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-rw-r--r--mm/kmemleak.c140
1 files changed, 79 insertions, 61 deletions
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 31f01c5011e5..91d67eaee050 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -192,15 +192,15 @@ static struct kmem_cache *object_cache;
static struct kmem_cache *scan_area_cache;
/* set if tracing memory operations is enabled */
-static atomic_t kmemleak_enabled = ATOMIC_INIT(0);
+static int kmemleak_enabled;
/* set in the late_initcall if there were no errors */
-static atomic_t kmemleak_initialized = ATOMIC_INIT(0);
+static int kmemleak_initialized;
/* enables or disables early logging of the memory operations */
-static atomic_t kmemleak_early_log = ATOMIC_INIT(1);
+static int kmemleak_early_log = 1;
/* set if a kmemleak warning was issued */
-static atomic_t kmemleak_warning = ATOMIC_INIT(0);
+static int kmemleak_warning;
/* set if a fatal kmemleak error has occurred */
-static atomic_t kmemleak_error = ATOMIC_INIT(0);
+static int kmemleak_error;
/* minimum and maximum address that may be valid pointers */
static unsigned long min_addr = ULONG_MAX;
@@ -218,7 +218,8 @@ static int kmemleak_stack_scan = 1;
static DEFINE_MUTEX(scan_mutex);
/* setting kmemleak=on, will set this var, skipping the disable */
static int kmemleak_skip_disable;
-
+/* If there are leaks that can be reported */
+static bool kmemleak_found_leaks;
/*
* Early object allocation/freeing logging. Kmemleak is initialized after the
@@ -267,7 +268,7 @@ static void kmemleak_disable(void);
#define kmemleak_warn(x...) do { \
pr_warning(x); \
dump_stack(); \
- atomic_set(&kmemleak_warning, 1); \
+ kmemleak_warning = 1; \
} while (0)
/*
@@ -805,7 +806,7 @@ static void __init log_early(int op_type, const void *ptr, size_t size,
unsigned long flags;
struct early_log *log;
- if (atomic_read(&kmemleak_error)) {
+ if (kmemleak_error) {
/* kmemleak stopped recording, just count the requests */
crt_early_log++;
return;
@@ -840,7 +841,7 @@ static void early_alloc(struct early_log *log)
unsigned long flags;
int i;
- if (!atomic_read(&kmemleak_enabled) || !log->ptr || IS_ERR(log->ptr))
+ if (!kmemleak_enabled || !log->ptr || IS_ERR(log->ptr))
return;
/*
@@ -893,9 +894,9 @@ void __ref kmemleak_alloc(const void *ptr, size_t size, int min_count,
{
pr_debug("%s(0x%p, %zu, %d)\n", __func__, ptr, size, min_count);
- if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+ if (kmemleak_enabled && ptr && !IS_ERR(ptr))
create_object((unsigned long)ptr, size, min_count, gfp);
- else if (atomic_read(&kmemleak_early_log))
+ else if (kmemleak_early_log)
log_early(KMEMLEAK_ALLOC, ptr, size, min_count);
}
EXPORT_SYMBOL_GPL(kmemleak_alloc);
@@ -919,11 +920,11 @@ void __ref kmemleak_alloc_percpu(const void __percpu *ptr, size_t size)
* Percpu allocations are only scanned and not reported as leaks
* (min_count is set to 0).
*/
- if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+ if (kmemleak_enabled && ptr && !IS_ERR(ptr))
for_each_possible_cpu(cpu)
create_object((unsigned long)per_cpu_ptr(ptr, cpu),
size, 0, GFP_KERNEL);
- else if (atomic_read(&kmemleak_early_log))
+ else if (kmemleak_early_log)
log_early(KMEMLEAK_ALLOC_PERCPU, ptr, size, 0);
}
EXPORT_SYMBOL_GPL(kmemleak_alloc_percpu);
@@ -939,9 +940,9 @@ void __ref kmemleak_free(const void *ptr)
{
pr_debug("%s(0x%p)\n", __func__, ptr);
- if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+ if (kmemleak_enabled && ptr && !IS_ERR(ptr))
delete_object_full((unsigned long)ptr);
- else if (atomic_read(&kmemleak_early_log))
+ else if (kmemleak_early_log)
log_early(KMEMLEAK_FREE, ptr, 0, 0);
}
EXPORT_SYMBOL_GPL(kmemleak_free);
@@ -959,9 +960,9 @@ void __ref kmemleak_free_part(const void *ptr, size_t size)
{
pr_debug("%s(0x%p)\n", __func__, ptr);
- if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+ if (kmemleak_enabled && ptr && !IS_ERR(ptr))
delete_object_part((unsigned long)ptr, size);
- else if (atomic_read(&kmemleak_early_log))
+ else if (kmemleak_early_log)
log_early(KMEMLEAK_FREE_PART, ptr, size, 0);
}
EXPORT_SYMBOL_GPL(kmemleak_free_part);
@@ -979,11 +980,11 @@ void __ref kmemleak_free_percpu(const void __percpu *ptr)
pr_debug("%s(0x%p)\n", __func__, ptr);
- if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+ if (kmemleak_enabled && ptr && !IS_ERR(ptr))
for_each_possible_cpu(cpu)
delete_object_full((unsigned long)per_cpu_ptr(ptr,
cpu));
- else if (atomic_read(&kmemleak_early_log))
+ else if (kmemleak_early_log)
log_early(KMEMLEAK_FREE_PERCPU, ptr, 0, 0);
}
EXPORT_SYMBOL_GPL(kmemleak_free_percpu);
@@ -999,9 +1000,9 @@ void __ref kmemleak_not_leak(const void *ptr)
{
pr_debug("%s(0x%p)\n", __func__, ptr);
- if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+ if (kmemleak_enabled && ptr && !IS_ERR(ptr))
make_gray_object((unsigned long)ptr);
- else if (atomic_read(&kmemleak_early_log))
+ else if (kmemleak_early_log)
log_early(KMEMLEAK_NOT_LEAK, ptr, 0, 0);
}
EXPORT_SYMBOL(kmemleak_not_leak);
@@ -1019,9 +1020,9 @@ void __ref kmemleak_ignore(const void *ptr)
{
pr_debug("%s(0x%p)\n", __func__, ptr);
- if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+ if (kmemleak_enabled && ptr && !IS_ERR(ptr))
make_black_object((unsigned long)ptr);
- else if (atomic_read(&kmemleak_early_log))
+ else if (kmemleak_early_log)
log_early(KMEMLEAK_IGNORE, ptr, 0, 0);
}
EXPORT_SYMBOL(kmemleak_ignore);
@@ -1041,9 +1042,9 @@ void __ref kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp)
{
pr_debug("%s(0x%p)\n", __func__, ptr);
- if (atomic_read(&kmemleak_enabled) && ptr && size && !IS_ERR(ptr))
+ if (kmemleak_enabled && ptr && size && !IS_ERR(ptr))
add_scan_area((unsigned long)ptr, size, gfp);
- else if (atomic_read(&kmemleak_early_log))
+ else if (kmemleak_early_log)
log_early(KMEMLEAK_SCAN_AREA, ptr, size, 0);
}
EXPORT_SYMBOL(kmemleak_scan_area);
@@ -1061,9 +1062,9 @@ void __ref kmemleak_no_scan(const void *ptr)
{
pr_debug("%s(0x%p)\n", __func__, ptr);
- if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+ if (kmemleak_enabled && ptr && !IS_ERR(ptr))
object_no_scan((unsigned long)ptr);
- else if (atomic_read(&kmemleak_early_log))
+ else if (kmemleak_early_log)
log_early(KMEMLEAK_NO_SCAN, ptr, 0, 0);
}
EXPORT_SYMBOL(kmemleak_no_scan);
@@ -1088,7 +1089,7 @@ static bool update_checksum(struct kmemleak_object *object)
*/
static int scan_should_stop(void)
{
- if (!atomic_read(&kmemleak_enabled))
+ if (!kmemleak_enabled)
return 1;
/*
@@ -1382,9 +1383,12 @@ static void kmemleak_scan(void)
}
rcu_read_unlock();
- if (new_leaks)
+ if (new_leaks) {
+ kmemleak_found_leaks = true;
+
pr_info("%d new suspected memory leaks (see "
"/sys/kernel/debug/kmemleak)\n", new_leaks);
+ }
}
@@ -1545,11 +1549,6 @@ static int kmemleak_open(struct inode *inode, struct file *file)
return seq_open(file, &kmemleak_seq_ops);
}
-static int kmemleak_release(struct inode *inode, struct file *file)
-{
- return seq_release(inode, file);
-}
-
static int dump_str_object_info(const char *str)
{
unsigned long flags;
@@ -1592,8 +1591,12 @@ static void kmemleak_clear(void)
spin_unlock_irqrestore(&object->lock, flags);
}
rcu_read_unlock();
+
+ kmemleak_found_leaks = false;
}
+static void __kmemleak_do_cleanup(void);
+
/*
* File write operation to configure kmemleak at run-time. The following
* commands can be written to the /sys/kernel/debug/kmemleak file:
@@ -1606,7 +1609,8 @@ static void kmemleak_clear(void)
* disable it)
* scan - trigger a memory scan
* clear - mark all current reported unreferenced kmemleak objects as
- * grey to ignore printing them
+ * grey to ignore printing them, or free all kmemleak objects
+ * if kmemleak has been disabled.
* dump=... - dump information about the object found at the given address
*/
static ssize_t kmemleak_write(struct file *file, const char __user *user_buf,
@@ -1616,9 +1620,6 @@ static ssize_t kmemleak_write(struct file *file, const char __user *user_buf,
int buf_size;
int ret;
- if (!atomic_read(&kmemleak_enabled))
- return -EBUSY;
-
buf_size = min(size, (sizeof(buf) - 1));
if (strncpy_from_user(buf, user_buf, buf_size) < 0)
return -EFAULT;
@@ -1628,6 +1629,19 @@ static ssize_t kmemleak_write(struct file *file, const char __user *user_buf,
if (ret < 0)
return ret;
+ if (strncmp(buf, "clear", 5) == 0) {
+ if (kmemleak_enabled)
+ kmemleak_clear();
+ else
+ __kmemleak_do_cleanup();
+ goto out;
+ }
+
+ if (!kmemleak_enabled) {
+ ret = -EBUSY;
+ goto out;
+ }
+
if (strncmp(buf, "off", 3) == 0)
kmemleak_disable();
else if (strncmp(buf, "stack=on", 8) == 0)
@@ -1651,8 +1665,6 @@ static ssize_t kmemleak_write(struct file *file, const char __user *user_buf,
}
} else if (strncmp(buf, "scan", 4) == 0)
kmemleak_scan();
- else if (strncmp(buf, "clear", 5) == 0)
- kmemleak_clear();
else if (strncmp(buf, "dump=", 5) == 0)
ret = dump_str_object_info(buf + 5);
else
@@ -1674,9 +1686,19 @@ static const struct file_operations kmemleak_fops = {
.read = seq_read,
.write = kmemleak_write,
.llseek = seq_lseek,
- .release = kmemleak_release,
+ .release = seq_release,
};
+static void __kmemleak_do_cleanup(void)
+{
+ struct kmemleak_object *object;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(object, &object_list, object_list)
+ delete_object_full(object->pointer);
+ rcu_read_unlock();
+}
+
/*
* Stop the memory scanning thread and free the kmemleak internal objects if
* no previous scan thread (otherwise, kmemleak may still have some useful
@@ -1684,18 +1706,14 @@ static const struct file_operations kmemleak_fops = {
*/
static void kmemleak_do_cleanup(struct work_struct *work)
{
- struct kmemleak_object *object;
- bool cleanup = scan_thread == NULL;
-
mutex_lock(&scan_mutex);
stop_scan_thread();
- if (cleanup) {
- rcu_read_lock();
- list_for_each_entry_rcu(object, &object_list, object_list)
- delete_object_full(object->pointer);
- rcu_read_unlock();
- }
+ if (!kmemleak_found_leaks)
+ __kmemleak_do_cleanup();
+ else
+ pr_info("Kmemleak disabled without freeing internal data. "
+ "Reclaim the memory with \"echo clear > /sys/kernel/debug/kmemleak\"\n");
mutex_unlock(&scan_mutex);
}
@@ -1708,14 +1726,14 @@ static DECLARE_WORK(cleanup_work, kmemleak_do_cleanup);
static void kmemleak_disable(void)
{
/* atomically check whether it was already invoked */
- if (atomic_cmpxchg(&kmemleak_error, 0, 1))
+ if (cmpxchg(&kmemleak_error, 0, 1))
return;
/* stop any memory operation tracing */
- atomic_set(&kmemleak_enabled, 0);
+ kmemleak_enabled = 0;
/* check whether it is too early for a kernel thread */
- if (atomic_read(&kmemleak_initialized))
+ if (kmemleak_initialized)
schedule_work(&cleanup_work);
pr_info("Kernel memory leak detector disabled\n");
@@ -1757,9 +1775,10 @@ void __init kmemleak_init(void)
int i;
unsigned long flags;
+ kmemleak_early_log = 0;
+
#ifdef CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF
if (!kmemleak_skip_disable) {
- atomic_set(&kmemleak_early_log, 0);
kmemleak_disable();
return;
}
@@ -1777,12 +1796,11 @@ void __init kmemleak_init(void)
/* the kernel is still in UP mode, so disabling the IRQs is enough */
local_irq_save(flags);
- atomic_set(&kmemleak_early_log, 0);
- if (atomic_read(&kmemleak_error)) {
+ if (kmemleak_error) {
local_irq_restore(flags);
return;
} else
- atomic_set(&kmemleak_enabled, 1);
+ kmemleak_enabled = 1;
local_irq_restore(flags);
/*
@@ -1826,9 +1844,9 @@ void __init kmemleak_init(void)
log->op_type);
}
- if (atomic_read(&kmemleak_warning)) {
+ if (kmemleak_warning) {
print_log_trace(log);
- atomic_set(&kmemleak_warning, 0);
+ kmemleak_warning = 0;
}
}
}
@@ -1840,9 +1858,9 @@ static int __init kmemleak_late_init(void)
{
struct dentry *dentry;
- atomic_set(&kmemleak_initialized, 1);
+ kmemleak_initialized = 1;
- if (atomic_read(&kmemleak_error)) {
+ if (kmemleak_error) {
/*
* Some error occurred and kmemleak was disabled. There is a
* small chance that kmemleak_disable() was called immediately