lockdep/waitqueues: Add better annotation

[cascardo/linux.git] / kernel / lockdep.c

diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index e69434b..e69d633 100644 (file)
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -44,6 +44,7 @@
 #include <linux/stringify.h>
 #include <linux/bitops.h>
 #include <linux/gfp.h>
+#include <linux/kmemcheck.h>
 
 #include <asm/sections.h>
 
@@ -430,6 +431,7 @@ unsigned int max_lockdep_depth;
  * about it later on, in lockdep_info().
  */
 static int lockdep_init_error;
+static const char *lock_init_error;
 static unsigned long lockdep_init_trace_data[20];
 static struct stack_trace lockdep_init_trace = {
        .max_entries = ARRAY_SIZE(lockdep_init_trace_data),
@@ -567,11 +569,12 @@ static void lockdep_print_held_locks(struct task_struct *curr)
        }
 }
 
-static void print_kernel_version(void)
+static void print_kernel_ident(void)
 {
-       printk("%s %.*s\n", init_utsname()->release,
+       printk("%s %.*s %s\n", init_utsname()->release,
                (int)strcspn(init_utsname()->version, " "),
-               init_utsname()->version);
+               init_utsname()->version,
+               print_tainted());
 }
 
 static int very_verbose(struct lock_class *class)
@@ -655,6 +658,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
        if (unlikely(!lockdep_initialized)) {
                lockdep_init();
                lockdep_init_error = 1;
+               lock_init_error = lock->name;
                save_stack_trace(&lockdep_init_trace);
        }
 #endif
@@ -722,7 +726,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
 
        class = look_up_lock_class(lock, subclass);
        if (likely(class))
-               return class;
+               goto out_set_class_cache;
 
        /*
         * Debug-check: all keys must be persistent!
@@ -807,6 +811,7 @@ out_unlock_set:
        graph_unlock();
        raw_local_irq_restore(flags);
 
+out_set_class_cache:
        if (!subclass || force)
                lock->class_cache[0] = class;
        else if (subclass < NR_LOCKDEP_CACHING_CLASSES)
@@ -1148,7 +1153,7 @@ print_circular_bug_header(struct lock_list *entry, unsigned int depth,
        printk("\n");
        printk("======================================================\n");
        printk("[ INFO: possible circular locking dependency detected ]\n");
-       print_kernel_version();
+       print_kernel_ident();
        printk("-------------------------------------------------------\n");
        printk("%s/%d is trying to acquire lock:\n",
                curr->comm, task_pid_nr(curr));
@@ -1487,7 +1492,7 @@ print_bad_irq_dependency(struct task_struct *curr,
        printk("======================================================\n");
        printk("[ INFO: %s-safe -> %s-unsafe lock order detected ]\n",
                irqclass, irqclass);
-       print_kernel_version();
+       print_kernel_ident();
        printk("------------------------------------------------------\n");
        printk("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] is trying to acquire:\n",
                curr->comm, task_pid_nr(curr),
@@ -1716,7 +1721,7 @@ print_deadlock_bug(struct task_struct *curr, struct held_lock *prev,
        printk("\n");
        printk("=============================================\n");
        printk("[ INFO: possible recursive locking detected ]\n");
-       print_kernel_version();
+       print_kernel_ident();
        printk("---------------------------------------------\n");
        printk("%s/%d is trying to acquire lock:\n",
                curr->comm, task_pid_nr(curr));
@@ -2223,7 +2228,7 @@ print_usage_bug(struct task_struct *curr, struct held_lock *this,
        printk("\n");
        printk("=================================\n");
        printk("[ INFO: inconsistent lock state ]\n");
-       print_kernel_version();
+       print_kernel_ident();
        printk("---------------------------------\n");
 
        printk("inconsistent {%s} -> {%s} usage.\n",
@@ -2288,7 +2293,7 @@ print_irq_inversion_bug(struct task_struct *curr,
        printk("\n");
        printk("=========================================================\n");
        printk("[ INFO: possible irq lock inversion dependency detected ]\n");
-       print_kernel_version();
+       print_kernel_ident();
        printk("---------------------------------------------------------\n");
        printk("%s/%d just changed the state of lock:\n",
                curr->comm, task_pid_nr(curr));
@@ -2948,7 +2953,12 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
 void lockdep_init_map(struct lockdep_map *lock, const char *name,
                      struct lock_class_key *key, int subclass)
 {
-       memset(lock, 0, sizeof(*lock));
+       int i;
+
+       kmemcheck_mark_initialized(lock, sizeof(*lock));
+
+       for (i = 0; i < NR_LOCKDEP_CACHING_CLASSES; i++)
+               lock->class_cache[i] = NULL;
 
 #ifdef CONFIG_LOCK_STAT
        lock->cpu = raw_smp_processor_id();
@@ -3169,6 +3179,7 @@ print_unlock_inbalance_bug(struct task_struct *curr, struct lockdep_map *lock,
        printk("\n");
        printk("=====================================\n");
        printk("[ BUG: bad unlock balance detected! ]\n");
+       print_kernel_ident();
        printk("-------------------------------------\n");
        printk("%s/%d is trying to release lock (",
                curr->comm, task_pid_nr(curr));
@@ -3613,6 +3624,7 @@ print_lock_contention_bug(struct task_struct *curr, struct lockdep_map *lock,
        printk("\n");
        printk("=================================\n");
        printk("[ BUG: bad contention detected! ]\n");
+       print_kernel_ident();
        printk("---------------------------------\n");
        printk("%s/%d is trying to contend lock (",
                curr->comm, task_pid_nr(curr));
@@ -3968,7 +3980,8 @@ void __init lockdep_info(void)
 
 #ifdef CONFIG_DEBUG_LOCKDEP
        if (lockdep_init_error) {
-               printk("WARNING: lockdep init error! Arch code didn't call lockdep_init() early enough?\n");
+               printk("WARNING: lockdep init error! lock-%s was acquired"
+                       "before lockdep_init\n", lock_init_error);
                printk("Call stack leading to lockdep invocation was:\n");
                print_stack_trace(&lockdep_init_trace, 0);
        }
@@ -3987,6 +4000,7 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
        printk("\n");
        printk("=========================\n");
        printk("[ BUG: held lock freed! ]\n");
+       print_kernel_ident();
        printk("-------------------------\n");
        printk("%s/%d is freeing memory %p-%p, with a lock still held there!\n",
                curr->comm, task_pid_nr(curr), mem_from, mem_to-1);
@@ -4044,6 +4058,7 @@ static void print_held_locks_bug(struct task_struct *curr)
        printk("\n");
        printk("=====================================\n");
        printk("[ BUG: lock held at task exit time! ]\n");
+       print_kernel_ident();
        printk("-------------------------------------\n");
        printk("%s/%d is exiting with locks still held!\n",
                curr->comm, task_pid_nr(curr));
@@ -4141,6 +4156,7 @@ void lockdep_sys_exit(void)
                printk("\n");
                printk("================================================\n");
                printk("[ BUG: lock held when returning to user space! ]\n");
+               print_kernel_ident();
                printk("------------------------------------------------\n");
                printk("%s/%d is leaving the kernel with locks still held!\n",
                                curr->comm, curr->pid);
@@ -4160,6 +4176,7 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s)
        printk("\n");
        printk("===============================\n");
        printk("[ INFO: suspicious RCU usage. ]\n");
+       print_kernel_ident();
        printk("-------------------------------\n");
        printk("%s:%d %s!\n", file, line, s);
        printk("\nother info that might help us debug this:\n\n");