Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 17dd883..2446076 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -1,23 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * mm/kmemleak.c
  *
  * Copyright (C) 2008 ARM Limited
  * Written by Catalin Marinas <catalin.marinas@arm.com>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- *
  * For more information on the algorithm and kmemleak usage, please see
  * Documentation/dev-tools/kmemleak.rst.
  *
@@ -86,12 +73,13 @@
 #include <linux/seq_file.h>
 #include <linux/cpumask.h>
 #include <linux/spinlock.h>
+#include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/rcupdate.h>
 #include <linux/stacktrace.h>
 #include <linux/cache.h>
 #include <linux/percpu.h>
-#include <linux/bootmem.h>
+#include <linux/memblock.h>
 #include <linux/pfn.h>
 #include <linux/mmzone.h>
 #include <linux/slab.h>
@@ -126,7 +114,7 @@
 /* GFP bitmask for kmemleak internal allocations */
 #define gfp_kmemleak_mask(gfp)	(((gfp) & (GFP_KERNEL | GFP_ATOMIC)) | \
 				 __GFP_NORETRY | __GFP_NOMEMALLOC | \
-				 __GFP_NOWARN | __GFP_NOFAIL)
+				 __GFP_NOWARN)
 
 /* scanning area inside a memory block */
 struct kmemleak_scan_area {
@@ -180,7 +168,10 @@
 #define OBJECT_REPORTED		(1 << 1)
 /* flag set to not scan the object */
 #define OBJECT_NO_SCAN		(1 << 2)
+/* flag set to fully scan the object when scan_area allocation failed */
+#define OBJECT_FULL_SCAN	(1 << 3)
 
+#define HEX_PREFIX		"    "
 /* number of bytes to print per line; must be 16 or 32 */
 #define HEX_ROW_SIZE		16
 /* number of bytes to print at a time (1, 2, 4, 8) */
@@ -194,6 +185,10 @@
 static LIST_HEAD(object_list);
 /* the list of gray-colored objects (see color_gray comment below) */
 static LIST_HEAD(gray_list);
+/* memory pool allocation */
+static struct kmemleak_object mem_pool[CONFIG_DEBUG_KMEMLEAK_MEM_POOL_SIZE];
+static int mem_pool_free_count = ARRAY_SIZE(mem_pool);
+static LIST_HEAD(mem_pool_free_list);
 /* search tree for object boundaries */
 static struct rb_root object_tree_root = RB_ROOT;
 /* rw_lock protecting the access to object_list and object_tree_root */
@@ -204,13 +199,11 @@
 static struct kmem_cache *scan_area_cache;
 
 /* set if tracing memory operations is enabled */
-static int kmemleak_enabled;
+static int kmemleak_enabled = 1;
 /* same as above but only for the kmemleak_free() callback */
-static int kmemleak_free_enabled;
+static int kmemleak_free_enabled = 1;
 /* set in the late_initcall if there were no errors */
 static int kmemleak_initialized;
-/* enables or disables early logging of the memory operations */
-static int kmemleak_early_log = 1;
 /* set if a kmemleak warning was issued */
 static int kmemleak_warning;
 /* set if a fatal kmemleak error has occurred */
@@ -235,48 +228,8 @@
 /* If there are leaks that can be reported */
 static bool kmemleak_found_leaks;
 
-/*
- * Early object allocation/freeing logging. Kmemleak is initialized after the
- * kernel allocator. However, both the kernel allocator and kmemleak may
- * allocate memory blocks which need to be tracked. Kmemleak defines an
- * arbitrary buffer to hold the allocation/freeing information before it is
- * fully initialized.
- */
-
-/* kmemleak operation type for early logging */
-enum {
-	KMEMLEAK_ALLOC,
-	KMEMLEAK_ALLOC_PERCPU,
-	KMEMLEAK_FREE,
-	KMEMLEAK_FREE_PART,
-	KMEMLEAK_FREE_PERCPU,
-	KMEMLEAK_NOT_LEAK,
-	KMEMLEAK_IGNORE,
-	KMEMLEAK_SCAN_AREA,
-	KMEMLEAK_NO_SCAN,
-	KMEMLEAK_SET_EXCESS_REF
-};
-
-/*
- * Structure holding the information passed to kmemleak callbacks during the
- * early logging.
- */
-struct early_log {
-	int op_type;			/* kmemleak operation type */
-	int min_count;			/* minimum reference count */
-	const void *ptr;		/* allocated/freed memory block */
-	union {
-		size_t size;		/* memory block size */
-		unsigned long excess_ref; /* surplus reference passing */
-	};
-	unsigned long trace[MAX_TRACE];	/* stack trace */
-	unsigned int trace_len;		/* stack trace length */
-};
-
-/* early logging buffer and current position */
-static struct early_log
-	early_log[CONFIG_DEBUG_KMEMLEAK_EARLY_LOG_SIZE] __initdata;
-static int crt_early_log __initdata;
+static bool kmemleak_verbose;
+module_param_named(verbose, kmemleak_verbose, bool, 0600);
 
 static void kmemleak_disable(void);
 
@@ -299,6 +252,25 @@
 	kmemleak_disable();		\
 } while (0)
 
+#define warn_or_seq_printf(seq, fmt, ...)	do {	\
+	if (seq)					\
+		seq_printf(seq, fmt, ##__VA_ARGS__);	\
+	else						\
+		pr_warn(fmt, ##__VA_ARGS__);		\
+} while (0)
+
+static void warn_or_seq_hex_dump(struct seq_file *seq, int prefix_type,
+				 int rowsize, int groupsize, const void *buf,
+				 size_t len, bool ascii)
+{
+	if (seq)
+		seq_hex_dump(seq, HEX_PREFIX, prefix_type, rowsize, groupsize,
+			     buf, len, ascii);
+	else
+		print_hex_dump(KERN_WARNING, pr_fmt(HEX_PREFIX), prefix_type,
+			       rowsize, groupsize, buf, len, ascii);
+}
+
 /*
  * Printing of the objects hex dump to the seq file. The number of lines to be
  * printed is limited to HEX_MAX_LINES to prevent seq file spamming. The
@@ -314,10 +286,10 @@
 	/* limit the number of lines to HEX_MAX_LINES */
 	len = min_t(size_t, object->size, HEX_MAX_LINES * HEX_ROW_SIZE);
 
-	seq_printf(seq, "  hex dump (first %zu bytes):\n", len);
+	warn_or_seq_printf(seq, "  hex dump (first %zu bytes):\n", len);
 	kasan_disable_current();
-	seq_hex_dump(seq, "    ", DUMP_PREFIX_NONE, HEX_ROW_SIZE,
-		     HEX_GROUP_SIZE, ptr, len, HEX_ASCII);
+	warn_or_seq_hex_dump(seq, DUMP_PREFIX_NONE, HEX_ROW_SIZE,
+			     HEX_GROUP_SIZE, ptr, len, HEX_ASCII);
 	kasan_enable_current();
 }
 
@@ -365,17 +337,17 @@
 	int i;
 	unsigned int msecs_age = jiffies_to_msecs(jiffies - object->jiffies);
 
-	seq_printf(seq, "unreferenced object 0x%08lx (size %zu):\n",
+	warn_or_seq_printf(seq, "unreferenced object 0x%08lx (size %zu):\n",
 		   object->pointer, object->size);
-	seq_printf(seq, "  comm \"%s\", pid %d, jiffies %lu (age %d.%03ds)\n",
+	warn_or_seq_printf(seq, "  comm \"%s\", pid %d, jiffies %lu (age %d.%03ds)\n",
 		   object->comm, object->pid, object->jiffies,
 		   msecs_age / 1000, msecs_age % 1000);
 	hex_dump_object(seq, object);
-	seq_printf(seq, "  backtrace:\n");
+	warn_or_seq_printf(seq, "  backtrace:\n");
 
 	for (i = 0; i < object->trace_len; i++) {
 		void *ptr = (void *)object->trace[i];
-		seq_printf(seq, "    [<%p>] %pS\n", ptr, ptr);
+		warn_or_seq_printf(seq, "    [<%p>] %pS\n", ptr, ptr);
 	}
 }
 
@@ -386,11 +358,6 @@
  */
 static void dump_object_info(struct kmemleak_object *object)
 {
-	struct stack_trace trace;
-
-	trace.nr_entries = object->trace_len;
-	trace.entries = object->trace;
-
 	pr_notice("Object 0x%08lx (size %zu):\n",
 		  object->pointer, object->size);
 	pr_notice("  comm \"%s\", pid %d, jiffies %lu\n",
@@ -400,7 +367,7 @@
 	pr_notice("  flags = 0x%x\n", object->flags);
 	pr_notice("  checksum = %u\n", object->checksum);
 	pr_notice("  backtrace:\n");
-	print_stack_trace(&trace, 4);
+	stack_trace_print(object->trace, object->trace_len, 4);
 }
 
 /*
@@ -444,6 +411,54 @@
 }
 
 /*
+ * Memory pool allocation and freeing. kmemleak_lock must not be held.
+ */
+static struct kmemleak_object *mem_pool_alloc(gfp_t gfp)
+{
+	unsigned long flags;
+	struct kmemleak_object *object;
+
+	/* try the slab allocator first */
+	if (object_cache) {
+		object = kmem_cache_alloc(object_cache, gfp_kmemleak_mask(gfp));
+		if (object)
+			return object;
+	}
+
+	/* slab allocation failed, try the memory pool */
+	write_lock_irqsave(&kmemleak_lock, flags);
+	object = list_first_entry_or_null(&mem_pool_free_list,
+					  typeof(*object), object_list);
+	if (object)
+		list_del(&object->object_list);
+	else if (mem_pool_free_count)
+		object = &mem_pool[--mem_pool_free_count];
+	else
+		pr_warn_once("Memory pool empty, consider increasing CONFIG_DEBUG_KMEMLEAK_MEM_POOL_SIZE\n");
+	write_unlock_irqrestore(&kmemleak_lock, flags);
+
+	return object;
+}
+
+/*
+ * Return the object to either the slab allocator or the memory pool.
+ */
+static void mem_pool_free(struct kmemleak_object *object)
+{
+	unsigned long flags;
+
+	if (object < mem_pool || object >= mem_pool + ARRAY_SIZE(mem_pool)) {
+		kmem_cache_free(object_cache, object);
+		return;
+	}
+
+	/* add the object to the memory pool free list */
+	write_lock_irqsave(&kmemleak_lock, flags);
+	list_add(&object->object_list, &mem_pool_free_list);
+	write_unlock_irqrestore(&kmemleak_lock, flags);
+}
+
+/*
  * RCU callback to free a kmemleak_object.
  */
 static void free_object_rcu(struct rcu_head *rcu)
@@ -461,7 +476,7 @@
 		hlist_del(&area->node);
 		kmem_cache_free(scan_area_cache, area);
 	}
-	kmem_cache_free(object_cache, object);
+	mem_pool_free(object);
 }
 
 /*
@@ -479,7 +494,15 @@
 	/* should only get here after delete_object was called */
 	WARN_ON(object->flags & OBJECT_ALLOCATED);
 
-	call_rcu(&object->rcu, free_object_rcu);
+	/*
+	 * It may be too early for the RCU callbacks, however, there is no
+	 * concurrent object_list traversal when !object_cache and all objects
+	 * came from the memory pool. Free the object directly.
+	 */
+	if (object_cache)
+		call_rcu(&object->rcu, free_object_rcu);
+	else
+		free_object_rcu(&object->rcu);
 }
 
 /*
@@ -504,6 +527,16 @@
 }
 
 /*
+ * Remove an object from the object_tree_root and object_list. Must be called
+ * with the kmemleak_lock held _if_ kmemleak is still enabled.
+ */
+static void __remove_object(struct kmemleak_object *object)
+{
+	rb_erase(&object->rb_node, &object_tree_root);
+	list_del_rcu(&object->object_list);
+}
+
+/*
  * Look up an object in the object search tree and remove it from both
  * object_tree_root and object_list. The returned object's use_count should be
  * at least 1, as initially set by create_object().
@@ -515,10 +548,8 @@
 
 	write_lock_irqsave(&kmemleak_lock, flags);
 	object = lookup_object(ptr, alias);
-	if (object) {
-		rb_erase(&object->rb_node, &object_tree_root);
-		list_del_rcu(&object->object_list);
-	}
+	if (object)
+		__remove_object(object);
 	write_unlock_irqrestore(&kmemleak_lock, flags);
 
 	return object;
@@ -529,15 +560,7 @@
  */
 static int __save_stack_trace(unsigned long *trace)
 {
-	struct stack_trace stack_trace;
-
-	stack_trace.max_entries = MAX_TRACE;
-	stack_trace.nr_entries = 0;
-	stack_trace.entries = trace;
-	stack_trace.skip = 2;
-	save_stack_trace(&stack_trace);
-
-	return stack_trace.nr_entries;
+	return stack_trace_save(trace, MAX_TRACE, 2);
 }
 
 /*
@@ -550,8 +573,9 @@
 	unsigned long flags;
 	struct kmemleak_object *object, *parent;
 	struct rb_node **link, *rb_parent;
+	unsigned long untagged_ptr;
 
-	object = kmem_cache_alloc(object_cache, gfp_kmemleak_mask(gfp));
+	object = mem_pool_alloc(gfp);
 	if (!object) {
 		pr_warn("Cannot allocate a kmemleak_object structure\n");
 		kmemleak_disable();
@@ -576,7 +600,7 @@
 	if (in_irq()) {
 		object->pid = 0;
 		strncpy(object->comm, "hardirq", sizeof(object->comm));
-	} else if (in_softirq()) {
+	} else if (in_serving_softirq()) {
 		object->pid = 0;
 		strncpy(object->comm, "softirq", sizeof(object->comm));
 	} else {
@@ -595,8 +619,9 @@
 
 	write_lock_irqsave(&kmemleak_lock, flags);
 
-	min_addr = min(min_addr, ptr);
-	max_addr = max(max_addr, ptr + size);
+	untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr);
+	min_addr = min(min_addr, untagged_ptr);
+	max_addr = max(max_addr, untagged_ptr + size);
 	link = &object_tree_root.rb_node;
 	rb_parent = NULL;
 	while (*link) {
@@ -689,9 +714,7 @@
 	/*
 	 * Create one or two objects that may result from the memory block
 	 * split. Note that partial freeing is only done by free_bootmem() and
-	 * this happens before kmemleak_init() is called. The path below is
-	 * only executed during early log recording in kmemleak_init(), so
-	 * GFP_KERNEL is enough.
+	 * this happens before kmemleak_init() is called.
 	 */
 	start = object->pointer;
 	end = object->pointer + object->size;
@@ -763,7 +786,7 @@
 {
 	unsigned long flags;
 	struct kmemleak_object *object;
-	struct kmemleak_scan_area *area;
+	struct kmemleak_scan_area *area = NULL;
 
 	object = find_and_get_object(ptr, 1);
 	if (!object) {
@@ -772,13 +795,16 @@
 		return;
 	}
 
-	area = kmem_cache_alloc(scan_area_cache, gfp_kmemleak_mask(gfp));
-	if (!area) {
-		pr_warn("Cannot allocate a scan area\n");
-		goto out;
-	}
+	if (scan_area_cache)
+		area = kmem_cache_alloc(scan_area_cache, gfp_kmemleak_mask(gfp));
 
 	spin_lock_irqsave(&object->lock, flags);
+	if (!area) {
+		pr_warn_once("Cannot allocate a scan area, scanning the full object\n");
+		/* mark the object for full scan to avoid false positives */
+		object->flags |= OBJECT_FULL_SCAN;
+		goto out_unlock;
+	}
 	if (size == SIZE_MAX) {
 		size = object->pointer + object->size - ptr;
 	} else if (ptr + size > object->pointer + object->size) {
@@ -795,7 +821,6 @@
 	hlist_add_head(&area->node, &object->area_list);
 out_unlock:
 	spin_unlock_irqrestore(&object->lock, flags);
-out:
 	put_object(object);
 }
 
@@ -845,86 +870,6 @@
 	put_object(object);
 }
 
-/*
- * Log an early kmemleak_* call to the early_log buffer. These calls will be
- * processed later once kmemleak is fully initialized.
- */
-static void __init log_early(int op_type, const void *ptr, size_t size,
-			     int min_count)
-{
-	unsigned long flags;
-	struct early_log *log;
-
-	if (kmemleak_error) {
-		/* kmemleak stopped recording, just count the requests */
-		crt_early_log++;
-		return;
-	}
-
-	if (crt_early_log >= ARRAY_SIZE(early_log)) {
-		crt_early_log++;
-		kmemleak_disable();
-		return;
-	}
-
-	/*
-	 * There is no need for locking since the kernel is still in UP mode
-	 * at this stage. Disabling the IRQs is enough.
-	 */
-	local_irq_save(flags);
-	log = &early_log[crt_early_log];
-	log->op_type = op_type;
-	log->ptr = ptr;
-	log->size = size;
-	log->min_count = min_count;
-	log->trace_len = __save_stack_trace(log->trace);
-	crt_early_log++;
-	local_irq_restore(flags);
-}
-
-/*
- * Log an early allocated block and populate the stack trace.
- */
-static void early_alloc(struct early_log *log)
-{
-	struct kmemleak_object *object;
-	unsigned long flags;
-	int i;
-
-	if (!kmemleak_enabled || !log->ptr || IS_ERR(log->ptr))
-		return;
-
-	/*
-	 * RCU locking needed to ensure object is not freed via put_object().
-	 */
-	rcu_read_lock();
-	object = create_object((unsigned long)log->ptr, log->size,
-			       log->min_count, GFP_ATOMIC);
-	if (!object)
-		goto out;
-	spin_lock_irqsave(&object->lock, flags);
-	for (i = 0; i < log->trace_len; i++)
-		object->trace[i] = log->trace[i];
-	object->trace_len = log->trace_len;
-	spin_unlock_irqrestore(&object->lock, flags);
-out:
-	rcu_read_unlock();
-}
-
-/*
- * Log an early allocated block and populate the stack trace.
- */
-static void early_alloc_percpu(struct early_log *log)
-{
-	unsigned int cpu;
-	const void __percpu *ptr = log->ptr;
-
-	for_each_possible_cpu(cpu) {
-		log->ptr = per_cpu_ptr(ptr, cpu);
-		early_alloc(log);
-	}
-}
-
 /**
  * kmemleak_alloc - register a newly allocated object
  * @ptr:	pointer to beginning of the object
@@ -946,8 +891,6 @@
 
 	if (kmemleak_enabled && ptr && !IS_ERR(ptr))
 		create_object((unsigned long)ptr, size, min_count, gfp);
-	else if (kmemleak_early_log)
-		log_early(KMEMLEAK_ALLOC, ptr, size, min_count);
 }
 EXPORT_SYMBOL_GPL(kmemleak_alloc);
 
@@ -975,8 +918,6 @@
 		for_each_possible_cpu(cpu)
 			create_object((unsigned long)per_cpu_ptr(ptr, cpu),
 				      size, 0, gfp);
-	else if (kmemleak_early_log)
-		log_early(KMEMLEAK_ALLOC_PERCPU, ptr, size, 0);
 }
 EXPORT_SYMBOL_GPL(kmemleak_alloc_percpu);
 
@@ -1001,11 +942,6 @@
 		create_object((unsigned long)area->addr, size, 2, gfp);
 		object_set_excess_ref((unsigned long)area,
 				      (unsigned long)area->addr);
-	} else if (kmemleak_early_log) {
-		log_early(KMEMLEAK_ALLOC, area->addr, size, 2);
-		/* reusing early_log.size for storing area->addr */
-		log_early(KMEMLEAK_SET_EXCESS_REF,
-			  area, (unsigned long)area->addr, 0);
 	}
 }
 EXPORT_SYMBOL_GPL(kmemleak_vmalloc);
@@ -1023,8 +959,6 @@
 
 	if (kmemleak_free_enabled && ptr && !IS_ERR(ptr))
 		delete_object_full((unsigned long)ptr);
-	else if (kmemleak_early_log)
-		log_early(KMEMLEAK_FREE, ptr, 0, 0);
 }
 EXPORT_SYMBOL_GPL(kmemleak_free);
 
@@ -1043,8 +977,6 @@
 
 	if (kmemleak_enabled && ptr && !IS_ERR(ptr))
 		delete_object_part((unsigned long)ptr, size);
-	else if (kmemleak_early_log)
-		log_early(KMEMLEAK_FREE_PART, ptr, size, 0);
 }
 EXPORT_SYMBOL_GPL(kmemleak_free_part);
 
@@ -1065,8 +997,6 @@
 		for_each_possible_cpu(cpu)
 			delete_object_full((unsigned long)per_cpu_ptr(ptr,
 								      cpu));
-	else if (kmemleak_early_log)
-		log_early(KMEMLEAK_FREE_PERCPU, ptr, 0, 0);
 }
 EXPORT_SYMBOL_GPL(kmemleak_free_percpu);
 
@@ -1117,8 +1047,6 @@
 
 	if (kmemleak_enabled && ptr && !IS_ERR(ptr))
 		make_gray_object((unsigned long)ptr);
-	else if (kmemleak_early_log)
-		log_early(KMEMLEAK_NOT_LEAK, ptr, 0, 0);
 }
 EXPORT_SYMBOL(kmemleak_not_leak);
 
@@ -1137,8 +1065,6 @@
 
 	if (kmemleak_enabled && ptr && !IS_ERR(ptr))
 		make_black_object((unsigned long)ptr);
-	else if (kmemleak_early_log)
-		log_early(KMEMLEAK_IGNORE, ptr, 0, 0);
 }
 EXPORT_SYMBOL(kmemleak_ignore);
 
@@ -1159,8 +1085,6 @@
 
 	if (kmemleak_enabled && ptr && size && !IS_ERR(ptr))
 		add_scan_area((unsigned long)ptr, size, gfp);
-	else if (kmemleak_early_log)
-		log_early(KMEMLEAK_SCAN_AREA, ptr, size, 0);
 }
 EXPORT_SYMBOL(kmemleak_scan_area);
 
@@ -1179,8 +1103,6 @@
 
 	if (kmemleak_enabled && ptr && !IS_ERR(ptr))
 		object_no_scan((unsigned long)ptr);
-	else if (kmemleak_early_log)
-		log_early(KMEMLEAK_NO_SCAN, ptr, 0, 0);
 }
 EXPORT_SYMBOL(kmemleak_no_scan);
 
@@ -1309,6 +1231,7 @@
 	unsigned long *start = PTR_ALIGN(_start, BYTES_PER_POINTER);
 	unsigned long *end = _end - (BYTES_PER_POINTER - 1);
 	unsigned long flags;
+	unsigned long untagged_ptr;
 
 	read_lock_irqsave(&kmemleak_lock, flags);
 	for (ptr = start; ptr < end; ptr++) {
@@ -1323,7 +1246,8 @@
 		pointer = *ptr;
 		kasan_enable_current();
 
-		if (pointer < min_addr || pointer >= max_addr)
+		untagged_ptr = (unsigned long)kasan_reset_tag((void *)pointer);
+		if (untagged_ptr < min_addr || untagged_ptr >= max_addr)
 			continue;
 
 		/*
@@ -1373,6 +1297,7 @@
 /*
  * Scan a large memory block in MAX_SCAN_SIZE chunks to reduce the latency.
  */
+#ifdef CONFIG_SMP
 static void scan_large_block(void *start, void *end)
 {
 	void *next;
@@ -1384,6 +1309,7 @@
 		cond_resched();
 	}
 }
+#endif
 
 /*
  * Scan a memory block corresponding to a kmemleak_object. A condition is
@@ -1404,7 +1330,8 @@
 	if (!(object->flags & OBJECT_ALLOCATED))
 		/* already freed object */
 		goto out;
-	if (hlist_empty(&object->area_list)) {
+	if (hlist_empty(&object->area_list) ||
+	    object->flags & OBJECT_FULL_SCAN) {
 		void *start = (void *)object->pointer;
 		void *end = (void *)(object->pointer + object->size);
 		void *next;
@@ -1501,11 +1428,6 @@
 	}
 	rcu_read_unlock();
 
-	/* data/bss scanning */
-	scan_large_block(_sdata, _edata);
-	scan_large_block(__bss_start, __bss_stop);
-	scan_large_block(__start_ro_after_init, __end_ro_after_init);
-
 #ifdef CONFIG_SMP
 	/* per-cpu sections scanning */
 	for_each_possible_cpu(i)
@@ -1523,11 +1445,14 @@
 		unsigned long pfn;
 
 		for (pfn = start_pfn; pfn < end_pfn; pfn++) {
-			struct page *page;
+			struct page *page = pfn_to_online_page(pfn);
 
-			if (!pfn_valid(pfn))
+			if (!page)
 				continue;
-			page = pfn_to_page(pfn);
+
+			/* only scan pages belonging to this node */
+			if (page_to_nid(page) != i)
+				continue;
 			/* only scan if page is in use */
 			if (page_count(page) == 0)
 				continue;
@@ -1598,6 +1523,10 @@
 		if (unreferenced_object(object) &&
 		    !(object->flags & OBJECT_REPORTED)) {
 			object->flags |= OBJECT_REPORTED;
+
+			if (kmemleak_verbose)
+				print_unreferenced(NULL, object);
+
 			new_leaks++;
 		}
 		spin_unlock_irqrestore(&object->lock, flags);
@@ -1619,7 +1548,7 @@
  */
 static int kmemleak_scan_thread(void *arg)
 {
-	static int first_run = 1;
+	static int first_run = IS_ENABLED(CONFIG_DEBUG_KMEMLEAK_AUTO_SCAN);
 
 	pr_info("Automatic memory scanning thread started\n");
 	set_user_nice(current, 10);
@@ -1860,7 +1789,7 @@
 	}
 
 	if (!kmemleak_enabled) {
-		ret = -EBUSY;
+		ret = -EPERM;
 		goto out;
 	}
 
@@ -1913,12 +1842,16 @@
 
 static void __kmemleak_do_cleanup(void)
 {
-	struct kmemleak_object *object;
+	struct kmemleak_object *object, *tmp;
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(object, &object_list, object_list)
-		delete_object_full(object->pointer);
-	rcu_read_unlock();
+	/*
+	 * Kmemleak has already been disabled, no need for RCU list traversal
+	 * or kmemleak_lock held.
+	 */
+	list_for_each_entry_safe(object, tmp, &object_list, object_list) {
+		__remove_object(object);
+		__delete_object(object);
+	}
 }
 
 /*
@@ -1987,105 +1920,37 @@
 }
 early_param("kmemleak", kmemleak_boot_config);
 
-static void __init print_log_trace(struct early_log *log)
-{
-	struct stack_trace trace;
-
-	trace.nr_entries = log->trace_len;
-	trace.entries = log->trace;
-
-	pr_notice("Early log backtrace:\n");
-	print_stack_trace(&trace, 2);
-}
-
 /*
  * Kmemleak initialization.
  */
 void __init kmemleak_init(void)
 {
-	int i;
-	unsigned long flags;
-
 #ifdef CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF
 	if (!kmemleak_skip_disable) {
-		kmemleak_early_log = 0;
 		kmemleak_disable();
 		return;
 	}
 #endif
 
+	if (kmemleak_error)
+		return;
+
 	jiffies_min_age = msecs_to_jiffies(MSECS_MIN_AGE);
 	jiffies_scan_wait = msecs_to_jiffies(SECS_SCAN_WAIT * 1000);
 
 	object_cache = KMEM_CACHE(kmemleak_object, SLAB_NOLEAKTRACE);
 	scan_area_cache = KMEM_CACHE(kmemleak_scan_area, SLAB_NOLEAKTRACE);
 
-	if (crt_early_log > ARRAY_SIZE(early_log))
-		pr_warn("Early log buffer exceeded (%d), please increase DEBUG_KMEMLEAK_EARLY_LOG_SIZE\n",
-			crt_early_log);
-
-	/* the kernel is still in UP mode, so disabling the IRQs is enough */
-	local_irq_save(flags);
-	kmemleak_early_log = 0;
-	if (kmemleak_error) {
-		local_irq_restore(flags);
-		return;
-	} else {
-		kmemleak_enabled = 1;
-		kmemleak_free_enabled = 1;
-	}
-	local_irq_restore(flags);
-
-	/*
-	 * This is the point where tracking allocations is safe. Automatic
-	 * scanning is started during the late initcall. Add the early logged
-	 * callbacks to the kmemleak infrastructure.
-	 */
-	for (i = 0; i < crt_early_log; i++) {
-		struct early_log *log = &early_log[i];
-
-		switch (log->op_type) {
-		case KMEMLEAK_ALLOC:
-			early_alloc(log);
-			break;
-		case KMEMLEAK_ALLOC_PERCPU:
-			early_alloc_percpu(log);
-			break;
-		case KMEMLEAK_FREE:
-			kmemleak_free(log->ptr);
-			break;
-		case KMEMLEAK_FREE_PART:
-			kmemleak_free_part(log->ptr, log->size);
-			break;
-		case KMEMLEAK_FREE_PERCPU:
-			kmemleak_free_percpu(log->ptr);
-			break;
-		case KMEMLEAK_NOT_LEAK:
-			kmemleak_not_leak(log->ptr);
-			break;
-		case KMEMLEAK_IGNORE:
-			kmemleak_ignore(log->ptr);
-			break;
-		case KMEMLEAK_SCAN_AREA:
-			kmemleak_scan_area(log->ptr, log->size, GFP_KERNEL);
-			break;
-		case KMEMLEAK_NO_SCAN:
-			kmemleak_no_scan(log->ptr);
-			break;
-		case KMEMLEAK_SET_EXCESS_REF:
-			object_set_excess_ref((unsigned long)log->ptr,
-					      log->excess_ref);
-			break;
-		default:
-			kmemleak_warn("Unknown early log operation: %d\n",
-				      log->op_type);
-		}
-
-		if (kmemleak_warning) {
-			print_log_trace(log);
-			kmemleak_warning = 0;
-		}
-	}
+	/* register the data/bss sections */
+	create_object((unsigned long)_sdata, _edata - _sdata,
+		      KMEMLEAK_GREY, GFP_ATOMIC);
+	create_object((unsigned long)__bss_start, __bss_stop - __bss_start,
+		      KMEMLEAK_GREY, GFP_ATOMIC);
+	/* only register .data..ro_after_init if not within .data */
+	if (__start_ro_after_init < _sdata || __end_ro_after_init > _edata)
+		create_object((unsigned long)__start_ro_after_init,
+			      __end_ro_after_init - __start_ro_after_init,
+			      KMEMLEAK_GREY, GFP_ATOMIC);
 }
 
 /*
@@ -2093,14 +1958,9 @@
  */
 static int __init kmemleak_late_init(void)
 {
-	struct dentry *dentry;
-
 	kmemleak_initialized = 1;
 
-	dentry = debugfs_create_file("kmemleak", 0644, NULL, NULL,
-				     &kmemleak_fops);
-	if (!dentry)
-		pr_warn("Failed to create the debugfs kmemleak file\n");
+	debugfs_create_file("kmemleak", 0644, NULL, NULL, &kmemleak_fops);
 
 	if (kmemleak_error) {
 		/*
@@ -2113,11 +1973,14 @@
 		return -ENOMEM;
 	}
 
-	mutex_lock(&scan_mutex);
-	start_scan_thread();
-	mutex_unlock(&scan_mutex);
+	if (IS_ENABLED(CONFIG_DEBUG_KMEMLEAK_AUTO_SCAN)) {
+		mutex_lock(&scan_mutex);
+		start_scan_thread();
+		mutex_unlock(&scan_mutex);
+	}
 
-	pr_info("Kernel memory leak detector initialized\n");
+	pr_info("Kernel memory leak detector initialized (mem pool available: %d)\n",
+		mem_pool_free_count);
 
 	return 0;
 }