Merge tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Daniel Verkamp has contributed a memfd series ("mm/memfd: add
   F_SEAL_EXEC") which permits the setting of the memfd execute bit at
   memfd creation time, with the option of sealing the state of the X
   bit.

 - Peter Xu adds a patch series ("mm/hugetlb: Make huge_pte_offset()
   thread-safe for pmd unshare") which addresses a rare race condition
   related to PMD unsharing.

 - Several folioification patch serieses from Matthew Wilcox, Vishal
   Moola, Sidhartha Kumar and Lorenzo Stoakes

 - Johannes Weiner has a series ("mm: push down lock_page_memcg()")
   which does perform some memcg maintenance and cleanup work.

 - SeongJae Park has added DAMOS filtering to DAMON, with the series
   "mm/damon/core: implement damos filter".

   These filters provide users with finer-grained control over DAMOS's
   actions. SeongJae has also done some DAMON cleanup work.

 - Kairui Song adds a series ("Clean up and fixes for swap").

 - Vernon Yang contributed the series "Clean up and refinement for maple
   tree".

 - Yu Zhao has contributed the "mm: multi-gen LRU: memcg LRU" series. It
   adds to MGLRU an LRU of memcgs, to improve the scalability of global
   reclaim.

 - David Hildenbrand has added some userfaultfd cleanup work in the
   series "mm: uffd-wp + change_protection() cleanups".

 - Christoph Hellwig has removed the generic_writepages() library
   function in the series "remove generic_writepages".

 - Baolin Wang has performed some maintenance on the compaction code in
   his series "Some small improvements for compaction".

 - Sidhartha Kumar is doing some maintenance work on struct page in his
   series "Get rid of tail page fields".

 - David Hildenbrand contributed some cleanup, bugfixing and
   generalization of pte management and of pte debugging in his series
   "mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with
   swap PTEs".

 - Mel Gorman and Neil Brown have removed the __GFP_ATOMIC allocation
   flag in the series "Discard __GFP_ATOMIC".

 - Sergey Senozhatsky has improved zsmalloc's memory utilization with
   his series "zsmalloc: make zspage chain size configurable".

 - Joey Gouly has added prctl() support for prohibiting the creation of
   writeable+executable mappings.

   The previous BPF-based approach had shortcomings. See "mm: In-kernel
   support for memory-deny-write-execute (MDWE)".

 - Waiman Long did some kmemleak cleanup and bugfixing in the series
   "mm/kmemleak: Simplify kmemleak_cond_resched() & fix UAF".

 - T.J. Alumbaugh has contributed some MGLRU cleanup work in his series
   "mm: multi-gen LRU: improve".

 - Jiaqi Yan has provided some enhancements to our memory error
   statistics reporting, mainly by presenting the statistics on a
   per-node basis. See the series "Introduce per NUMA node memory error
   statistics".

 - Mel Gorman has a second and hopefully final shot at fixing a CPU-hog
   regression in compaction via his series "Fix excessive CPU usage
   during compaction".

 - Christoph Hellwig does some vmalloc maintenance work in the series
   "cleanup vfree and vunmap".

 - Christoph Hellwig has removed block_device_operations.rw_page() in
   ths series "remove ->rw_page".

 - We get some maple_tree improvements and cleanups in Liam Howlett's
   series "VMA tree type safety and remove __vma_adjust()".

 - Suren Baghdasaryan has done some work on the maintainability of our
   vm_flags handling in the series "introduce vm_flags modifier
   functions".

 - Some pagemap cleanup and generalization work in Mike Rapoport's
   series "mm, arch: add generic implementation of pfn_valid() for
   FLATMEM" and "fixups for generic implementation of pfn_valid()"

 - Baoquan He has done some work to make /proc/vmallocinfo and
   /proc/kcore better represent the real state of things in his series
   "mm/vmalloc.c: allow vread() to read out vm_map_ram areas".

 - Jason Gunthorpe rationalized the GUP system's interface to the rest
   of the kernel in the series "Simplify the external interface for
   GUP".

 - SeongJae Park wishes to migrate people from DAMON's debugfs interface
   over to its sysfs interface. To support this, we'll temporarily be
   printing warnings when people use the debugfs interface. See the
   series "mm/damon: deprecate DAMON debugfs interface".

 - Andrey Konovalov provided the accurately named "lib/stackdepot: fixes
   and clean-ups" series.

 - Huang Ying has provided a dramatic reduction in migration's TLB flush
   IPI rates with the series "migrate_pages(): batch TLB flushing".

 - Arnd Bergmann has some objtool fixups in "objtool warning fixes".

* tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (505 commits)
  include/linux/migrate.h: remove unneeded externs
  mm/memory_hotplug: cleanup return value handing in do_migrate_range()
  mm/uffd: fix comment in handling pte markers
  mm: change to return bool for isolate_movable_page()
  mm: hugetlb: change to return bool for isolate_hugetlb()
  mm: change to return bool for isolate_lru_page()
  mm: change to return bool for folio_isolate_lru()
  objtool: add UACCESS exceptions for __tsan_volatile_read/write
  kmsan: disable ftrace in kmsan core code
  kasan: mark addr_has_metadata __always_inline
  mm: memcontrol: rename memcg_kmem_enabled()
  sh: initialize max_mapnr
  m68k/nommu: add missing definition of ARCH_PFN_OFFSET
  mm: percpu: fix incorrect size in pcpu_obj_full_size()
  maple_tree: reduce stack usage with gcc-9 and earlier
  mm: page_alloc: call panic() when memoryless node allocation fails
  mm: multi-gen LRU: avoid futile retries
  migrate_pages: move THP/hugetlb migration support check to simplify code
  migrate_pages: batch flushing TLB
  migrate_pages: share more code between _unmap and _move
  ...

1 files changed, 42 insertions, 43 deletions

diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 55dc8b8b0616..a2d34226e3c8 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -13,11 +13,12 @@
  *
  * The following locks and mutexes are used by kmemleak:
  *
- * - kmemleak_lock (raw_spinlock_t): protects the object_list modifications and
- *   accesses to the object_tree_root (or object_phys_tree_root). The
- *   object_list is the main list holding the metadata (struct kmemleak_object)
- *   for the allocated memory blocks. The object_tree_root and object_phys_tree_root
- *   are red black trees used to look-up metadata based on a pointer to the
+ * - kmemleak_lock (raw_spinlock_t): protects the object_list as well as
+ *   del_state modifications and accesses to the object_tree_root (or
+ *   object_phys_tree_root). The object_list is the main list holding the
+ *   metadata (struct kmemleak_object) for the allocated memory blocks.
+ *   The object_tree_root and object_phys_tree_root are red
+ *   black trees used to look-up metadata based on a pointer to the
  *   corresponding memory block. The object_phys_tree_root is for objects
  *   allocated with physical address. The kmemleak_object structures are
  *   added to the object_list and object_tree_root (or object_phys_tree_root)
@@ -148,6 +149,7 @@ struct kmemleak_object {
 	struct rcu_head rcu;		/* object_list lockless traversal */
 	/* object usage count; object freed when use_count == 0 */
 	atomic_t use_count;
+	unsigned int del_state;		/* deletion state */
 	unsigned long pointer;
 	size_t size;
 	/* pass surplus references to this pointer */
@@ -177,6 +179,11 @@ struct kmemleak_object {
 /* flag set for object allocated with physical address */
 #define OBJECT_PHYS		(1 << 4)
 
+/* set when __remove_object() called */
+#define DELSTATE_REMOVED	(1 << 0)
+/* set to temporarily prevent deletion from object_list */
+#define DELSTATE_NO_DELETE	(1 << 1)
+
 #define HEX_PREFIX		"    "
 /* number of bytes to print per line; must be 16 or 32 */
 #define HEX_ROW_SIZE		16
@@ -571,7 +578,9 @@ static void __remove_object(struct kmemleak_object *object)
 	rb_erase(&object->rb_node, object->flags & OBJECT_PHYS ?
 				   &object_phys_tree_root :
 				   &object_tree_root);
-	list_del_rcu(&object->object_list);
+	if (!(object->del_state & DELSTATE_NO_DELETE))
+		list_del_rcu(&object->object_list);
+	object->del_state |= DELSTATE_REMOVED;
 }
 
 /*
@@ -643,6 +652,7 @@ static void __create_object(unsigned long ptr, size_t size,
 	object->count = 0;			/* white color initially */
 	object->jiffies = jiffies;
 	object->checksum = 0;
+	object->del_state = 0;
 
 	/* task information */
 	if (in_hardirq()) {
@@ -1472,22 +1482,30 @@ static void scan_gray_list(void)
 /*
  * Conditionally call resched() in an object iteration loop while making sure
  * that the given object won't go away without RCU read lock by performing a
- * get_object() if !pinned.
- *
- * Return: false if can't do a cond_resched() due to get_object() failure
- *	   true otherwise
+ * get_object() if necessaary.
  */
-static bool kmemleak_cond_resched(struct kmemleak_object *object, bool pinned)
+static void kmemleak_cond_resched(struct kmemleak_object *object)
 {
-	if (!pinned && !get_object(object))
-		return false;
+	if (!get_object(object))
+		return;	/* Try next object */
+
+	raw_spin_lock_irq(&kmemleak_lock);
+	if (object->del_state & DELSTATE_REMOVED)
+		goto unlock_put;	/* Object removed */
+	object->del_state |= DELSTATE_NO_DELETE;
+	raw_spin_unlock_irq(&kmemleak_lock);
 
 	rcu_read_unlock();
 	cond_resched();
 	rcu_read_lock();
-	if (!pinned)
-		put_object(object);
-	return true;
+
+	raw_spin_lock_irq(&kmemleak_lock);
+	if (object->del_state & DELSTATE_REMOVED)
+		list_del_rcu(&object->object_list);
+	object->del_state &= ~DELSTATE_NO_DELETE;
+unlock_put:
+	raw_spin_unlock_irq(&kmemleak_lock);
+	put_object(object);
 }
 
 /*
@@ -1501,15 +1519,12 @@ static void kmemleak_scan(void)
 	struct zone *zone;
 	int __maybe_unused i;
 	int new_leaks = 0;
-	int loop_cnt = 0;
 
 	jiffies_last_scan = jiffies;
 
 	/* prepare the kmemleak_object's */
 	rcu_read_lock();
 	list_for_each_entry_rcu(object, &object_list, object_list) {
-		bool obj_pinned = false;
-
 		raw_spin_lock_irq(&object->lock);
 #ifdef DEBUG
 		/*
@@ -1535,19 +1550,13 @@ static void kmemleak_scan(void)
 
 		/* reset the reference count (whiten the object) */
 		object->count = 0;
-		if (color_gray(object) && get_object(object)) {
+		if (color_gray(object) && get_object(object))
 			list_add_tail(&object->gray_list, &gray_list);
-			obj_pinned = true;
-		}
 
 		raw_spin_unlock_irq(&object->lock);
 
-		/*
-		 * Do a cond_resched() every 64k objects to avoid soft lockup.
-		 */
-		if (!(++loop_cnt & 0xffff) &&
-		    !kmemleak_cond_resched(object, obj_pinned))
-			loop_cnt--; /* Try again on next object */
+		if (need_resched())
+			kmemleak_cond_resched(object);
 	}
 	rcu_read_unlock();
 
@@ -1614,14 +1623,9 @@ static void kmemleak_scan(void)
 	 * scan and color them gray until the next scan.
 	 */
 	rcu_read_lock();
-	loop_cnt = 0;
 	list_for_each_entry_rcu(object, &object_list, object_list) {
-		/*
-		 * Do a cond_resched() every 64k objects to avoid soft lockup.
-		 */
-		if (!(++loop_cnt & 0xffff) &&
-		    !kmemleak_cond_resched(object, false))
-			loop_cnt--;	/* Try again on next object */
+		if (need_resched())
+			kmemleak_cond_resched(object);
 
 		/*
 		 * This is racy but we can save the overhead of lock/unlock
@@ -1656,14 +1660,9 @@ static void kmemleak_scan(void)
 	 * Scanning result reporting.
 	 */
 	rcu_read_lock();
-	loop_cnt = 0;
 	list_for_each_entry_rcu(object, &object_list, object_list) {
-		/*
-		 * Do a cond_resched() every 64k objects to avoid soft lockup.
-		 */
-		if (!(++loop_cnt & 0xffff) &&
-		    !kmemleak_cond_resched(object, false))
-			loop_cnt--;	/* Try again on next object */
+		if (need_resched())
+			kmemleak_cond_resched(object);
 
 		/*
 		 * This is racy but we can save the overhead of lock/unlock
@@ -2072,7 +2071,7 @@ static int __init kmemleak_boot_config(char *str)
 		kmemleak_disable();
 	else if (strcmp(str, "on") == 0) {
 		kmemleak_skip_disable = 1;
-		stack_depot_want_early_init();
+		stack_depot_request_early_init();
 	}
 	else
 		return -EINVAL;