Merge tag 'mm-stable-2024-11-18-19-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - The series "zram: optimal post-processing target selection" from
   Sergey Senozhatsky improves zram's post-processing selection
   algorithm. This leads to improved memory savings.

 - Wei Yang has gone to town on the mapletree code, contributing several
   series which clean up the implementation:
	- "refine mas_mab_cp()"
	- "Reduce the space to be cleared for maple_big_node"
	- "maple_tree: simplify mas_push_node()"
	- "Following cleanup after introduce mas_wr_store_type()"
	- "refine storing null"

 - The series "selftests/mm: hugetlb_fault_after_madv improvements" from
   David Hildenbrand fixes this selftest for s390.

 - The series "introduce pte_offset_map_{ro|rw}_nolock()" from Qi Zheng
   implements some rationaizations and cleanups in the page mapping
   code.

 - The series "mm: optimize shadow entries removal" from Shakeel Butt
   optimizes the file truncation code by speeding up the handling of
   shadow entries.

 - The series "Remove PageKsm()" from Matthew Wilcox completes the
   migration of this flag over to being a folio-based flag.

 - The series "Unify hugetlb into arch_get_unmapped_area functions" from
   Oscar Salvador implements a bunch of consolidations and cleanups in
   the hugetlb code.

 - The series "Do not shatter hugezeropage on wp-fault" from Dev Jain
   takes away the wp-fault time practice of turning a huge zero page
   into small pages. Instead we replace the whole thing with a THP. More
   consistent cleaner and potentiall saves a large number of pagefaults.

 - The series "percpu: Add a test case and fix for clang" from Andy
   Shevchenko enhances and fixes the kernel's built in percpu test code.

 - The series "mm/mremap: Remove extra vma tree walk" from Liam Howlett
   optimizes mremap() by avoiding doing things which we didn't need to
   do.

 - The series "Improve the tmpfs large folio read performance" from
   Baolin Wang teaches tmpfs to copy data into userspace at the folio
   size rather than as individual pages. A 20% speedup was observed.

 - The series "mm/damon/vaddr: Fix issue in
   damon_va_evenly_split_region()" fro Zheng Yejian fixes DAMON
   splitting.

 - The series "memcg-v1: fully deprecate charge moving" from Shakeel
   Butt removes the long-deprecated memcgv2 charge moving feature.

 - The series "fix error handling in mmap_region() and refactor" from
   Lorenzo Stoakes cleanup up some of the mmap() error handling and
   addresses some potential performance issues.

 - The series "x86/module: use large ROX pages for text allocations"
   from Mike Rapoport teaches x86 to use large pages for
   read-only-execute module text.

 - The series "page allocation tag compression" from Suren Baghdasaryan
   is followon maintenance work for the new page allocation profiling
   feature.

 - The series "page->index removals in mm" from Matthew Wilcox remove
   most references to page->index in mm/. A slow march towards shrinking
   struct page.

 - The series "damon/{self,kunit}tests: minor fixups for DAMON debugfs
   interface tests" from Andrew Paniakin performs maintenance work for
   DAMON's self testing code.

 - The series "mm: zswap swap-out of large folios" from Kanchana Sridhar
   improves zswap's batching of compression and decompression. It is a
   step along the way towards using Intel IAA hardware acceleration for
   this zswap operation.

 - The series "kasan: migrate the last module test to kunit" from
   Sabyrzhan Tasbolatov completes the migration of the KASAN built-in
   tests over to the KUnit framework.

 - The series "implement lightweight guard pages" from Lorenzo Stoakes
   permits userapace to place fault-generating guard pages within a
   single VMA, rather than requiring that multiple VMAs be created for
   this. Improved efficiencies for userspace memory allocators are
   expected.

 - The series "memcg: tracepoint for flushing stats" from JP Kobryn uses
   tracepoints to provide increased visibility into memcg stats flushing
   activity.

 - The series "zram: IDLE flag handling fixes" from Sergey Senozhatsky
   fixes a zram buglet which potentially affected performance.

 - The series "mm: add more kernel parameters to control mTHP" from
   Maíra Canal enhances our ability to control/configuremultisize THP
   from the kernel boot command line.

 - The series "kasan: few improvements on kunit tests" from Sabyrzhan
   Tasbolatov has a couple of fixups for the KASAN KUnit tests.

 - The series "mm/list_lru: Split list_lru lock into per-cgroup scope"
   from Kairui Song optimizes list_lru memory utilization when lockdep
   is enabled.

* tag 'mm-stable-2024-11-18-19-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (215 commits)
  cma: enforce non-zero pageblock_order during cma_init_reserved_mem()
  mm/kfence: add a new kunit test test_use_after_free_read_nofault()
  zram: fix NULL pointer in comp_algorithm_show()
  memcg/hugetlb: add hugeTLB counters to memcg
  vmstat: call fold_vm_zone_numa_events() before show per zone NUMA event
  mm: mmap_lock: check trace_mmap_lock_$type_enabled() instead of regcount
  zram: ZRAM_DEF_COMP should depend on ZRAM
  MAINTAINERS/MEMORY MANAGEMENT: add document files for mm
  Docs/mm/damon: recommend academic papers to read and/or cite
  mm: define general function pXd_init()
  kmemleak: iommu/iova: fix transient kmemleak false positive
  mm/list_lru: simplify the list_lru walk callback function
  mm/list_lru: split the lock to per-cgroup scope
  mm/list_lru: simplify reparenting and initial allocation
  mm/list_lru: code clean up for reparenting
  mm/list_lru: don't export list_lru_add
  mm/list_lru: don't pass unnecessary key parameters
  kasan: add kunit tests for kmalloc_track_caller, kmalloc_node_track_caller
  kasan: change kasan_atomics kunit test as KUNIT_CASE_SLOW
  kasan: use EXPORT_SYMBOL_IF_KUNIT to export symbols
  ...

Author: torvalds

Documentation/admin-guide/blockdev/zram.rst

@@ -47,6 +47,8 @@ The list of possible return codes:
 -ENOMEM	  zram was not able to allocate enough memory to fulfil your
 	  needs.
 -EINVAL	  invalid input has been provided.
+-EAGAIN	  re-try operation later (e.g. when attempting to run recompress
+	  and writeback simultaneously).
 ========  =============================================================
 
 If you use 'echo', the returned value is set by the 'echo' utility,

Documentation/admin-guide/cgroup-v1/memory.rst

@@ -90,9 +90,7 @@ Brief summary of control files.
                                      used.
  memory.swappiness		     set/show swappiness parameter of vmscan
 				     (See sysctl's vm.swappiness)
- memory.move_charge_at_immigrate     set/show controls of moving charges
-                                     This knob is deprecated and shouldn't be
-                                     used.
+ memory.move_charge_at_immigrate     This knob is deprecated.
  memory.oom_control		     set/show oom controls.
                                      This knob is deprecated and shouldn't be
                                      used.
@@ -243,10 +241,6 @@ behind this approach is that a cgroup that aggressively uses a shared
 page will eventually get charged for it (once it is uncharged from
 the cgroup that brought it in -- this will happen on memory pressure).
 
-But see :ref:`section 8.2 <cgroup-v1-memory-movable-charges>` when moving a
-task to another cgroup, its pages may be recharged to the new cgroup, if
-move_charge_at_immigrate has been chosen.
-
 2.4 Swap Extension
 --------------------------------------
 
@@ -756,78 +750,8 @@ If we want to change this to 1G, we can at any time use::
 
 THIS IS DEPRECATED!
 
-It's expensive and unreliable! It's better practice to launch workload
-tasks directly from inside their target cgroup. Use dedicated workload
-cgroups to allow fine-grained policy adjustments without having to
-move physical pages between control domains.
-
-Users can move charges associated with a task along with task migration, that
-is, uncharge task's pages from the old cgroup and charge them to the new cgroup.
-This feature is not supported in !CONFIG_MMU environments because of lack of
-page tables.
-
-8.1 Interface
--------------
-
-This feature is disabled by default. It can be enabled (and disabled again) by
-writing to memory.move_charge_at_immigrate of the destination cgroup.
-
-If you want to enable it::
-
-	# echo (some positive value) > memory.move_charge_at_immigrate
-
-.. note::
-      Each bits of move_charge_at_immigrate has its own meaning about what type
-      of charges should be moved. See :ref:`section 8.2
-      <cgroup-v1-memory-movable-charges>` for details.
-
-.. note::
-      Charges are moved only when you move mm->owner, in other words,
-      a leader of a thread group.
-
-.. note::
-      If we cannot find enough space for the task in the destination cgroup, we
-      try to make space by reclaiming memory. Task migration may fail if we
-      cannot make enough space.
-
-.. note::
-      It can take several seconds if you move charges much.
-
-And if you want disable it again::
-
-	# echo 0 > memory.move_charge_at_immigrate
-
-.. _cgroup-v1-memory-movable-charges:
-
-8.2 Type of charges which can be moved
---------------------------------------
-
-Each bit in move_charge_at_immigrate has its own meaning about what type of
-charges should be moved. But in any case, it must be noted that an account of
-a page or a swap can be moved only when it is charged to the task's current
-(old) memory cgroup.
-
-+---+--------------------------------------------------------------------------+
-|bit| what type of charges would be moved ?                                    |
-+===+==========================================================================+
-| 0 | A charge of an anonymous page (or swap of it) used by the target task.   |
-|   | You must enable Swap Extension (see 2.4) to enable move of swap charges. |
-+---+--------------------------------------------------------------------------+
-| 1 | A charge of file pages (normal file, tmpfs file (e.g. ipc shared memory) |
-|   | and swaps of tmpfs file) mmapped by the target task. Unlike the case of  |
-|   | anonymous pages, file pages (and swaps) in the range mmapped by the task |
-|   | will be moved even if the task hasn't done page fault, i.e. they might   |
-|   | not be the task's "RSS", but other task's "RSS" that maps the same file. |
-|   | The mapcount of the page is ignored (the page can be moved independent   |
-|   | of the mapcount). You must enable Swap Extension (see 2.4) to            |
-|   | enable move of swap charges.                                             |
-+---+--------------------------------------------------------------------------+
-
-8.3 TODO
---------
-
-- All of moving charge operations are done under cgroup_mutex. It's not good
-  behavior to hold the mutex too long, so we may need some trick.
+Reading memory.move_charge_at_immigrate will always return 0 and writing
+to it will always return -EINVAL.
 
 9. Memory thresholds
 ====================

Documentation/admin-guide/cgroup-v2.rst

@@ -1655,6 +1655,11 @@ The following nested keys are defined.
 	  pgdemote_khugepaged
 		Number of pages demoted by khugepaged.
 
+	  hugetlb
+		Amount of memory used by hugetlb pages. This metric only shows
+		up if hugetlb usage is accounted for in memory.current (i.e.
+		cgroup is mounted with the memory_hugetlb_accounting option).
+
   memory.numa_stat
 	A read-only nested-keyed file which exists on non-root cgroups.
 

Documentation/admin-guide/kernel-parameters.txt

@@ -6711,6 +6711,16 @@
 			Force threading of all interrupt handlers except those
 			marked explicitly IRQF_NO_THREAD.
 
+	thp_shmem=	[KNL]
+			Format: <size>[KMG],<size>[KMG]:<policy>;<size>[KMG]-<size>[KMG]:<policy>
+			Control the default policy of each hugepage size for the
+			internal shmem mount. <policy> is one of policies available
+			for the shmem mount ("always", "inherit", "never", "within_size",
+			and "advise").
+			It can be used multiple times for multiple shmem THP sizes.
+			See Documentation/admin-guide/mm/transhuge.rst for more
+			details.
+
 	topology=	[S390,EARLY]
 			Format: {off | on}
 			Specify if the kernel should make use of the cpu
@@ -6952,6 +6962,13 @@
 			See Documentation/admin-guide/mm/transhuge.rst
 			for more details.
 
+	transparent_hugepage_shmem= [KNL]
+			Format: [always|within_size|advise|never|deny|force]
+			Can be used to control the hugepage allocation policy for
+			the internal shmem mount.
+			See Documentation/admin-guide/mm/transhuge.rst
+			for more details.
+
 	trusted.source=	[KEYS]
 			Format: <string>
 			This parameter identifies the trust source as a backend

Documentation/admin-guide/mm/transhuge.rst

@@ -326,6 +326,29 @@ PMD_ORDER THP policy will be overridden. If the policy for PMD_ORDER
 is not defined within a valid ``thp_anon``, its policy will default to
 ``never``.
 
+Similarly to ``transparent_hugepage``, you can control the hugepage
+allocation policy for the internal shmem mount by using the kernel parameter
+``transparent_hugepage_shmem=<policy>``, where ``<policy>`` is one of the
+seven valid policies for shmem (``always``, ``within_size``, ``advise``,
+``never``, ``deny``, and ``force``).
+
+In the same manner as ``thp_anon`` controls each supported anonymous THP
+size, ``thp_shmem`` controls each supported shmem THP size. ``thp_shmem``
+has the same format as ``thp_anon``, but also supports the policy
+``within_size``.
+
+``thp_shmem=`` may be specified multiple times to configure all THP sizes
+as required. If ``thp_shmem=`` is specified at least once, any shmem THP
+sizes not explicitly configured on the command line are implicitly set to
+``never``.
+
+``transparent_hugepage_shmem`` setting only affects the global toggle. If
+``thp_shmem`` is not specified, PMD_ORDER hugepage will default to
+``inherit``. However, if a valid ``thp_shmem`` setting is provided by the
+user, the PMD_ORDER hugepage policy will be overridden. If the policy for
+PMD_ORDER is not defined within a valid ``thp_shmem``, its policy will
+default to ``never``.
+
 Hugepages in tmpfs/shmem
 ========================
 
@@ -530,10 +553,18 @@ anon_fault_fallback_charge
 	instead falls back to using huge pages with lower orders or
 	small pages even though the allocation was successful.
 
-swpout
-	is incremented every time a huge page is swapped out in one
+zswpout
+	is incremented every time a huge page is swapped out to zswap in one
 	piece without splitting.
 
+swpin
+	is incremented every time a huge page is swapped in from a non-zswap
+	swap device in one piece.
+
+swpout
+	is incremented every time a huge page is swapped out to a non-zswap
+	swap device in one piece without splitting.
+
 swpout_fallback
 	is incremented if a huge page has to be split before swapout.
 	Usually because failed to allocate some continuous swap space

Documentation/dev-tools/kasan.rst

@@ -511,19 +511,14 @@ Tests
 ~~~~~
 
 There are KASAN tests that allow verifying that KASAN works and can detect
-certain types of memory corruptions. The tests consist of two parts:
+certain types of memory corruptions.
 
-1. Tests that are integrated with the KUnit Test Framework. Enabled with
-``CONFIG_KASAN_KUNIT_TEST``. These tests can be run and partially verified
+All KASAN tests are integrated with the KUnit Test Framework and can be enabled
+via ``CONFIG_KASAN_KUNIT_TEST``. The tests can be run and partially verified
 automatically in a few different ways; see the instructions below.
 
-2. Tests that are currently incompatible with KUnit. Enabled with
-``CONFIG_KASAN_MODULE_TEST`` and can only be run as a module. These tests can
-only be verified manually by loading the kernel module and inspecting the
-kernel log for KASAN reports.
-
-Each KUnit-compatible KASAN test prints one of multiple KASAN reports if an
-error is detected. Then the test prints its number and status.
+Each KASAN test prints one of multiple KASAN reports if an error is detected.
+Then the test prints its number and status.
 
 When a test passes::
 
@@ -550,16 +545,16 @@ Or, if one of the tests failed::
 
         not ok 1 - kasan
 
-There are a few ways to run KUnit-compatible KASAN tests.
+There are a few ways to run the KASAN tests.
 
 1. Loadable module
 
-   With ``CONFIG_KUNIT`` enabled, KASAN-KUnit tests can be built as a loadable
-   module and run by loading ``kasan_test.ko`` with ``insmod`` or ``modprobe``.
+   With ``CONFIG_KUNIT`` enabled, the tests can be built as a loadable module
+   and run by loading ``kasan_test.ko`` with ``insmod`` or ``modprobe``.
 
 2. Built-In
 
-   With ``CONFIG_KUNIT`` built-in, KASAN-KUnit tests can be built-in as well.
+   With ``CONFIG_KUNIT`` built-in, the tests can be built-in as well.
    In this case, the tests will run at boot as a late-init call.
 
 3. Using kunit_tool

Documentation/dev-tools/kmemleak.rst

@@ -161,6 +161,7 @@ See the include/linux/kmemleak.h header for the functions prototype.
 - ``kmemleak_free_percpu``	 - notify of a percpu memory block freeing
 - ``kmemleak_update_trace``	 - update object allocation stack trace
 - ``kmemleak_not_leak``	 - mark an object as not a leak
+- ``kmemleak_transient_leak``	 - mark an object as a transient leak
 - ``kmemleak_ignore``		 - do not scan or report an object as leak
 - ``kmemleak_scan_area``	 - add scan areas inside a memory block
 - ``kmemleak_no_scan``	 - do not scan a memory block

Documentation/mm/allocation-profiling.rst

@@ -18,12 +18,17 @@ kconfig options:
   missing annotation
 
 Boot parameter:
-  sysctl.vm.mem_profiling=0|1|never
+  sysctl.vm.mem_profiling={0|1|never}[,compressed]
 
   When set to "never", memory allocation profiling overhead is minimized and it
   cannot be enabled at runtime (sysctl becomes read-only).
   When CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=y, default value is "1".
   When CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=n, default value is "never".
+  "compressed" optional parameter will try to store page tag references in a
+  compact format, avoiding page extensions. This results in improved performance
+  and memory consumption, however it might fail depending on system configuration.
+  If compression fails, a warning is issued and memory allocation profiling gets
+  disabled.
 
 sysctl:
   /proc/sys/vm/mem_profiling

Documentation/mm/damon/index.rst

@@ -37,3 +37,9 @@ with no code but simple configurations.
 
 To utilize and control DAMON from the user-space, please refer to the
 administration :doc:`guide </admin-guide/mm/damon/index>`.
+
+If you prefer academic papers for reading and citations, please use the papers
+from `HPDC'22 <https://dl.acm.org/doi/abs/10.1145/3502181.3531466>`_ and
+`Middleware19 Industry <https://dl.acm.org/doi/abs/10.1145/3366626.3368125>`_ .
+Note that those cover DAMON implementations in Linux v5.16 and v5.15,
+respectively.

Documentation/mm/split_page_table_lock.rst

@@ -16,9 +16,13 @@ There are helpers to lock/unlock a table and other accessor functions:
  - pte_offset_map_lock()
 	maps PTE and takes PTE table lock, returns pointer to PTE with
 	pointer to its PTE table lock, or returns NULL if no PTE table;
- - pte_offset_map_nolock()
+ - pte_offset_map_ro_nolock()
 	maps PTE, returns pointer to PTE with pointer to its PTE table
 	lock (not taken), or returns NULL if no PTE table;
+ - pte_offset_map_rw_nolock()
+	maps PTE, returns pointer to PTE with pointer to its PTE table
+	lock (not taken) and the value of its pmd entry, or returns NULL
+	if no PTE table;
  - pte_offset_map()
 	maps PTE, returns pointer to PTE, or returns NULL if no PTE table;
  - pte_unmap()