#include <linux/stacktrace.h>
#include <linux/debug_locks.h>
#include <linux/irqflags.h>
+#include <linux/utsname.h>
#include <asm/sections.h>
* unique.
*/
#define iterate_chain_key(key1, key2) \
- (((key1) << MAX_LOCKDEP_KEYS_BITS/2) ^ \
- ((key1) >> (64-MAX_LOCKDEP_KEYS_BITS/2)) ^ \
+ (((key1) << MAX_LOCKDEP_KEYS_BITS) ^ \
+ ((key1) >> (64-MAX_LOCKDEP_KEYS_BITS)) ^ \
(key2))
void lockdep_off(void)
*/
static int class_filter(struct lock_class *class)
{
+#if 0
+ /* Example */
if (class->name_version == 1 &&
- !strcmp(class->name, "&rl->lock"))
+ !strcmp(class->name, "lockname"))
return 1;
if (class->name_version == 1 &&
- !strcmp(class->name, "&ni->mrec_lock"))
+ !strcmp(class->name, "&struct->lockfield"))
return 1;
- if (class->name_version == 1 &&
- !strcmp(class->name, "mft_ni_runlist_lock"))
- return 1;
- if (class->name_version == 1 &&
- !strcmp(class->name, "mft_ni_mrec_lock"))
- return 1;
- if (class->name_version == 1 &&
- !strcmp(class->name, "&vol->lcnbmp_lock"))
- return 1;
- return 0;
+#endif
+ /* Allow everything else. 0 would be filter everything else */
+ return 1;
}
#endif
trace->max_entries = MAX_STACK_TRACE_ENTRIES - nr_stack_trace_entries;
trace->entries = stack_trace + nr_stack_trace_entries;
- save_stack_trace(trace, NULL, 0, 3);
+ trace->skip = 3;
+ trace->all_contexts = 0;
+
+ /* Make sure to not recurse in case the the unwinder needs to tak
+e locks. */
+ lockdep_off();
+ save_stack_trace(trace, NULL);
+ lockdep_on();
trace->max_entries = trace->nr_entries;
print_lock(curr->held_locks + i);
}
}
-/*
- * Helper to print a nice hierarchy of lock dependencies:
- */
-static void print_spaces(int nr)
-{
- int i;
-
- for (i = 0; i < nr; i++)
- printk(" ");
-}
static void print_lock_class_header(struct lock_class *class, int depth)
{
int bit;
- print_spaces(depth);
- printk("->");
+ printk("%*s->", depth, "");
print_lock_name(class);
printk(" ops: %lu", class->ops);
printk(" {\n");
if (class->usage_mask & (1 << bit)) {
int len = depth;
- print_spaces(depth);
- len += printk(" %s", usage_str[bit]);
+ len += printk("%*s %s", depth, "", usage_str[bit]);
len += printk(" at:\n");
print_stack_trace(class->usage_traces + bit, len);
}
}
- print_spaces(depth);
- printk(" }\n");
+ printk("%*s }\n", depth, "");
- print_spaces(depth);
- printk(" ... key at: ");
+ printk("%*s ... key at: ",depth,"");
print_ip_sym((unsigned long)class->key);
}
DEBUG_LOCKS_WARN_ON(!entry->class);
print_lock_dependencies(entry->class, depth + 1);
- print_spaces(depth);
- printk(" ... acquired at:\n");
+ printk("%*s ... acquired at:\n",depth,"");
print_stack_trace(&entry->trace, 2);
printk("\n");
}
return 0;
}
+static void print_kernel_version(void)
+{
+ printk("%s %.*s\n", init_utsname()->release,
+ (int)strcspn(init_utsname()->version, " "),
+ init_utsname()->version);
+}
+
/*
* When a circular dependency is detected, print the
* header first:
printk("\n=======================================================\n");
printk( "[ INFO: possible circular locking dependency detected ]\n");
+ print_kernel_version();
printk( "-------------------------------------------------------\n");
printk("%s/%d is trying to acquire lock:\n",
curr->comm, curr->pid);
return 0;
}
+#define RECURSION_LIMIT 40
+
static int noinline print_infinite_recursion_bug(void)
{
__raw_spin_unlock(&hash_lock);
debug_atomic_inc(&nr_cyclic_check_recursions);
if (depth > max_recursion_depth)
max_recursion_depth = depth;
- if (depth >= 20)
+ if (depth >= RECURSION_LIMIT)
return print_infinite_recursion_bug();
/*
* Check this lock's dependency list:
if (depth > max_recursion_depth)
max_recursion_depth = depth;
- if (depth >= 20)
+ if (depth >= RECURSION_LIMIT)
return print_infinite_recursion_bug();
debug_atomic_inc(&nr_find_usage_forwards_checks);
if (depth > max_recursion_depth)
max_recursion_depth = depth;
- if (depth >= 20)
+ if (depth >= RECURSION_LIMIT)
return print_infinite_recursion_bug();
debug_atomic_inc(&nr_find_usage_backwards_checks);
printk("\n======================================================\n");
printk( "[ INFO: %s-safe -> %s-unsafe lock order detected ]\n",
irqclass, irqclass);
+ print_kernel_version();
printk( "------------------------------------------------------\n");
printk("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] is trying to acquire:\n",
curr->comm, curr->pid,
printk("\n=============================================\n");
printk( "[ INFO: possible recursive locking detected ]\n");
+ print_kernel_version();
printk( "---------------------------------------------\n");
printk("%s/%d is trying to acquire lock:\n",
curr->comm, curr->pid);
return count + 1;
}
-extern void __error_too_big_MAX_LOCKDEP_SUBCLASSES(void);
-
/*
* Register a lock's class in the hash-table, if the class is not present
* yet. Otherwise we look it up. We cache the result in the lock object
* itself, so actual lookup of the hash should be once per lock object.
*/
static inline struct lock_class *
-register_lock_class(struct lockdep_map *lock, unsigned int subclass)
+look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
{
struct lockdep_subclass_key *key;
struct list_head *hash_head;
* (or spin_lock_init()) call - which acts as the key. For static
* locks we use the lock object itself as the key.
*/
- if (sizeof(struct lock_class_key) > sizeof(struct lock_class))
- __error_too_big_MAX_LOCKDEP_SUBCLASSES();
+ BUILD_BUG_ON(sizeof(struct lock_class_key) > sizeof(struct lock_class));
key = lock->key->subkeys + subclass;
*/
list_for_each_entry(class, hash_head, hash_entry)
if (class->key == key)
- goto out_set;
+ return class;
+
+ return NULL;
+}
+
+/*
+ * Register a lock's class in the hash-table, if the class is not present
+ * yet. Otherwise we look it up. We cache the result in the lock object
+ * itself, so actual lookup of the hash should be once per lock object.
+ */
+static inline struct lock_class *
+register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
+{
+ struct lockdep_subclass_key *key;
+ struct list_head *hash_head;
+ struct lock_class *class;
+
+ class = look_up_lock_class(lock, subclass);
+ if (likely(class))
+ return class;
/*
* Debug-check: all keys must be persistent!
return NULL;
}
+ key = lock->key->subkeys + subclass;
+ hash_head = classhashentry(key);
+
__raw_spin_lock(&hash_lock);
/*
* We have to do the hash-walk again, to avoid races
out_unlock_set:
__raw_spin_unlock(&hash_lock);
-out_set:
- lock->class[subclass] = class;
+ if (!subclass || force)
+ lock->class_cache = class;
DEBUG_LOCKS_WARN_ON(class->subclass != subclass);
printk("\n=========================================================\n");
printk( "[ INFO: possible irq lock inversion dependency detected ]\n");
+ print_kernel_version();
printk( "---------------------------------------------------------\n");
printk("%s/%d just changed the state of lock:\n",
curr->comm, curr->pid);
printk("\n=================================\n");
printk( "[ INFO: inconsistent lock state ]\n");
+ print_kernel_version();
printk( "---------------------------------\n");
printk("inconsistent {%s} -> {%s} usage.\n",
* Initialize a lock instance's lock-class mapping info:
*/
void lockdep_init_map(struct lockdep_map *lock, const char *name,
- struct lock_class_key *key)
+ struct lock_class_key *key, int subclass)
{
if (unlikely(!debug_locks))
return;
}
lock->name = name;
lock->key = key;
- memset(lock->class, 0, sizeof(lock->class[0])*MAX_LOCKDEP_SUBCLASSES);
+ lock->class_cache = NULL;
+ if (subclass)
+ register_lock_class(lock, subclass, 1);
}
EXPORT_SYMBOL_GPL(lockdep_init_map);
unsigned long ip)
{
struct task_struct *curr = current;
+ struct lock_class *class = NULL;
struct held_lock *hlock;
- struct lock_class *class;
unsigned int depth, id;
int chain_head = 0;
u64 chain_key;
return 0;
}
- class = lock->class[subclass];
- /* not cached yet? */
+ if (!subclass)
+ class = lock->class_cache;
+ /*
+ * Not cached yet or subclass?
+ */
if (unlikely(!class)) {
- class = register_lock_class(lock, subclass);
+ class = register_lock_class(lock, subclass, 0);
if (!class)
return 0;
}
void lockdep_reset_lock(struct lockdep_map *lock)
{
- struct lock_class *class, *next, *entry;
+ struct lock_class *class, *next;
struct list_head *head;
unsigned long flags;
int i, j;
raw_local_irq_save(flags);
- __raw_spin_lock(&hash_lock);
/*
- * Remove all classes this lock has:
+ * Remove all classes this lock might have:
+ */
+ for (j = 0; j < MAX_LOCKDEP_SUBCLASSES; j++) {
+ /*
+ * If the class exists we look it up and zap it:
+ */
+ class = look_up_lock_class(lock, j);
+ if (class)
+ zap_class(class);
+ }
+ /*
+ * Debug check: in the end all mapped classes should
+ * be gone.
*/
+ __raw_spin_lock(&hash_lock);
for (i = 0; i < CLASSHASH_SIZE; i++) {
head = classhash_table + i;
if (list_empty(head))
continue;
list_for_each_entry_safe(class, next, head, hash_entry) {
- for (j = 0; j < MAX_LOCKDEP_SUBCLASSES; j++) {
- entry = lock->class[j];
- if (class == entry) {
- zap_class(class);
- lock->class[j] = NULL;
- break;
- }
+ if (unlikely(class == lock->class_cache)) {
+ __raw_spin_unlock(&hash_lock);
+ DEBUG_LOCKS_WARN_ON(1);
+ goto out_restore;
}
}
}
-
- /*
- * Debug check: in the end all mapped classes should
- * be gone.
- */
- for (j = 0; j < MAX_LOCKDEP_SUBCLASSES; j++) {
- entry = lock->class[j];
- if (!entry)
- continue;
- __raw_spin_unlock(&hash_lock);
- DEBUG_LOCKS_WARN_ON(1);
- raw_local_irq_restore(flags);
- return;
- }
-
__raw_spin_unlock(&hash_lock);
+
+out_restore:
raw_local_irq_restore(flags);
}
static void
print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
- const void *mem_to)
+ const void *mem_to, struct held_lock *hlock)
{
if (!debug_locks_off())
return;
printk( "-------------------------\n");
printk("%s/%d is freeing memory %p-%p, with a lock still held there!\n",
curr->comm, curr->pid, mem_from, mem_to-1);
+ print_lock(hlock);
lockdep_print_held_locks(curr);
printk("\nstack backtrace:\n");
!in_range(mem_from, lock_to, mem_to))
continue;
- print_freed_lock_bug(curr, mem_from, mem_to);
+ print_freed_lock_bug(curr, mem_from, mem_to, hlock);
break;
}
local_irq_restore(flags);