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
  ...

1 files changed, 90 insertions, 0 deletions

diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c
index 31561e0e1a0d..704cb1093ae8 100644
--- a/lib/test_maple_tree.c
+++ b/lib/test_maple_tree.c
@@ -1387,6 +1387,92 @@ static noinline void __init check_prev_entry(struct maple_tree *mt)
 	mas_unlock(&mas);
 }
 
+static noinline void __init check_store_null(struct maple_tree *mt)
+{
+	MA_STATE(mas, mt, 0, ULONG_MAX);
+
+	/*
+	 * Store NULL at range [0, ULONG_MAX] to an empty tree should result
+	 * in an empty tree
+	 */
+	mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE);
+	mas_lock(&mas);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, !mtree_empty(mt));
+	mas_unlock(&mas);
+	mtree_destroy(mt);
+
+	/*
+	 * Store NULL at any range to an empty tree should result in an empty
+	 * tree
+	 */
+	mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE);
+	mas_lock(&mas);
+	mas_set_range(&mas, 3, 10);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, !mtree_empty(mt));
+	mas_unlock(&mas);
+	mtree_destroy(mt);
+
+	/*
+	 * Store NULL at range [0, ULONG_MAX] to a single entry tree should
+	 * result in an empty tree
+	 */
+	mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE);
+	mas_lock(&mas);
+	mas_set(&mas, 0);
+	mas_store_gfp(&mas, &mas, GFP_KERNEL);
+	mas_set_range(&mas, 0, ULONG_MAX);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, !mtree_empty(mt));
+	mas_unlock(&mas);
+	mtree_destroy(mt);
+
+	/*
+	 * Store NULL at range [0, n] to a single entry tree should
+	 * result in an empty tree
+	 */
+	mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE);
+	mas_lock(&mas);
+	mas_set(&mas, 0);
+	mas_store_gfp(&mas, &mas, GFP_KERNEL);
+	mas_set_range(&mas, 0, 5);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, !mtree_empty(mt));
+	mas_unlock(&mas);
+	mtree_destroy(mt);
+
+	/*
+	 * Store NULL at range [m, n] where m > 0 to a single entry tree
+	 * should still be a single entry tree
+	 */
+	mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE);
+	mas_lock(&mas);
+	mas_set(&mas, 0);
+	mas_store_gfp(&mas, &mas, GFP_KERNEL);
+	mas_set_range(&mas, 2, 5);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, mtree_empty(mt));
+//	MT_BUG_ON(mt, xa_is_node(mas_root(&mas)));
+	mas_unlock(&mas);
+	mtree_destroy(mt);
+
+	/*
+	 * Store NULL at range [0, ULONG_MAX] to a tree with node should
+	 * result in an empty tree
+	 */
+	mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE);
+	mas_lock(&mas);
+	mas_set_range(&mas, 1, 3);
+	mas_store_gfp(&mas, &mas, GFP_KERNEL);
+//	MT_BUG_ON(mt, !xa_is_node(mas_root(&mas)));
+	mas_set_range(&mas, 0, ULONG_MAX);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, !mtree_empty(mt));
+	mas_unlock(&mas);
+	mtree_destroy(mt);
+}
+
 static noinline void __init check_root_expand(struct maple_tree *mt)
 {
 	MA_STATE(mas, mt, 0, 0);
@@ -3711,6 +3797,10 @@ static int __init maple_tree_seed(void)
 #endif
 
 	mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
+	check_store_null(&tree);
+	mtree_destroy(&tree);
+
+	mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
 	check_root_expand(&tree);
 	mtree_destroy(&tree);