mm: kmemleak: add rbtree and store physical address for objects allocated with PA (0c24e061) · Commits · EulixOS / Software / Kernel

mm/kmemleak.c

+91 −42

Original line number	Diff line number	Diff line
		@@ -14,14 +14,16 @@
		* 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. The object_list is the main list
		* holding the metadata (struct kmemleak_object) for the allocated memory
		* blocks. The object_tree_root is a red black tree used to look-up
		* metadata based on a pointer to the corresponding memory block. The
		* kmemleak_object structures are added to the object_list and
		* object_tree_root in the create_object() function called from the
		* kmemleak_alloc() callback and removed in delete_object() called from the
		* kmemleak_free() callback
		* 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)
		* in the create_object() function called from the kmemleak_alloc() (or
		* kmemleak_alloc_phys()) callback and removed in delete_object() called from
		* the kmemleak_free() callback
		* - kmemleak_object.lock (raw_spinlock_t): protects a kmemleak_object.
		* Accesses to the metadata (e.g. count) are protected by this lock. Note
		* that some members of this structure may be protected by other means
		@@ -195,7 +197,9 @@ 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;
		/* protecting the access to object_list and object_tree_root */
		/* search tree for object (with OBJECT_PHYS flag) boundaries */
		static struct rb_root object_phys_tree_root = RB_ROOT;
		/* protecting the access to object_list, object_tree_root (or object_phys_tree_root) */
		static DEFINE_RAW_SPINLOCK(kmemleak_lock);

		/* allocation caches for kmemleak internal data */
		@@ -287,6 +291,9 @@ static void hex_dump_object(struct seq_file *seq,
		const u8 ptr = (const u8 )object->pointer;
		size_t len;

		if (WARN_ON_ONCE(object->flags & OBJECT_PHYS))
		return;

		/* limit the number of lines to HEX_MAX_LINES */
		len = min_t(size_t, object->size, HEX_MAX_LINES * HEX_ROW_SIZE);

		@@ -380,9 +387,11 @@ static void dump_object_info(struct kmemleak_object *object)
		* beginning of the memory block are allowed. The kmemleak_lock must be held
		* when calling this function.
		*/
		static struct kmemleak_object *lookup_object(unsigned long ptr, int alias)
		static struct kmemleak_object *__lookup_object(unsigned long ptr, int alias,
		bool is_phys)
		{
		struct rb_node *rb = object_tree_root.rb_node;
		struct rb_node *rb = is_phys ? object_phys_tree_root.rb_node :
		object_tree_root.rb_node;
		unsigned long untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr);

		while (rb) {
		@@ -408,6 +417,12 @@ static struct kmemleak_object *lookup_object(unsigned long ptr, int alias)
		return NULL;
		}

		/* Look-up a kmemleak object which allocated with virtual address. */
		static struct kmemleak_object *lookup_object(unsigned long ptr, int alias)
		{
		return __lookup_object(ptr, alias, false);
		}

		/*
		* Increment the object use_count. Return 1 if successful or 0 otherwise. Note
		* that once an object's use_count reached 0, the RCU freeing was already
		@@ -517,14 +532,15 @@ static void put_object(struct kmemleak_object *object)
		/*
		* Look up an object in the object search tree and increase its use_count.
		*/
		static struct kmemleak_object *find_and_get_object(unsigned long ptr, int alias)
		static struct kmemleak_object *__find_and_get_object(unsigned long ptr, int alias,
		bool is_phys)
		{
		unsigned long flags;
		struct kmemleak_object *object;

		rcu_read_lock();
		raw_spin_lock_irqsave(&kmemleak_lock, flags);
		object = lookup_object(ptr, alias);
		object = __lookup_object(ptr, alias, is_phys);
		raw_spin_unlock_irqrestore(&kmemleak_lock, flags);

		/* check whether the object is still available */
		@@ -535,28 +551,39 @@ static struct kmemleak_object *find_and_get_object(unsigned long ptr, int alias)
		return object;
		}

		/* Look up and get an object which allocated with virtual address. */
		static struct kmemleak_object *find_and_get_object(unsigned long ptr, int alias)
		{
		return __find_and_get_object(ptr, alias, false);
		}

		/*
		* Remove an object from the object_tree_root and object_list. Must be called
		* with the kmemleak_lock held _if_ kmemleak is still enabled.
		* Remove an object from the object_tree_root (or object_phys_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);
		rb_erase(&object->rb_node, object->flags & OBJECT_PHYS ?
		&object_phys_tree_root :
		&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().
		* object_tree_root (or object_phys_tree_root) and object_list. The
		* returned object's use_count should be at least 1, as initially set
		* by create_object().
		*/
		static struct kmemleak_object *find_and_remove_object(unsigned long ptr, int alias)
		static struct kmemleak_object *find_and_remove_object(unsigned long ptr, int alias,
		bool is_phys)
		{
		unsigned long flags;
		struct kmemleak_object *object;

		raw_spin_lock_irqsave(&kmemleak_lock, flags);
		object = lookup_object(ptr, alias);
		object = __lookup_object(ptr, alias, is_phys);
		if (object)
		__remove_object(object);
		raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
		@@ -574,7 +601,8 @@ static int __save_stack_trace(unsigned long *trace)

		/*
		* Create the metadata (struct kmemleak_object) corresponding to an allocated
		* memory block and add it to the object_list and object_tree_root.
		* memory block and add it to the object_list and object_tree_root (or
		* object_phys_tree_root).
		*/
		static struct kmemleak_object *__create_object(unsigned long ptr, size_t size,
		int min_count, gfp_t gfp,
		@@ -631,9 +659,16 @@ static struct kmemleak_object *__create_object(unsigned long ptr, size_t size,
		raw_spin_lock_irqsave(&kmemleak_lock, flags);

		untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr);
		/*
		* Only update min_addr and max_addr with object
		* storing virtual address.
		*/
		if (!is_phys) {
		min_addr = min(min_addr, untagged_ptr);
		max_addr = max(max_addr, untagged_ptr + size);
		link = &object_tree_root.rb_node;
		}
		link = is_phys ? &object_phys_tree_root.rb_node :
		&object_tree_root.rb_node;
		rb_parent = NULL;
		while (*link) {
		rb_parent = *link;
		@@ -657,7 +692,8 @@ static struct kmemleak_object *__create_object(unsigned long ptr, size_t size,
		}
		}
		rb_link_node(&object->rb_node, rb_parent, link);
		rb_insert_color(&object->rb_node, &object_tree_root);
		rb_insert_color(&object->rb_node, is_phys ? &object_phys_tree_root :
		&object_tree_root);

		list_add_tail_rcu(&object->object_list, &object_list);
		out:
		@@ -707,7 +743,7 @@ static void delete_object_full(unsigned long ptr)
		{
		struct kmemleak_object *object;

		object = find_and_remove_object(ptr, 0);
		object = find_and_remove_object(ptr, 0, false);
		if (!object) {
		#ifdef DEBUG
		kmemleak_warn("Freeing unknown object at 0x%08lx\n",
		@@ -723,12 +759,12 @@ static void delete_object_full(unsigned long ptr)
		* delete it. If the memory block is partially freed, the function may create
		* additional metadata for the remaining parts of the block.
		*/
		static void delete_object_part(unsigned long ptr, size_t size)
		static void delete_object_part(unsigned long ptr, size_t size, bool is_phys)
		{
		struct kmemleak_object *object;
		unsigned long start, end;

		object = find_and_remove_object(ptr, 1);
		object = find_and_remove_object(ptr, 1, is_phys);
		if (!object) {
		#ifdef DEBUG
		kmemleak_warn("Partially freeing unknown object at 0x%08lx (size %zu)\n",
		@@ -746,10 +782,10 @@ static void delete_object_part(unsigned long ptr, size_t size)
		end = object->pointer + object->size;
		if (ptr > start)
		__create_object(start, ptr - start, object->min_count,
		GFP_KERNEL, object->flags & OBJECT_PHYS);
		GFP_KERNEL, is_phys);
		if (ptr + size < end)
		__create_object(ptr + size, end - ptr - size, object->min_count,
		GFP_KERNEL, object->flags & OBJECT_PHYS);
		GFP_KERNEL, is_phys);

		__delete_object(object);
		}
		@@ -770,11 +806,11 @@ static void paint_it(struct kmemleak_object *object, int color)
		raw_spin_unlock_irqrestore(&object->lock, flags);
		}

		static void paint_ptr(unsigned long ptr, int color)
		static void paint_ptr(unsigned long ptr, int color, bool is_phys)
		{
		struct kmemleak_object *object;

		object = find_and_get_object(ptr, 0);
		object = __find_and_get_object(ptr, 0, is_phys);
		if (!object) {
		kmemleak_warn("Trying to color unknown object at 0x%08lx as %s\n",
		ptr,
		@@ -792,16 +828,16 @@ static void paint_ptr(unsigned long ptr, int color)
		*/
		static void make_gray_object(unsigned long ptr)
		{
		paint_ptr(ptr, KMEMLEAK_GREY);
		paint_ptr(ptr, KMEMLEAK_GREY, false);
		}

		/*
		* Mark the object as black-colored so that it is ignored from scans and
		* reporting.
		*/
		static void make_black_object(unsigned long ptr)
		static void make_black_object(unsigned long ptr, bool is_phys)
		{
		paint_ptr(ptr, KMEMLEAK_BLACK);
		paint_ptr(ptr, KMEMLEAK_BLACK, is_phys);
		}

		/*
		@@ -1007,7 +1043,7 @@ void __ref kmemleak_free_part(const void *ptr, size_t size)
		pr_debug("%s(0x%p)\n", __func__, ptr);

		if (kmemleak_enabled && ptr && !IS_ERR(ptr))
		delete_object_part((unsigned long)ptr, size);
		delete_object_part((unsigned long)ptr, size, false);
		}
		EXPORT_SYMBOL_GPL(kmemleak_free_part);

		@@ -1095,7 +1131,7 @@ void __ref kmemleak_ignore(const void *ptr)
		pr_debug("%s(0x%p)\n", __func__, ptr);

		if (kmemleak_enabled && ptr && !IS_ERR(ptr))
		make_black_object((unsigned long)ptr);
		make_black_object((unsigned long)ptr, false);
		}
		EXPORT_SYMBOL(kmemleak_ignore);

		@@ -1153,7 +1189,7 @@ void __ref kmemleak_alloc_phys(phys_addr_t phys, size_t size, gfp_t gfp)
		* Create object with OBJECT_PHYS flag and
		* assume min_count 0.
		*/
		create_object_phys((unsigned long)__va(phys), size, 0, gfp);
		create_object_phys((unsigned long)phys, size, 0, gfp);
		}
		EXPORT_SYMBOL(kmemleak_alloc_phys);

		@@ -1166,8 +1202,10 @@ EXPORT_SYMBOL(kmemleak_alloc_phys);
		*/
		void __ref kmemleak_free_part_phys(phys_addr_t phys, size_t size)
		{
		pr_debug("%s(0x%pa)\n", __func__, &phys);

		if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn)
		kmemleak_free_part(__va(phys), size);
		delete_object_part((unsigned long)phys, size, true);
		}
		EXPORT_SYMBOL(kmemleak_free_part_phys);

		@@ -1178,8 +1216,10 @@ EXPORT_SYMBOL(kmemleak_free_part_phys);
		*/
		void __ref kmemleak_ignore_phys(phys_addr_t phys)
		{
		pr_debug("%s(0x%pa)\n", __func__, &phys);

		if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn)
		kmemleak_ignore(__va(phys));
		make_black_object((unsigned long)phys, true);
		}
		EXPORT_SYMBOL(kmemleak_ignore_phys);

		@@ -1190,6 +1230,9 @@ static bool update_checksum(struct kmemleak_object *object)
		{
		u32 old_csum = object->checksum;

		if (WARN_ON_ONCE(object->flags & OBJECT_PHYS))
		return false;

		kasan_disable_current();
		kcsan_disable_current();
		object->checksum = crc32(0, kasan_reset_tag((void *)object->pointer), object->size);
		@@ -1343,6 +1386,7 @@ static void scan_object(struct kmemleak_object *object)
		{
		struct kmemleak_scan_area *area;
		unsigned long flags;
		void *obj_ptr;

		/*
		* Once the object->lock is acquired, the corresponding memory block
		@@ -1354,10 +1398,15 @@ static void scan_object(struct kmemleak_object *object)
		if (!(object->flags & OBJECT_ALLOCATED))
		/* already freed object */
		goto out;

		obj_ptr = object->flags & OBJECT_PHYS ?
		__va((phys_addr_t)object->pointer) :
		(void *)object->pointer;

		if (hlist_empty(&object->area_list) \|\|
		object->flags & OBJECT_FULL_SCAN) {
		void start = (void )object->pointer;
		void end = (void )(object->pointer + object->size);
		void *start = obj_ptr;
		void *end = obj_ptr + object->size;
		void *next;

		do {