1 files changed, 26 insertions, 16 deletions

diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index ed38bbfc48a3..723bd9f92556 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -2654,10 +2654,15 @@ static void check_flags(unsigned long flags)
         if (!debug_locks)
                 return;
 
-        if (irqs_disabled_flags(flags))
-                DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled);
-        else
-                DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled);
+        if (irqs_disabled_flags(flags)) {
+                if (DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)) {
+                        printk("possible reason: unannotated irqs-off.\n");
+                }
+        } else {
+                if (DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled)) {
+                        printk("possible reason: unannotated irqs-on.\n");
+                }
+        }
 
         /*
          * We dont accurately track softirq state in e.g.
@@ -3054,11 +3059,6 @@ void __init lockdep_info(void)
 #endif
 }
 
-static inline int in_range(const void *start, const void *addr, const void *end)
-{
-        return addr >= start && addr <= end;
-}
-
 static void
 print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
                      const void *mem_to, struct held_lock *hlock)
@@ -3080,6 +3080,13 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
         dump_stack();
 }
 
+static inline int not_in_range(const void* mem_from, unsigned long mem_len,
+                                const void* lock_from, unsigned long lock_len)
+{
+        return lock_from + lock_len <= mem_from ||
+                mem_from + mem_len <= lock_from;
+}
+
 /*
  * Called when kernel memory is freed (or unmapped), or if a lock
  * is destroyed or reinitialized - this code checks whether there is
@@ -3087,7 +3094,6 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
  */
 void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len)
 {
-        const void *mem_to = mem_from + mem_len, *lock_from, *lock_to;
         struct task_struct *curr = current;
         struct held_lock *hlock;
         unsigned long flags;
@@ -3100,14 +3106,11 @@ void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len)
         for (i = 0; i < curr->lockdep_depth; i++) {
                 hlock = curr->held_locks + i;
 
-                lock_from = (void *)hlock->instance;
-                lock_to = (void *)(hlock->instance + 1);
-
-                if (!in_range(mem_from, lock_from, mem_to) &&
-                                        !in_range(mem_from, lock_to, mem_to))
+                if (not_in_range(mem_from, mem_len, hlock->instance,
+                                        sizeof(*hlock->instance)))
                         continue;
 
-                print_freed_lock_bug(curr, mem_from, mem_to, hlock);
+                print_freed_lock_bug(curr, mem_from, mem_from + mem_len, hlock);
                 break;
         }
         local_irq_restore(flags);
@@ -3173,6 +3176,13 @@ retry:
                 printk(" locked it.\n");
 
         do_each_thread(g, p) {
+                /*
+                 * It's not reliable to print a task's held locks
+                 * if it's not sleeping (or if it's not the current
+                 * task):
+                 */
+                if (p->state == TASK_RUNNING && p != current)
+                        continue;
                 if (p->lockdep_depth)
                         lockdep_print_held_locks(p);
                 if (!unlock)