diff options
Diffstat (limited to 'mm/kmemleak.c')
-rw-r--r-- | mm/kmemleak.c | 222 |
1 files changed, 120 insertions, 102 deletions
diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 1eacca03bedd..6a540c2b27c5 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -14,17 +14,15 @@ * The following locks and mutexes are used by kmemleak: * * - 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) - * 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 + * del_state modifications and accesses to the object trees + * (object_tree_root, object_phys_tree_root, object_percpu_tree_root). The + * object_list is the main list holding the metadata (struct + * kmemleak_object) for the allocated memory blocks. The object trees are + * red black trees 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 the object tree root in the create_object() function + * called from the kmemleak_alloc{,_phys,_percpu}() callback and removed in + * delete_object() called from the kmemleak_free{,_phys,_percpu}() 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 @@ -178,6 +176,8 @@ struct kmemleak_object { #define OBJECT_FULL_SCAN (1 << 3) /* flag set for object allocated with physical address */ #define OBJECT_PHYS (1 << 4) +/* flag set for per-CPU pointers */ +#define OBJECT_PERCPU (1 << 5) /* set when __remove_object() called */ #define DELSTATE_REMOVED (1 << 0) @@ -206,6 +206,8 @@ static LIST_HEAD(mem_pool_free_list); static struct rb_root object_tree_root = RB_ROOT; /* search tree for object (with OBJECT_PHYS flag) boundaries */ static struct rb_root object_phys_tree_root = RB_ROOT; +/* search tree for object (with OBJECT_PERCPU flag) boundaries */ +static struct rb_root object_percpu_tree_root = RB_ROOT; /* protecting the access to object_list, object_tree_root (or object_phys_tree_root) */ static DEFINE_RAW_SPINLOCK(kmemleak_lock); @@ -298,7 +300,7 @@ 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)) + if (WARN_ON_ONCE(object->flags & (OBJECT_PHYS | OBJECT_PERCPU))) return; /* limit the number of lines to HEX_MAX_LINES */ @@ -355,16 +357,14 @@ static void print_unreferenced(struct seq_file *seq, int i; unsigned long *entries; unsigned int nr_entries; - unsigned int msecs_age = jiffies_to_msecs(jiffies - object->jiffies); nr_entries = stack_depot_fetch(object->trace_handle, &entries); warn_or_seq_printf(seq, "unreferenced object 0x%08lx (size %zu):\n", object->pointer, object->size); - 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); + warn_or_seq_printf(seq, " comm \"%s\", pid %d, jiffies %lu\n", + object->comm, object->pid, object->jiffies); hex_dump_object(seq, object); - warn_or_seq_printf(seq, " backtrace:\n"); + warn_or_seq_printf(seq, " backtrace (crc %x):\n", object->checksum); for (i = 0; i < nr_entries; i++) { void *ptr = (void *)entries[i]; @@ -392,6 +392,15 @@ static void dump_object_info(struct kmemleak_object *object) stack_depot_print(object->trace_handle); } +static struct rb_root *object_tree(unsigned long objflags) +{ + if (objflags & OBJECT_PHYS) + return &object_phys_tree_root; + if (objflags & OBJECT_PERCPU) + return &object_percpu_tree_root; + return &object_tree_root; +} + /* * Look-up a memory block metadata (kmemleak_object) in the object search * tree based on a pointer value. If alias is 0, only values pointing to the @@ -399,10 +408,9 @@ static void dump_object_info(struct kmemleak_object *object) * when calling this function. */ static struct kmemleak_object *__lookup_object(unsigned long ptr, int alias, - bool is_phys) + unsigned int objflags) { - struct rb_node *rb = is_phys ? object_phys_tree_root.rb_node : - object_tree_root.rb_node; + struct rb_node *rb = object_tree(objflags)->rb_node; unsigned long untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr); while (rb) { @@ -431,7 +439,7 @@ static struct kmemleak_object *__lookup_object(unsigned long ptr, int alias, /* 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); + return __lookup_object(ptr, alias, 0); } /* @@ -544,14 +552,14 @@ 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, - bool is_phys) + unsigned int objflags) { unsigned long flags; struct kmemleak_object *object; rcu_read_lock(); raw_spin_lock_irqsave(&kmemleak_lock, flags); - object = __lookup_object(ptr, alias, is_phys); + object = __lookup_object(ptr, alias, objflags); raw_spin_unlock_irqrestore(&kmemleak_lock, flags); /* check whether the object is still available */ @@ -565,19 +573,16 @@ static struct kmemleak_object *__find_and_get_object(unsigned long ptr, int alia /* 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); + return __find_and_get_object(ptr, alias, 0); } /* - * 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. + * Remove an object from its object tree 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->flags & OBJECT_PHYS ? - &object_phys_tree_root : - &object_tree_root); + rb_erase(&object->rb_node, object_tree(object->flags)); if (!(object->del_state & DELSTATE_NO_DELETE)) list_del_rcu(&object->object_list); object->del_state |= DELSTATE_REMOVED; @@ -585,11 +590,11 @@ static void __remove_object(struct kmemleak_object *object) static struct kmemleak_object *__find_and_remove_object(unsigned long ptr, int alias, - bool is_phys) + unsigned int objflags) { struct kmemleak_object *object; - object = __lookup_object(ptr, alias, is_phys); + object = __lookup_object(ptr, alias, objflags); if (object) __remove_object(object); @@ -597,19 +602,18 @@ static struct kmemleak_object *__find_and_remove_object(unsigned long ptr, } /* - * Look up an object in the object search tree and remove it from both - * 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(). + * 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(). */ static struct kmemleak_object *find_and_remove_object(unsigned long ptr, int alias, - bool is_phys) + unsigned int objflags) { unsigned long flags; struct kmemleak_object *object; raw_spin_lock_irqsave(&kmemleak_lock, flags); - object = __find_and_remove_object(ptr, alias, is_phys); + object = __find_and_remove_object(ptr, alias, objflags); raw_spin_unlock_irqrestore(&kmemleak_lock, flags); return object; @@ -642,32 +646,16 @@ static struct kmemleak_object *__alloc_object(gfp_t gfp) if (!object) { pr_warn("Cannot allocate a kmemleak_object structure\n"); kmemleak_disable(); + return NULL; } - return object; -} - -static int __link_object(struct kmemleak_object *object, unsigned long ptr, - size_t size, int min_count, bool is_phys) -{ - - struct kmemleak_object *parent; - struct rb_node **link, *rb_parent; - unsigned long untagged_ptr; - unsigned long untagged_objp; - INIT_LIST_HEAD(&object->object_list); INIT_LIST_HEAD(&object->gray_list); INIT_HLIST_HEAD(&object->area_list); raw_spin_lock_init(&object->lock); atomic_set(&object->use_count, 1); - object->flags = OBJECT_ALLOCATED | (is_phys ? OBJECT_PHYS : 0); - object->pointer = ptr; - object->size = kfence_ksize((void *)ptr) ?: size; object->excess_ref = 0; - object->min_count = min_count; object->count = 0; /* white color initially */ - object->jiffies = jiffies; object->checksum = 0; object->del_state = 0; @@ -692,17 +680,34 @@ static int __link_object(struct kmemleak_object *object, unsigned long ptr, /* kernel backtrace */ object->trace_handle = set_track_prepare(); + return object; +} + +static int __link_object(struct kmemleak_object *object, unsigned long ptr, + size_t size, int min_count, unsigned int objflags) +{ + + struct kmemleak_object *parent; + struct rb_node **link, *rb_parent; + unsigned long untagged_ptr; + unsigned long untagged_objp; + + object->flags = OBJECT_ALLOCATED | objflags; + object->pointer = ptr; + object->size = kfence_ksize((void *)ptr) ?: size; + object->min_count = min_count; + object->jiffies = jiffies; + untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr); /* * Only update min_addr and max_addr with object * storing virtual address. */ - if (!is_phys) { + if (!(objflags & (OBJECT_PHYS | OBJECT_PERCPU))) { min_addr = min(min_addr, untagged_ptr); max_addr = max(max_addr, untagged_ptr + size); } - link = is_phys ? &object_phys_tree_root.rb_node : - &object_tree_root.rb_node; + link = &object_tree(objflags)->rb_node; rb_parent = NULL; while (*link) { rb_parent = *link; @@ -724,8 +729,7 @@ static int __link_object(struct kmemleak_object *object, unsigned long ptr, } } rb_link_node(&object->rb_node, rb_parent, link); - rb_insert_color(&object->rb_node, is_phys ? &object_phys_tree_root : - &object_tree_root); + rb_insert_color(&object->rb_node, object_tree(objflags)); list_add_tail_rcu(&object->object_list, &object_list); return 0; @@ -733,11 +737,10 @@ static int __link_object(struct kmemleak_object *object, unsigned long ptr, /* * Create the metadata (struct kmemleak_object) corresponding to an allocated - * memory block and add it to the object_list and object_tree_root (or - * object_phys_tree_root). + * memory block and add it to the object_list and object tree. */ static void __create_object(unsigned long ptr, size_t size, - int min_count, gfp_t gfp, bool is_phys) + int min_count, gfp_t gfp, unsigned int objflags) { struct kmemleak_object *object; unsigned long flags; @@ -748,7 +751,7 @@ static void __create_object(unsigned long ptr, size_t size, return; raw_spin_lock_irqsave(&kmemleak_lock, flags); - ret = __link_object(object, ptr, size, min_count, is_phys); + ret = __link_object(object, ptr, size, min_count, objflags); raw_spin_unlock_irqrestore(&kmemleak_lock, flags); if (ret) mem_pool_free(object); @@ -758,14 +761,21 @@ static void __create_object(unsigned long ptr, size_t size, static void create_object(unsigned long ptr, size_t size, int min_count, gfp_t gfp) { - __create_object(ptr, size, min_count, gfp, false); + __create_object(ptr, size, min_count, gfp, 0); } /* Create kmemleak object which allocated with physical address. */ static void create_object_phys(unsigned long ptr, size_t size, int min_count, gfp_t gfp) { - __create_object(ptr, size, min_count, gfp, true); + __create_object(ptr, size, min_count, gfp, OBJECT_PHYS); +} + +/* Create kmemleak object corresponding to a per-CPU allocation. */ +static void create_object_percpu(unsigned long ptr, size_t size, + int min_count, gfp_t gfp) +{ + __create_object(ptr, size, min_count, gfp, OBJECT_PERCPU); } /* @@ -792,11 +802,11 @@ static void __delete_object(struct kmemleak_object *object) * Look up the metadata (struct kmemleak_object) corresponding to ptr and * delete it. */ -static void delete_object_full(unsigned long ptr) +static void delete_object_full(unsigned long ptr, unsigned int objflags) { struct kmemleak_object *object; - object = find_and_remove_object(ptr, 0, false); + object = find_and_remove_object(ptr, 0, objflags); if (!object) { #ifdef DEBUG kmemleak_warn("Freeing unknown object at 0x%08lx\n", @@ -812,7 +822,8 @@ 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, bool is_phys) +static void delete_object_part(unsigned long ptr, size_t size, + unsigned int objflags) { struct kmemleak_object *object, *object_l, *object_r; unsigned long start, end, flags; @@ -826,7 +837,7 @@ static void delete_object_part(unsigned long ptr, size_t size, bool is_phys) goto out; raw_spin_lock_irqsave(&kmemleak_lock, flags); - object = __find_and_remove_object(ptr, 1, is_phys); + object = __find_and_remove_object(ptr, 1, objflags); if (!object) { #ifdef DEBUG kmemleak_warn("Partially freeing unknown object at 0x%08lx (size %zu)\n", @@ -844,11 +855,11 @@ static void delete_object_part(unsigned long ptr, size_t size, bool is_phys) end = object->pointer + object->size; if ((ptr > start) && !__link_object(object_l, start, ptr - start, - object->min_count, is_phys)) + object->min_count, objflags)) object_l = NULL; if ((ptr + size < end) && !__link_object(object_r, ptr + size, end - ptr - size, - object->min_count, is_phys)) + object->min_count, objflags)) object_r = NULL; unlock: @@ -879,11 +890,11 @@ 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, bool is_phys) +static void paint_ptr(unsigned long ptr, int color, unsigned int objflags) { struct kmemleak_object *object; - object = __find_and_get_object(ptr, 0, is_phys); + object = __find_and_get_object(ptr, 0, objflags); if (!object) { kmemleak_warn("Trying to color unknown object at 0x%08lx as %s\n", ptr, @@ -901,16 +912,16 @@ static void paint_ptr(unsigned long ptr, int color, bool is_phys) */ static void make_gray_object(unsigned long ptr) { - paint_ptr(ptr, KMEMLEAK_GREY, false); + paint_ptr(ptr, KMEMLEAK_GREY, 0); } /* * Mark the object as black-colored so that it is ignored from scans and * reporting. */ -static void make_black_object(unsigned long ptr, bool is_phys) +static void make_black_object(unsigned long ptr, unsigned int objflags) { - paint_ptr(ptr, KMEMLEAK_BLACK, is_phys); + paint_ptr(ptr, KMEMLEAK_BLACK, objflags); } /* @@ -1046,8 +1057,6 @@ EXPORT_SYMBOL_GPL(kmemleak_alloc); void __ref kmemleak_alloc_percpu(const void __percpu *ptr, size_t size, gfp_t gfp) { - unsigned int cpu; - pr_debug("%s(0x%px, %zu)\n", __func__, ptr, size); /* @@ -1055,9 +1064,7 @@ void __ref kmemleak_alloc_percpu(const void __percpu *ptr, size_t size, * (min_count is set to 0). */ if (kmemleak_enabled && ptr && !IS_ERR(ptr)) - for_each_possible_cpu(cpu) - create_object((unsigned long)per_cpu_ptr(ptr, cpu), - size, 0, gfp); + create_object_percpu((unsigned long)ptr, size, 0, gfp); } EXPORT_SYMBOL_GPL(kmemleak_alloc_percpu); @@ -1098,7 +1105,7 @@ void __ref kmemleak_free(const void *ptr) pr_debug("%s(0x%px)\n", __func__, ptr); if (kmemleak_free_enabled && ptr && !IS_ERR(ptr)) - delete_object_full((unsigned long)ptr); + delete_object_full((unsigned long)ptr, 0); } EXPORT_SYMBOL_GPL(kmemleak_free); @@ -1116,7 +1123,7 @@ void __ref kmemleak_free_part(const void *ptr, size_t size) pr_debug("%s(0x%px)\n", __func__, ptr); if (kmemleak_enabled && ptr && !IS_ERR(ptr)) - delete_object_part((unsigned long)ptr, size, false); + delete_object_part((unsigned long)ptr, size, 0); } EXPORT_SYMBOL_GPL(kmemleak_free_part); @@ -1129,14 +1136,10 @@ EXPORT_SYMBOL_GPL(kmemleak_free_part); */ void __ref kmemleak_free_percpu(const void __percpu *ptr) { - unsigned int cpu; - pr_debug("%s(0x%px)\n", __func__, ptr); if (kmemleak_free_enabled && ptr && !IS_ERR(ptr)) - for_each_possible_cpu(cpu) - delete_object_full((unsigned long)per_cpu_ptr(ptr, - cpu)); + delete_object_full((unsigned long)ptr, OBJECT_PERCPU); } EXPORT_SYMBOL_GPL(kmemleak_free_percpu); @@ -1150,6 +1153,7 @@ EXPORT_SYMBOL_GPL(kmemleak_free_percpu); void __ref kmemleak_update_trace(const void *ptr) { struct kmemleak_object *object; + depot_stack_handle_t trace_handle; unsigned long flags; pr_debug("%s(0x%px)\n", __func__, ptr); @@ -1166,8 +1170,9 @@ void __ref kmemleak_update_trace(const void *ptr) return; } + trace_handle = set_track_prepare(); raw_spin_lock_irqsave(&object->lock, flags); - object->trace_handle = set_track_prepare(); + object->trace_handle = trace_handle; raw_spin_unlock_irqrestore(&object->lock, flags); put_object(object); @@ -1204,7 +1209,7 @@ void __ref kmemleak_ignore(const void *ptr) pr_debug("%s(0x%px)\n", __func__, ptr); if (kmemleak_enabled && ptr && !IS_ERR(ptr)) - make_black_object((unsigned long)ptr, false); + make_black_object((unsigned long)ptr, 0); } EXPORT_SYMBOL(kmemleak_ignore); @@ -1278,7 +1283,7 @@ void __ref kmemleak_free_part_phys(phys_addr_t phys, size_t size) pr_debug("%s(0x%px)\n", __func__, &phys); if (kmemleak_enabled) - delete_object_part((unsigned long)phys, size, true); + delete_object_part((unsigned long)phys, size, OBJECT_PHYS); } EXPORT_SYMBOL(kmemleak_free_part_phys); @@ -1292,7 +1297,7 @@ void __ref kmemleak_ignore_phys(phys_addr_t phys) pr_debug("%s(0x%px)\n", __func__, &phys); if (kmemleak_enabled) - make_black_object((unsigned long)phys, true); + make_black_object((unsigned long)phys, OBJECT_PHYS); } EXPORT_SYMBOL(kmemleak_ignore_phys); @@ -1303,7 +1308,7 @@ static bool update_checksum(struct kmemleak_object *object) { u32 old_csum = object->checksum; - if (WARN_ON_ONCE(object->flags & OBJECT_PHYS)) + if (WARN_ON_ONCE(object->flags & (OBJECT_PHYS | OBJECT_PERCPU))) return false; kasan_disable_current(); @@ -1459,7 +1464,6 @@ 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 @@ -1472,14 +1476,27 @@ static void scan_object(struct kmemleak_object *object) /* already freed object */ goto out; - obj_ptr = object->flags & OBJECT_PHYS ? - __va((phys_addr_t)object->pointer) : - (void *)object->pointer; + if (object->flags & OBJECT_PERCPU) { + unsigned int cpu; - if (hlist_empty(&object->area_list) || + for_each_possible_cpu(cpu) { + void *start = per_cpu_ptr((void __percpu *)object->pointer, cpu); + void *end = start + object->size; + + scan_block(start, end, object); + + raw_spin_unlock_irqrestore(&object->lock, flags); + cond_resched(); + raw_spin_lock_irqsave(&object->lock, flags); + if (!(object->flags & OBJECT_ALLOCATED)) + break; + } + } else if (hlist_empty(&object->area_list) || object->flags & OBJECT_FULL_SCAN) { - void *start = obj_ptr; - void *end = obj_ptr + object->size; + void *start = object->flags & OBJECT_PHYS ? + __va((phys_addr_t)object->pointer) : + (void *)object->pointer; + void *end = start + object->size; void *next; do { @@ -1494,11 +1511,12 @@ static void scan_object(struct kmemleak_object *object) cond_resched(); raw_spin_lock_irqsave(&object->lock, flags); } while (object->flags & OBJECT_ALLOCATED); - } else + } else { hlist_for_each_entry(area, &object->area_list, node) scan_block((void *)area->start, (void *)(area->start + area->size), object); + } out: raw_spin_unlock_irqrestore(&object->lock, flags); } |