernels (!CONFIG_SMP), spin_trylock() is a no-op that
unconditionally succeeds even when the lock is already held. As a
result, alloc_frozen_pages_nolock() called from NMI context can
re-enter rmqueue() and acquire the zone lock that the interrupted
context is already holding, corrupting the freelists.

With CONFIG_DEBUG_SPINLOCK on UP, the following BUG is triggered with
the slub_kunit test module:

  BUG: spinlock trylock failure on UP on CPU#0, kunit_try_catch/243
  [...]
  Call Trace:
   &lt;NMI&gt;
   dump_stack_lvl+0x3f/0x60
   do_raw_spin_trylock+0x41/0x50
   _raw_spin_trylock+0x24/0x50
   rmqueue.isra.0+0x2a9/0xa70
   get_page_from_freelist+0xeb/0x450
   alloc_frozen_pages_nolock_noprof+0x111/0x1e0
   allocate_slab+0x42a/0x500
   ___slab_alloc+0xa7/0x4c0
   kmalloc_nolock_noprof+0x164/0x310
   [...]
   &lt;/NMI&gt;

Fix this by returning NULL early when invoked from NMI on a UP kernel.

Link: https://lore.kernel.org/linux-mm/ad_cqe51pvr1WaDg@hyeyoo
Cc: stable@vger.kernel.org
Fixes: d7242af86434 ("mm: Introduce alloc_frozen_pages_nolock()")
Signed-off-by: Harry Yoo (Oracle) &lt;harry@kernel.org&gt;
Link: https://patch.msgid.link/20260427-nolock-api-fix-v2-1-a6b83a92d9a4@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) &lt;vbabka@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
On UP kernels (!CONFIG_SMP), spin_trylock() is a no-op that
unconditionally succeeds even when the lock is already held. As a
result, alloc_frozen_pages_nolock() called from NMI context can
re-enter rmqueue() and acquire the zone lock that the interrupted
context is already holding, corrupting the freelists.

With CONFIG_DEBUG_SPINLOCK on UP, the following BUG is triggered with
the slub_kunit test module:

  BUG: spinlock trylock failure on UP on CPU#0, kunit_try_catch/243
  [...]
  Call Trace:
   &lt;NMI&gt;
   dump_stack_lvl+0x3f/0x60
   do_raw_spin_trylock+0x41/0x50
   _raw_spin_trylock+0x24/0x50
   rmqueue.isra.0+0x2a9/0xa70
   get_page_from_freelist+0xeb/0x450
   alloc_frozen_pages_nolock_noprof+0x111/0x1e0
   allocate_slab+0x42a/0x500
   ___slab_alloc+0xa7/0x4c0
   kmalloc_nolock_noprof+0x164/0x310
   [...]
   &lt;/NMI&gt;

Fix this by returning NULL early when invoked from NMI on a UP kernel.

Link: https://lore.kernel.org/linux-mm/ad_cqe51pvr1WaDg@hyeyoo
Cc: stable@vger.kernel.org
Fixes: d7242af86434 ("mm: Introduce alloc_frozen_pages_nolock()")
Signed-off-by: Harry Yoo (Oracle) &lt;harry@kernel.org&gt;
Link: https://patch.msgid.link/20260427-nolock-api-fix-v2-1-a6b83a92d9a4@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) &lt;vbabka@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2026-04-18-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2026-04-19T15:01:17+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-04-19T15:01:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=40735a683bf844a453d7a0f91e5e3daa0abc659b'/>
<id>40735a683bf844a453d7a0f91e5e3daa0abc659b</id>
<content type='text'>
Pull more MM updates from Andrew Morton:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

 - "mm/damon/core: validate damos_quota_goal-&gt;nid" (SeongJae Park)

   Fix a couple of root-only wild pointer dereferences

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

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

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

   Bugfixes and a cleanup for the HMM kernel selftests

 - "Modify memfd_luo code" (Chenghao Duan)

   Cleanups, simplifications and speedups to the memfd_lou code

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

   Support for userfaultfd in guest_memfd

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

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

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

   A couple of nice speedups for mprotect()

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

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

* tag 'mm-stable-2026-04-18-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (121 commits)
  MAINTAINERS: add page cache reviewer
  mm/vmscan: avoid false-positive -Wuninitialized warning
  MAINTAINERS: update Dave's kdump reviewer email address
  MAINTAINERS: drop include/linux/liveupdate from LIVE UPDATE
  MAINTAINERS: drop include/linux/kho/abi/ from KHO
  MAINTAINERS: update KHO and LIVE UPDATE maintainers
  MAINTAINERS: update kexec/kdump maintainers entries
  mm/migrate_device: remove dead migration entry check in migrate_vma_collect_huge_pmd()
  selftests: mm: skip charge_reserved_hugetlb without killall
  userfaultfd: allow registration of ranges below mmap_min_addr
  mm/vmstat: fix vmstat_shepherd double-scheduling vmstat_update
  mm/hugetlb: fix early boot crash on parameters without '=' separator
  zram: reject unrecognized type= values in recompress_store()
  docs: proc: document ProtectionKey in smaps
  mm/mprotect: special-case small folios when applying permissions
  mm/mprotect: move softleaf code out of the main function
  mm: remove '!root_reclaim' checking in should_abort_scan()
  mm/sparse: fix comment for section map alignment
  mm/page_io: use sio-&gt;len for PSWPIN accounting in sio_read_complete()
  selftests/mm: transhuge_stress: skip the test when thp not available
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull more MM updates from Andrew Morton:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

 - "mm/damon/core: validate damos_quota_goal-&gt;nid" (SeongJae Park)

   Fix a couple of root-only wild pointer dereferences

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

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

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

   Bugfixes and a cleanup for the HMM kernel selftests

 - "Modify memfd_luo code" (Chenghao Duan)

   Cleanups, simplifications and speedups to the memfd_lou code

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

   Support for userfaultfd in guest_memfd

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

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

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

   A couple of nice speedups for mprotect()

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

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

* tag 'mm-stable-2026-04-18-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (121 commits)
  MAINTAINERS: add page cache reviewer
  mm/vmscan: avoid false-positive -Wuninitialized warning
  MAINTAINERS: update Dave's kdump reviewer email address
  MAINTAINERS: drop include/linux/liveupdate from LIVE UPDATE
  MAINTAINERS: drop include/linux/kho/abi/ from KHO
  MAINTAINERS: update KHO and LIVE UPDATE maintainers
  MAINTAINERS: update kexec/kdump maintainers entries
  mm/migrate_device: remove dead migration entry check in migrate_vma_collect_huge_pmd()
  selftests: mm: skip charge_reserved_hugetlb without killall
  userfaultfd: allow registration of ranges below mmap_min_addr
  mm/vmstat: fix vmstat_shepherd double-scheduling vmstat_update
  mm/hugetlb: fix early boot crash on parameters without '=' separator
  zram: reject unrecognized type= values in recompress_store()
  docs: proc: document ProtectionKey in smaps
  mm/mprotect: special-case small folios when applying permissions
  mm/mprotect: move softleaf code out of the main function
  mm: remove '!root_reclaim' checking in should_abort_scan()
  mm/sparse: fix comment for section map alignment
  mm/page_io: use sio-&gt;len for PSWPIN accounting in sio_read_complete()
  selftests/mm: transhuge_stress: skip the test when thp not available
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'memblock-v7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock</title>
<updated>2026-04-18T18:29:14+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-04-18T18:29:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9055c64567e9fc2a58d9382205bf3082f7bea141'/>
<id>9055c64567e9fc2a58d9382205bf3082f7bea141</id>
<content type='text'>
Pull memblock updates from Mike Rapoport:

 - improve debuggability of reserve_mem kernel parameter handling with
   print outs in case of a failure and debugfs info showing what was
   actually reserved

 - Make memblock_free_late() and free_reserved_area() use the same core
   logic for freeing the memory to buddy and ensure it takes care of
   updating memblock arrays when ARCH_KEEP_MEMBLOCK is enabled.

* tag 'memblock-v7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
  x86/alternative: delay freeing of smp_locks section
  memblock: warn when freeing reserved memory before memory map is initialized
  memblock, treewide: make memblock_free() handle late freeing
  memblock: make free_reserved_area() update memblock if ARCH_KEEP_MEMBLOCK=y
  memblock: extract page freeing from free_reserved_area() into a helper
  memblock: make free_reserved_area() more robust
  mm: move free_reserved_area() to mm/memblock.c
  powerpc: opal-core: pair alloc_pages_exact() with free_pages_exact()
  powerpc: fadump: pair alloc_pages_exact() with free_pages_exact()
  memblock: reserve_mem: fix end caclulation in reserve_mem_release_by_name()
  memblock: move reserve_bootmem_range() to memblock.c and make it static
  memblock: Add reserve_mem debugfs info
  memblock: Print out errors on reserve_mem parser
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull memblock updates from Mike Rapoport:

 - improve debuggability of reserve_mem kernel parameter handling with
   print outs in case of a failure and debugfs info showing what was
   actually reserved

 - Make memblock_free_late() and free_reserved_area() use the same core
   logic for freeing the memory to buddy and ensure it takes care of
   updating memblock arrays when ARCH_KEEP_MEMBLOCK is enabled.

* tag 'memblock-v7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
  x86/alternative: delay freeing of smp_locks section
  memblock: warn when freeing reserved memory before memory map is initialized
  memblock, treewide: make memblock_free() handle late freeing
  memblock: make free_reserved_area() update memblock if ARCH_KEEP_MEMBLOCK=y
  memblock: extract page freeing from free_reserved_area() into a helper
  memblock: make free_reserved_area() more robust
  mm: move free_reserved_area() to mm/memblock.c
  powerpc: opal-core: pair alloc_pages_exact() with free_pages_exact()
  powerpc: fadump: pair alloc_pages_exact() with free_pages_exact()
  memblock: reserve_mem: fix end caclulation in reserve_mem_release_by_name()
  memblock: move reserve_bootmem_range() to memblock.c and make it static
  memblock: Add reserve_mem debugfs info
  memblock: Print out errors on reserve_mem parser
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/alloc_tag: clear codetag for pages allocated before page_ext initialization</title>
<updated>2026-04-18T07:10:50+00:00</updated>
<author>
<name>Hao Ge</name>
<email>hao.ge@linux.dev</email>
</author>
<published>2026-03-31T08:13:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6b1842775a460245e97d36d3a67d0cfba7c4ff79'/>
<id>6b1842775a460245e97d36d3a67d0cfba7c4ff79</id>
<content type='text'>
Due to initialization ordering, page_ext is allocated and initialized
relatively late during boot.  Some pages have already been allocated and
freed before page_ext becomes available, leaving their codetag
uninitialized.

A clear example is in init_section_page_ext(): alloc_page_ext() calls
kmemleak_alloc().  If the slab cache has no free objects, it falls back to
the buddy allocator to allocate memory.  However, at this point page_ext
is not yet fully initialized, so these newly allocated pages have no
codetag set.  These pages may later be reclaimed by KASAN, which causes
the warning to trigger when they are freed because their codetag ref is
still empty.

Use a global array to track pages allocated before page_ext is fully
initialized.  The array size is fixed at 8192 entries, and will emit a
warning if this limit is exceeded.  When page_ext initialization
completes, set their codetag to empty to avoid warnings when they are
freed later.

This warning is only observed with CONFIG_MEM_ALLOC_PROFILING_DEBUG=Y and
mem_profiling_compressed disabled:

[    9.582133] ------------[ cut here ]------------
[    9.582137] alloc_tag was not set
[    9.582139] WARNING: ./include/linux/alloc_tag.h:164 at __pgalloc_tag_sub+0x40f/0x550, CPU#5: systemd/1
[    9.582190] CPU: 5 UID: 0 PID: 1 Comm: systemd Not tainted 7.0.0-rc4 #1 PREEMPT(lazy)
[    9.582192] Hardware name: Red Hat KVM, BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[    9.582194] RIP: 0010:__pgalloc_tag_sub+0x40f/0x550
[    9.582196] Code: 00 00 4c 29 e5 48 8b 05 1f 88 56 05 48 8d 4c ad 00 48 8d 2c c8 e9 87 fd ff ff 0f 0b 0f 0b e9 f3 fe ff ff 48 8d 3d 61 2f ed 03 &lt;67&gt; 48 0f b9 3a e9 b3 fd ff ff 0f 0b eb e4 e8 5e cd 14 02 4c 89 c7
[    9.582197] RSP: 0018:ffffc9000001f940 EFLAGS: 00010246
[    9.582200] RAX: dffffc0000000000 RBX: 1ffff92000003f2b RCX: 1ffff110200d806c
[    9.582201] RDX: ffff8881006c0360 RSI: 0000000000000004 RDI: ffffffff9bc7b460
[    9.582202] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff3a62324
[    9.582203] R10: ffffffff9d311923 R11: 0000000000000000 R12: ffffea0004001b00
[    9.582204] R13: 0000000000002000 R14: ffffea0000000000 R15: ffff8881006c0360
[    9.582206] FS:  00007ffbbcf2d940(0000) GS:ffff888450479000(0000) knlGS:0000000000000000
[    9.582208] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    9.582210] CR2: 000055ee3aa260d0 CR3: 0000000148b67005 CR4: 0000000000770ef0
[    9.582211] PKRU: 55555554
[    9.582212] Call Trace:
[    9.582213]  &lt;TASK&gt;
[    9.582214]  ? __pfx___pgalloc_tag_sub+0x10/0x10
[    9.582216]  ? check_bytes_and_report+0x68/0x140
[    9.582219]  __free_frozen_pages+0x2e4/0x1150
[    9.582221]  ? __free_slab+0xc2/0x2b0
[    9.582224]  qlist_free_all+0x4c/0xf0
[    9.582227]  kasan_quarantine_reduce+0x15d/0x180
[    9.582229]  __kasan_slab_alloc+0x69/0x90
[    9.582232]  kmem_cache_alloc_noprof+0x14a/0x500
[    9.582234]  do_getname+0x96/0x310
[    9.582237]  do_readlinkat+0x91/0x2f0
[    9.582239]  ? __pfx_do_readlinkat+0x10/0x10
[    9.582240]  ? get_random_bytes_user+0x1df/0x2c0
[    9.582244]  __x64_sys_readlinkat+0x96/0x100
[    9.582246]  do_syscall_64+0xce/0x650
[    9.582250]  ? __x64_sys_getrandom+0x13a/0x1e0
[    9.582252]  ? __pfx___x64_sys_getrandom+0x10/0x10
[    9.582254]  ? do_syscall_64+0x114/0x650
[    9.582255]  ? ksys_read+0xfc/0x1d0
[    9.582258]  ? __pfx_ksys_read+0x10/0x10
[    9.582260]  ? do_syscall_64+0x114/0x650
[    9.582262]  ? do_syscall_64+0x114/0x650
[    9.582264]  ? __pfx_fput_close_sync+0x10/0x10
[    9.582266]  ? file_close_fd_locked+0x178/0x2a0
[    9.582268]  ? __x64_sys_faccessat2+0x96/0x100
[    9.582269]  ? __x64_sys_close+0x7d/0xd0
[    9.582271]  ? do_syscall_64+0x114/0x650
[    9.582273]  ? do_syscall_64+0x114/0x650
[    9.582275]  ? clear_bhb_loop+0x50/0xa0
[    9.582277]  ? clear_bhb_loop+0x50/0xa0
[    9.582279]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[    9.582280] RIP: 0033:0x7ffbbda345ee
[    9.582282] Code: 0f 1f 40 00 48 8b 15 29 38 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 0f 1f 40 00 f3 0f 1e fa 49 89 ca b8 0b 01 00 00 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d fa 37 0d 00 f7 d8 64 89 01 48
[    9.582284] RSP: 002b:00007ffe2ad8de58 EFLAGS: 00000202 ORIG_RAX: 000000000000010b
[    9.582286] RAX: ffffffffffffffda RBX: 000055ee3aa25570 RCX: 00007ffbbda345ee
[    9.582287] RDX: 000055ee3aa25570 RSI: 00007ffe2ad8dee0 RDI: 00000000ffffff9c
[    9.582288] RBP: 0000000000001000 R08: 0000000000000003 R09: 0000000000001001
[    9.582289] R10: 0000000000001000 R11: 0000000000000202 R12: 0000000000000033
[    9.582290] R13: 00007ffe2ad8dee0 R14: 00000000ffffff9c R15: 00007ffe2ad8deb0
[    9.582292]  &lt;/TASK&gt;
[    9.582293] ---[ end trace 0000000000000000 ]---

Link: https://lore.kernel.org/20260331081312.123719-1-hao.ge@linux.dev
Fixes: dcfe378c81f72 ("lib: introduce support for page allocation tagging")
Signed-off-by: Hao Ge &lt;hao.ge@linux.dev&gt;
Suggested-by: Suren Baghdasaryan &lt;surenb@google.com&gt;
Acked-by: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Kent Overstreet &lt;kent.overstreet@linux.dev&gt;
Cc: &lt;stable@vger.kernel.org&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>
Due to initialization ordering, page_ext is allocated and initialized
relatively late during boot.  Some pages have already been allocated and
freed before page_ext becomes available, leaving their codetag
uninitialized.

A clear example is in init_section_page_ext(): alloc_page_ext() calls
kmemleak_alloc().  If the slab cache has no free objects, it falls back to
the buddy allocator to allocate memory.  However, at this point page_ext
is not yet fully initialized, so these newly allocated pages have no
codetag set.  These pages may later be reclaimed by KASAN, which causes
the warning to trigger when they are freed because their codetag ref is
still empty.

Use a global array to track pages allocated before page_ext is fully
initialized.  The array size is fixed at 8192 entries, and will emit a
warning if this limit is exceeded.  When page_ext initialization
completes, set their codetag to empty to avoid warnings when they are
freed later.

This warning is only observed with CONFIG_MEM_ALLOC_PROFILING_DEBUG=Y and
mem_profiling_compressed disabled:

[    9.582133] ------------[ cut here ]------------
[    9.582137] alloc_tag was not set
[    9.582139] WARNING: ./include/linux/alloc_tag.h:164 at __pgalloc_tag_sub+0x40f/0x550, CPU#5: systemd/1
[    9.582190] CPU: 5 UID: 0 PID: 1 Comm: systemd Not tainted 7.0.0-rc4 #1 PREEMPT(lazy)
[    9.582192] Hardware name: Red Hat KVM, BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[    9.582194] RIP: 0010:__pgalloc_tag_sub+0x40f/0x550
[    9.582196] Code: 00 00 4c 29 e5 48 8b 05 1f 88 56 05 48 8d 4c ad 00 48 8d 2c c8 e9 87 fd ff ff 0f 0b 0f 0b e9 f3 fe ff ff 48 8d 3d 61 2f ed 03 &lt;67&gt; 48 0f b9 3a e9 b3 fd ff ff 0f 0b eb e4 e8 5e cd 14 02 4c 89 c7
[    9.582197] RSP: 0018:ffffc9000001f940 EFLAGS: 00010246
[    9.582200] RAX: dffffc0000000000 RBX: 1ffff92000003f2b RCX: 1ffff110200d806c
[    9.582201] RDX: ffff8881006c0360 RSI: 0000000000000004 RDI: ffffffff9bc7b460
[    9.582202] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff3a62324
[    9.582203] R10: ffffffff9d311923 R11: 0000000000000000 R12: ffffea0004001b00
[    9.582204] R13: 0000000000002000 R14: ffffea0000000000 R15: ffff8881006c0360
[    9.582206] FS:  00007ffbbcf2d940(0000) GS:ffff888450479000(0000) knlGS:0000000000000000
[    9.582208] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    9.582210] CR2: 000055ee3aa260d0 CR3: 0000000148b67005 CR4: 0000000000770ef0
[    9.582211] PKRU: 55555554
[    9.582212] Call Trace:
[    9.582213]  &lt;TASK&gt;
[    9.582214]  ? __pfx___pgalloc_tag_sub+0x10/0x10
[    9.582216]  ? check_bytes_and_report+0x68/0x140
[    9.582219]  __free_frozen_pages+0x2e4/0x1150
[    9.582221]  ? __free_slab+0xc2/0x2b0
[    9.582224]  qlist_free_all+0x4c/0xf0
[    9.582227]  kasan_quarantine_reduce+0x15d/0x180
[    9.582229]  __kasan_slab_alloc+0x69/0x90
[    9.582232]  kmem_cache_alloc_noprof+0x14a/0x500
[    9.582234]  do_getname+0x96/0x310
[    9.582237]  do_readlinkat+0x91/0x2f0
[    9.582239]  ? __pfx_do_readlinkat+0x10/0x10
[    9.582240]  ? get_random_bytes_user+0x1df/0x2c0
[    9.582244]  __x64_sys_readlinkat+0x96/0x100
[    9.582246]  do_syscall_64+0xce/0x650
[    9.582250]  ? __x64_sys_getrandom+0x13a/0x1e0
[    9.582252]  ? __pfx___x64_sys_getrandom+0x10/0x10
[    9.582254]  ? do_syscall_64+0x114/0x650
[    9.582255]  ? ksys_read+0xfc/0x1d0
[    9.582258]  ? __pfx_ksys_read+0x10/0x10
[    9.582260]  ? do_syscall_64+0x114/0x650
[    9.582262]  ? do_syscall_64+0x114/0x650
[    9.582264]  ? __pfx_fput_close_sync+0x10/0x10
[    9.582266]  ? file_close_fd_locked+0x178/0x2a0
[    9.582268]  ? __x64_sys_faccessat2+0x96/0x100
[    9.582269]  ? __x64_sys_close+0x7d/0xd0
[    9.582271]  ? do_syscall_64+0x114/0x650
[    9.582273]  ? do_syscall_64+0x114/0x650
[    9.582275]  ? clear_bhb_loop+0x50/0xa0
[    9.582277]  ? clear_bhb_loop+0x50/0xa0
[    9.582279]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[    9.582280] RIP: 0033:0x7ffbbda345ee
[    9.582282] Code: 0f 1f 40 00 48 8b 15 29 38 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 0f 1f 40 00 f3 0f 1e fa 49 89 ca b8 0b 01 00 00 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d fa 37 0d 00 f7 d8 64 89 01 48
[    9.582284] RSP: 002b:00007ffe2ad8de58 EFLAGS: 00000202 ORIG_RAX: 000000000000010b
[    9.582286] RAX: ffffffffffffffda RBX: 000055ee3aa25570 RCX: 00007ffbbda345ee
[    9.582287] RDX: 000055ee3aa25570 RSI: 00007ffe2ad8dee0 RDI: 00000000ffffff9c
[    9.582288] RBP: 0000000000001000 R08: 0000000000000003 R09: 0000000000001001
[    9.582289] R10: 0000000000001000 R11: 0000000000000202 R12: 0000000000000033
[    9.582290] R13: 00007ffe2ad8dee0 R14: 00000000ffffff9c R15: 00007ffe2ad8deb0
[    9.582292]  &lt;/TASK&gt;
[    9.582293] ---[ end trace 0000000000000000 ]---

Link: https://lore.kernel.org/20260331081312.123719-1-hao.ge@linux.dev
Fixes: dcfe378c81f72 ("lib: introduce support for page allocation tagging")
Signed-off-by: Hao Ge &lt;hao.ge@linux.dev&gt;
Suggested-by: Suren Baghdasaryan &lt;surenb@google.com&gt;
Acked-by: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Kent Overstreet &lt;kent.overstreet@linux.dev&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/page_alloc: don't increase highatomic reserve after pcp alloc</title>
<updated>2026-04-05T20:53:36+00:00</updated>
<author>
<name>Frank van der Linden</name>
<email>fvdl@google.com</email>
</author>
<published>2026-03-20T17:34:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b480cbb071020bd590a0dc0166635b448e9fc46b'/>
<id>b480cbb071020bd590a0dc0166635b448e9fc46b</id>
<content type='text'>
Higher order GFP_ATOMIC allocations can be served through a PCP list with
ALLOC_HIGHATOMIC set.  Such an allocation can e.g.  happen if a zone is
between the low and min watermarks, and get_page_from_freelist is retried
after the alloc_flags are relaxed.

The call to reserve_highatomic_pageblock() after such a PCP allocation
will result in an increase every single time: the page from the
(unmovable) PCP list will never have migrate type MIGRATE_HIGHATOMIC,
since MIGRATE_HIGHATOMIC pages do not appear on the unmovable PCP list. 
So a new pageblock is converted to MIGRATE_HIGHATOMIC.

Eventually that leads to the maximum of 1% of the zone being used up by
(often mostly free) MIGRATE_HIGHATOMIC pageblocks, for no good reason. 
Since this space is not available for normal allocations, this wastes
memory and will push things in to reclaim too soon.

This was observed on a system that ran a test with bursts of memory
activity, paired with GFP_ATOMIC SLUB activity.  These would lead to a new
slab being allocated with GFP_ATOMIC, sometimes hitting the
get_page_from_freelist retry path by being below the low watermark.  While
the frequency of those allocations was low, it kept adding up over time,
and the number of MIGRATE_ATOMIC pageblocks kept increasing.

If a higher order atomic allocation can be served by the unmovable PCP
list, there is probably no need yet to extend the reserves.  So, move the
check and possible extension of the highatomic reserves to the buddy case
only, and do not refill the PCP list for ALLOC_HIGHATOMIC if it's empty. 
This way, the PCP list is tried for ALLOC_HIGHATOMIC for a fast atomic
allocation.  But it will immediately fall back to rmqueue_buddy() if it's
empty.  In rmqueue_buddy(), the MIGRATE_HIGHATOMIC buddy lists are tried
first (as before), and the reserves are extended only if that fails.

With this change, the test was stable.  Highatomic reserves were built up,
but to a normal level.  No highatomic failures were seen.

This is similar to the patch proposed in [1] by Zhiguo Jiang, but
re-arranged a bit.

Link: https://lkml.kernel.org/r/20260320173426.1831267-1-fvdl@google.com
Link: https://lore.kernel.org/all/20231122013925.1507-1-justinjiang@vivo.com/ [1]
Fixes: 44042b449872 ("mm/page_alloc: allow high-order pages to be stored on the per-cpu lists")
Signed-off-by: Zhiguo Jiang &lt;justinjiang@vivo.com&gt;
Signed-off-by: Frank van der Linden &lt;fvdl@google.com&gt;
Reviewed-by: Vlastimil Babka (SUSE) &lt;vbabka@kernel.org&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Michal Hocko &lt;mhocko@kernel.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Zhiguo Jiang &lt;justinjiang@vivo.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.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>
Higher order GFP_ATOMIC allocations can be served through a PCP list with
ALLOC_HIGHATOMIC set.  Such an allocation can e.g.  happen if a zone is
between the low and min watermarks, and get_page_from_freelist is retried
after the alloc_flags are relaxed.

The call to reserve_highatomic_pageblock() after such a PCP allocation
will result in an increase every single time: the page from the
(unmovable) PCP list will never have migrate type MIGRATE_HIGHATOMIC,
since MIGRATE_HIGHATOMIC pages do not appear on the unmovable PCP list. 
So a new pageblock is converted to MIGRATE_HIGHATOMIC.

Eventually that leads to the maximum of 1% of the zone being used up by
(often mostly free) MIGRATE_HIGHATOMIC pageblocks, for no good reason. 
Since this space is not available for normal allocations, this wastes
memory and will push things in to reclaim too soon.

This was observed on a system that ran a test with bursts of memory
activity, paired with GFP_ATOMIC SLUB activity.  These would lead to a new
slab being allocated with GFP_ATOMIC, sometimes hitting the
get_page_from_freelist retry path by being below the low watermark.  While
the frequency of those allocations was low, it kept adding up over time,
and the number of MIGRATE_ATOMIC pageblocks kept increasing.

If a higher order atomic allocation can be served by the unmovable PCP
list, there is probably no need yet to extend the reserves.  So, move the
check and possible extension of the highatomic reserves to the buddy case
only, and do not refill the PCP list for ALLOC_HIGHATOMIC if it's empty. 
This way, the PCP list is tried for ALLOC_HIGHATOMIC for a fast atomic
allocation.  But it will immediately fall back to rmqueue_buddy() if it's
empty.  In rmqueue_buddy(), the MIGRATE_HIGHATOMIC buddy lists are tried
first (as before), and the reserves are extended only if that fails.

With this change, the test was stable.  Highatomic reserves were built up,
but to a normal level.  No highatomic failures were seen.

This is similar to the patch proposed in [1] by Zhiguo Jiang, but
re-arranged a bit.

Link: https://lkml.kernel.org/r/20260320173426.1831267-1-fvdl@google.com
Link: https://lore.kernel.org/all/20231122013925.1507-1-justinjiang@vivo.com/ [1]
Fixes: 44042b449872 ("mm/page_alloc: allow high-order pages to be stored on the per-cpu lists")
Signed-off-by: Zhiguo Jiang &lt;justinjiang@vivo.com&gt;
Signed-off-by: Frank van der Linden &lt;fvdl@google.com&gt;
Reviewed-by: Vlastimil Babka (SUSE) &lt;vbabka@kernel.org&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Michal Hocko &lt;mhocko@kernel.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Zhiguo Jiang &lt;justinjiang@vivo.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: introduce is_pmd_order helper</title>
<updated>2026-04-05T20:53:29+00:00</updated>
<author>
<name>Nico Pache</name>
<email>npache@redhat.com</email>
</author>
<published>2026-03-25T11:40:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b90c453d2664ba445383956560581f9db708584f'/>
<id>b90c453d2664ba445383956560581f9db708584f</id>
<content type='text'>
In order to add mTHP support to khugepaged, we will often be checking if a
given order is (or is not) a PMD order.  Some places in the kernel already
use this check, so lets create a simple helper function to keep the code
clean and readable.

Link: https://lkml.kernel.org/r/20260325114022.444081-3-npache@redhat.com
Signed-off-by: Nico Pache &lt;npache@redhat.com&gt;
Acked-by: David Hildenbrand (Arm) &lt;david@kernel.org&gt;
Reviewed-by: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Reviewed-by: Dev Jain &lt;dev.jain@arm.com&gt;
Reviewed-by: Wei Yang &lt;richard.weiyang@gmail.com&gt;
Reviewed-by: Lance Yang &lt;lance.yang@linux.dev&gt;
Reviewed-by: Barry Song &lt;baohua@kernel.org&gt;
Reviewed-by: Zi Yan &lt;ziy@nvidia.com&gt;
Reviewed-by: Pedro Falcato &lt;pfalcato@suse.de&gt;
Reviewed-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Suggested-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Cc: Alistair Popple &lt;apopple@nvidia.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Anshuman Khandual &lt;anshuman.khandual@arm.com&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: Byungchul Park &lt;byungchul@sk.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Gregory Price &lt;gourry@gourry.net&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: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Joshua Hahn &lt;joshua.hahnjy@gmail.com&gt;
Cc: Kefeng Wang &lt;wangkefeng.wang@huawei.com&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Lorenzo Stoakes (Oracle) &lt;ljs@kernel.org&gt;
Cc: "Masami Hiramatsu (Google)" &lt;mhiramat@kernel.org&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Cc: Matthew Brost &lt;matthew.brost@intel.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Nanyong Sun &lt;sunnanyong@huawei.com&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Rafael Aquini &lt;raquini@redhat.com&gt;
Cc: Rakie Kim &lt;rakie.kim@sk.com&gt;
Cc: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: Shivank Garg &lt;shivankg@amd.com&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Takashi Iwai (SUSE) &lt;tiwai@suse.de&gt;
Cc: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Cc: Usama Arif &lt;usamaarif642@gmail.com&gt;
Cc: Vishal Moola (Oracle) &lt;vishal.moola@gmail.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Yang Shi &lt;yang@os.amperecomputing.com&gt;
Cc: Zach O'Keefe &lt;zokeefe@google.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>
In order to add mTHP support to khugepaged, we will often be checking if a
given order is (or is not) a PMD order.  Some places in the kernel already
use this check, so lets create a simple helper function to keep the code
clean and readable.

Link: https://lkml.kernel.org/r/20260325114022.444081-3-npache@redhat.com
Signed-off-by: Nico Pache &lt;npache@redhat.com&gt;
Acked-by: David Hildenbrand (Arm) &lt;david@kernel.org&gt;
Reviewed-by: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Reviewed-by: Dev Jain &lt;dev.jain@arm.com&gt;
Reviewed-by: Wei Yang &lt;richard.weiyang@gmail.com&gt;
Reviewed-by: Lance Yang &lt;lance.yang@linux.dev&gt;
Reviewed-by: Barry Song &lt;baohua@kernel.org&gt;
Reviewed-by: Zi Yan &lt;ziy@nvidia.com&gt;
Reviewed-by: Pedro Falcato &lt;pfalcato@suse.de&gt;
Reviewed-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Suggested-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Cc: Alistair Popple &lt;apopple@nvidia.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Anshuman Khandual &lt;anshuman.khandual@arm.com&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: Byungchul Park &lt;byungchul@sk.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Gregory Price &lt;gourry@gourry.net&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: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Joshua Hahn &lt;joshua.hahnjy@gmail.com&gt;
Cc: Kefeng Wang &lt;wangkefeng.wang@huawei.com&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Lorenzo Stoakes (Oracle) &lt;ljs@kernel.org&gt;
Cc: "Masami Hiramatsu (Google)" &lt;mhiramat@kernel.org&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Cc: Matthew Brost &lt;matthew.brost@intel.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Nanyong Sun &lt;sunnanyong@huawei.com&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Rafael Aquini &lt;raquini@redhat.com&gt;
Cc: Rakie Kim &lt;rakie.kim@sk.com&gt;
Cc: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: Shivank Garg &lt;shivankg@amd.com&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Takashi Iwai (SUSE) &lt;tiwai@suse.de&gt;
Cc: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Cc: Usama Arif &lt;usamaarif642@gmail.com&gt;
Cc: Vishal Moola (Oracle) &lt;vishal.moola@gmail.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Yang Shi &lt;yang@os.amperecomputing.com&gt;
Cc: Zach O'Keefe &lt;zokeefe@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: ratelimit min_free_kbytes adjustment messages</title>
<updated>2026-04-05T20:53:27+00:00</updated>
<author>
<name>Breno Leitao</name>
<email>leitao@debian.org</email>
</author>
<published>2026-03-17T15:33:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3203a8706e81b8d73712d46952b96eb28238c45e'/>
<id>3203a8706e81b8d73712d46952b96eb28238c45e</id>
<content type='text'>
The "raising min_free_kbytes" pr_info message in
set_recommended_min_free_kbytes() and the "min_free_kbytes is not updated
to" pr_warn in calculate_min_free_kbytes() can spam the kernel log when
called repeatedly.

Switch the pr_info in set_recommended_min_free_kbytes() and the pr_warn in
calculate_min_free_kbytes() to their _ratelimited variants to prevent the
log spam for this message.

Link: https://lkml.kernel.org/r/20260317-thp_logs-v7-4-31eb98fa5a8b@debian.org
Signed-off-by: Breno Leitao &lt;leitao@debian.org&gt;
Reviewed-by: Lorenzo Stoakes (Oracle) &lt;ljs@kernel.org&gt;
Acked-by: David Hildenbrand (Arm) &lt;david@kernel.org&gt;
Reviewed-by: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Acked-by: Zi Yan &lt;ziy@nvidia.com&gt;
Cc: Barry Song &lt;baohua@kernel.org&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Lance Yang &lt;lance.yang@linux.dev&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Nico Pache &lt;npache@redhat.com&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Usama Arif &lt;usamaarif642@gmail.com&gt;
Cc: Vlastimil Babka &lt;vbabka@kernel.org&gt;
Cc: Wei Yang &lt;richard.weiyang@gmail.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>
The "raising min_free_kbytes" pr_info message in
set_recommended_min_free_kbytes() and the "min_free_kbytes is not updated
to" pr_warn in calculate_min_free_kbytes() can spam the kernel log when
called repeatedly.

Switch the pr_info in set_recommended_min_free_kbytes() and the pr_warn in
calculate_min_free_kbytes() to their _ratelimited variants to prevent the
log spam for this message.

Link: https://lkml.kernel.org/r/20260317-thp_logs-v7-4-31eb98fa5a8b@debian.org
Signed-off-by: Breno Leitao &lt;leitao@debian.org&gt;
Reviewed-by: Lorenzo Stoakes (Oracle) &lt;ljs@kernel.org&gt;
Acked-by: David Hildenbrand (Arm) &lt;david@kernel.org&gt;
Reviewed-by: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Acked-by: Zi Yan &lt;ziy@nvidia.com&gt;
Cc: Barry Song &lt;baohua@kernel.org&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Lance Yang &lt;lance.yang@linux.dev&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Nico Pache &lt;npache@redhat.com&gt;
Cc: Ryan Roberts &lt;ryan.roberts@arm.com&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Usama Arif &lt;usamaarif642@gmail.com&gt;
Cc: Vlastimil Babka &lt;vbabka@kernel.org&gt;
Cc: Wei Yang &lt;richard.weiyang@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: introduce a new page type for page pool in page type</title>
<updated>2026-04-05T20:53:19+00:00</updated>
<author>
<name>Byungchul Park</name>
<email>byungchul@sk.com</email>
</author>
<published>2026-02-24T05:13:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=db359fccf212e7fa3136e6edbed6228475646fd7'/>
<id>db359fccf212e7fa3136e6edbed6228475646fd7</id>
<content type='text'>
Currently, the condition 'page-&gt;pp_magic == PP_SIGNATURE' is used to
determine if a page belongs to a page pool.  However, with the planned
removal of @pp_magic, we should instead leverage the page_type in struct
page, such as PGTY_netpp, for this purpose.

Introduce and use the page type APIs e.g.  PageNetpp(), __SetPageNetpp(),
and __ClearPageNetpp() instead, and remove the existing APIs accessing
@pp_magic e.g.  page_pool_page_is_pp(), netmem_or_pp_magic(), and
netmem_clear_pp_magic().

Plus, add @page_type to struct net_iov at the same offset as struct page
so as to use the page_type APIs for struct net_iov as well.  While at it,
reorder @type and @owner in struct net_iov to avoid a hole and increasing
the struct size.

This work was inspired by the following link:

  https://lore.kernel.org/all/582f41c0-2742-4400-9c81-0d46bf4e8314@gmail.com/

While at it, move the sanity check for page pool to on the free path.

[byungchul@sk.com: gate the sanity check, per Johannes]
  Link: https://lkml.kernel.org/r/20260316223113.20097-1-byungchul@sk.com
Link: https://lkml.kernel.org/r/20260224051347.19621-1-byungchul@sk.com
Co-developed-by: Pavel Begunkov &lt;asml.silence@gmail.com&gt;
Signed-off-by: Pavel Begunkov &lt;asml.silence@gmail.com&gt;
Signed-off-by: Byungchul Park &lt;byungchul@sk.com&gt;
Suggested-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: Zi Yan &lt;ziy@nvidia.com&gt;
Acked-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Reviewed-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Acked-by: Mike Rapoport (Microsoft) &lt;rppt@kernel.org&gt;
Acked-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Jesper Dangaard Brouer &lt;hawk@kernel.org&gt;
Acked-by: Ilias Apalodimas &lt;ilias.apalodimas@linaro.org&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Andrew Lunn &lt;andrew+netdev@lunn.ch&gt;
Cc: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: David Wei &lt;dw@davidwei.uk&gt;
Cc: Dragos Tatulea &lt;dtatulea@nvidia.com&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: John Fastabend &lt;john.fastabend@gmail.com&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Lorenzo Stoakes (Oracle) &lt;ljs@kernel.org&gt;
Cc: Mark Bloch &lt;mbloch@nvidia.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mina Almasry &lt;almasrymina@google.com&gt;
Cc: Paolo Abeni &lt;pabeni@redhat.com&gt;
Cc: Saeed Mahameed &lt;saeedm@nvidia.com&gt;
Cc: Simon Horman &lt;horms@kernel.org&gt;
Cc: Stanislav Fomichev &lt;sdf@fomichev.me&gt;
Cc: Stehen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Taehee Yoo &lt;ap420073@gmail.com&gt;
Cc: Tariq Toukan &lt;tariqt@nvidia.com&gt;
Cc: Usama Arif &lt;usamaarif642@gmail.com&gt;
Cc: Yu Zhao &lt;yuzhao@google.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>
Currently, the condition 'page-&gt;pp_magic == PP_SIGNATURE' is used to
determine if a page belongs to a page pool.  However, with the planned
removal of @pp_magic, we should instead leverage the page_type in struct
page, such as PGTY_netpp, for this purpose.

Introduce and use the page type APIs e.g.  PageNetpp(), __SetPageNetpp(),
and __ClearPageNetpp() instead, and remove the existing APIs accessing
@pp_magic e.g.  page_pool_page_is_pp(), netmem_or_pp_magic(), and
netmem_clear_pp_magic().

Plus, add @page_type to struct net_iov at the same offset as struct page
so as to use the page_type APIs for struct net_iov as well.  While at it,
reorder @type and @owner in struct net_iov to avoid a hole and increasing
the struct size.

This work was inspired by the following link:

  https://lore.kernel.org/all/582f41c0-2742-4400-9c81-0d46bf4e8314@gmail.com/

While at it, move the sanity check for page pool to on the free path.

[byungchul@sk.com: gate the sanity check, per Johannes]
  Link: https://lkml.kernel.org/r/20260316223113.20097-1-byungchul@sk.com
Link: https://lkml.kernel.org/r/20260224051347.19621-1-byungchul@sk.com
Co-developed-by: Pavel Begunkov &lt;asml.silence@gmail.com&gt;
Signed-off-by: Pavel Begunkov &lt;asml.silence@gmail.com&gt;
Signed-off-by: Byungchul Park &lt;byungchul@sk.com&gt;
Suggested-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: Zi Yan &lt;ziy@nvidia.com&gt;
Acked-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Reviewed-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Acked-by: Mike Rapoport (Microsoft) &lt;rppt@kernel.org&gt;
Acked-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Jesper Dangaard Brouer &lt;hawk@kernel.org&gt;
Acked-by: Ilias Apalodimas &lt;ilias.apalodimas@linaro.org&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Andrew Lunn &lt;andrew+netdev@lunn.ch&gt;
Cc: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: David Wei &lt;dw@davidwei.uk&gt;
Cc: Dragos Tatulea &lt;dtatulea@nvidia.com&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: John Fastabend &lt;john.fastabend@gmail.com&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Lorenzo Stoakes (Oracle) &lt;ljs@kernel.org&gt;
Cc: Mark Bloch &lt;mbloch@nvidia.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Mina Almasry &lt;almasrymina@google.com&gt;
Cc: Paolo Abeni &lt;pabeni@redhat.com&gt;
Cc: Saeed Mahameed &lt;saeedm@nvidia.com&gt;
Cc: Simon Horman &lt;horms@kernel.org&gt;
Cc: Stanislav Fomichev &lt;sdf@fomichev.me&gt;
Cc: Stehen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Taehee Yoo &lt;ap420073@gmail.com&gt;
Cc: Tariq Toukan &lt;tariqt@nvidia.com&gt;
Cc: Usama Arif &lt;usamaarif642@gmail.com&gt;
Cc: Yu Zhao &lt;yuzhao@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/page_alloc: remove pcpu_spin_* wrappers</title>
<updated>2026-04-05T20:53:12+00:00</updated>
<author>
<name>Vlastimil Babka</name>
<email>vbabka@kernel.org</email>
</author>
<published>2026-02-27T17:08:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e9c01915ae2b2bc9f02dbe994aca826a1021f0a2'/>
<id>e9c01915ae2b2bc9f02dbe994aca826a1021f0a2</id>
<content type='text'>
We only ever use pcpu_spin_trylock()/unlock() with struct per_cpu_pages so
refactor the helpers to remove the generic layer.

No functional change intended.

Link: https://lkml.kernel.org/r/20260227-b4-pcp-locking-cleanup-v1-3-f7e22e603447@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) &lt;vbabka@kernel.org&gt;
Suggested-by: Matthew Wilcox &lt;willy@infradead.org&gt;
Acked-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: David Hildenbrand (Arm) &lt;david@kernel.org&gt;
Cc: Mel Gorman &lt;mgorman@techsingularity.net&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.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>
We only ever use pcpu_spin_trylock()/unlock() with struct per_cpu_pages so
refactor the helpers to remove the generic layer.

No functional change intended.

Link: https://lkml.kernel.org/r/20260227-b4-pcp-locking-cleanup-v1-3-f7e22e603447@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) &lt;vbabka@kernel.org&gt;
Suggested-by: Matthew Wilcox &lt;willy@infradead.org&gt;
Acked-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Brendan Jackman &lt;jackmanb@google.com&gt;
Cc: David Hildenbrand (Arm) &lt;david@kernel.org&gt;
Cc: Mel Gorman &lt;mgorman@techsingularity.net&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
