Merge tag 'mm-hotfixes-stable-2025-05-25-00-58' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull hotfixes from Andrew Morton:
 "22 hotfixes.

  13 are cc:stable and the remainder address post-6.14 issues or aren't
  considered necessary for -stable kernels. 19 are for MM"

* tag 'mm-hotfixes-stable-2025-05-25-00-58' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (22 commits)
  mailmap: add Jarkko's employer email address
  mm: fix copy_vma() error handling for hugetlb mappings
  memcg: always call cond_resched() after fn()
  mm/hugetlb: fix kernel NULL pointer dereference when replacing free hugetlb folios
  mm: vmalloc: only zero-init on vrealloc shrink
  mm: vmalloc: actually use the in-place vrealloc region
  alloc_tag: allocate percpu counters for module tags dynamically
  module: release codetag section when module load fails
  mm/cma: make detection of highmem_start more robust
  MAINTAINERS: add mm memory policy section
  MAINTAINERS: add mm ksm section
  kasan: avoid sleepable page allocation from atomic context
  highmem: add folio_test_partial_kmap()
  MAINTAINERS: add hung-task detector section
  taskstats: fix struct taskstats breaks backward compatibility since version 15
  mm/truncate: fix out-of-bounds when doing a right-aligned split
  MAINTAINERS: add mm reclaim section
  MAINTAINERS: update page allocator section
  mm: fix VM_UFFD_MINOR == VM_SHADOW_STACK on USERFAULTFD=y && ARM64_GCS=y
  mm: mmap: map MAP_STACK to VM_NOHUGEPAGE only if THP is enabled
  ...

1 files changed, 69 insertions, 18 deletions

diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c
index 25ecc1334b67..c7f602fa7b23 100644
--- a/lib/alloc_tag.c
+++ b/lib/alloc_tag.c
@@ -350,18 +350,28 @@ static bool needs_section_mem(struct module *mod, unsigned long size)
 	return size >= sizeof(struct alloc_tag);
 }
 
-static struct alloc_tag *find_used_tag(struct alloc_tag *from, struct alloc_tag *to)
+static bool clean_unused_counters(struct alloc_tag *start_tag,
+				  struct alloc_tag *end_tag)
 {
-	while (from <= to) {
+	struct alloc_tag *tag;
+	bool ret = true;
+
+	for (tag = start_tag; tag <= end_tag; tag++) {
 		struct alloc_tag_counters counter;
 
-		counter = alloc_tag_read(from);
-		if (counter.bytes)
-			return from;
-		from++;
+		if (!tag->counters)
+			continue;
+
+		counter = alloc_tag_read(tag);
+		if (!counter.bytes) {
+			free_percpu(tag->counters);
+			tag->counters = NULL;
+		} else {
+			ret = false;
+		}
 	}
 
-	return NULL;
+	return ret;
 }
 
 /* Called with mod_area_mt locked */
@@ -371,12 +381,16 @@ static void clean_unused_module_areas_locked(void)
 	struct module *val;
 
 	mas_for_each(&mas, val, module_tags.size) {
+		struct alloc_tag *start_tag;
+		struct alloc_tag *end_tag;
+
 		if (val != &unloaded_mod)
 			continue;
 
 		/* Release area if all tags are unused */
-		if (!find_used_tag((struct alloc_tag *)(module_tags.start_addr + mas.index),
-				   (struct alloc_tag *)(module_tags.start_addr + mas.last)))
+		start_tag = (struct alloc_tag *)(module_tags.start_addr + mas.index);
+		end_tag = (struct alloc_tag *)(module_tags.start_addr + mas.last);
+		if (clean_unused_counters(start_tag, end_tag))
 			mas_erase(&mas);
 	}
 }
@@ -561,7 +575,8 @@ unlock:
 static void release_module_tags(struct module *mod, bool used)
 {
 	MA_STATE(mas, &mod_area_mt, module_tags.size, module_tags.size);
-	struct alloc_tag *tag;
+	struct alloc_tag *start_tag;
+	struct alloc_tag *end_tag;
 	struct module *val;
 
 	mas_lock(&mas);
@@ -575,15 +590,22 @@ static void release_module_tags(struct module *mod, bool used)
 	if (!used)
 		goto release_area;
 
-	/* Find out if the area is used */
-	tag = find_used_tag((struct alloc_tag *)(module_tags.start_addr + mas.index),
-			    (struct alloc_tag *)(module_tags.start_addr + mas.last));
-	if (tag) {
-		struct alloc_tag_counters counter = alloc_tag_read(tag);
+	start_tag = (struct alloc_tag *)(module_tags.start_addr + mas.index);
+	end_tag = (struct alloc_tag *)(module_tags.start_addr + mas.last);
+	if (!clean_unused_counters(start_tag, end_tag)) {
+		struct alloc_tag *tag;
+
+		for (tag = start_tag; tag <= end_tag; tag++) {
+			struct alloc_tag_counters counter;
+
+			if (!tag->counters)
+				continue;
 
-		pr_info("%s:%u module %s func:%s has %llu allocated at module unload\n",
-			tag->ct.filename, tag->ct.lineno, tag->ct.modname,
-			tag->ct.function, counter.bytes);
+			counter = alloc_tag_read(tag);
+			pr_info("%s:%u module %s func:%s has %llu allocated at module unload\n",
+				tag->ct.filename, tag->ct.lineno, tag->ct.modname,
+				tag->ct.function, counter.bytes);
+		}
 	} else {
 		used = false;
 	}
@@ -596,6 +618,34 @@ out:
 	mas_unlock(&mas);
 }
 
+static void load_module(struct module *mod, struct codetag *start, struct codetag *stop)
+{
+	/* Allocate module alloc_tag percpu counters */
+	struct alloc_tag *start_tag;
+	struct alloc_tag *stop_tag;
+	struct alloc_tag *tag;
+
+	if (!mod)
+		return;
+
+	start_tag = ct_to_alloc_tag(start);
+	stop_tag = ct_to_alloc_tag(stop);
+	for (tag = start_tag; tag < stop_tag; tag++) {
+		WARN_ON(tag->counters);
+		tag->counters = alloc_percpu(struct alloc_tag_counters);
+		if (!tag->counters) {
+			while (--tag >= start_tag) {
+				free_percpu(tag->counters);
+				tag->counters = NULL;
+			}
+			shutdown_mem_profiling(true);
+			pr_err("Failed to allocate memory for allocation tag percpu counters in the module %s. Memory allocation profiling is disabled!\n",
+			       mod->name);
+			break;
+		}
+	}
+}
+
 static void replace_module(struct module *mod, struct module *new_mod)
 {
 	MA_STATE(mas, &mod_area_mt, 0, module_tags.size);
@@ -757,6 +807,7 @@ static int __init alloc_tag_init(void)
 		.needs_section_mem	= needs_section_mem,
 		.alloc_section_mem	= reserve_module_tags,
 		.free_section_mem	= release_module_tags,
+		.module_load		= load_module,
 		.module_replaced	= replace_module,
 #endif
 	};