4 files changed, 41 insertions, 13 deletions

diff --git a/lib/bug.c b/lib/bug.c
index bfeafd60ee9f..300e41afbf97 100644
--- a/lib/bug.c
+++ b/lib/bug.c
@@ -5,6 +5,8 @@
 
   CONFIG_BUG - emit BUG traps.  Nothing happens without this.
   CONFIG_GENERIC_BUG - enable this code.
+  CONFIG_GENERIC_BUG_RELATIVE_POINTERS - use 32-bit pointers relative to
+        the containing struct bug_entry for bug_addr and file.
   CONFIG_DEBUG_BUGVERBOSE - emit full file+line information for each BUG
 
   CONFIG_BUG and CONFIG_DEBUG_BUGVERBOSE are potentially user-settable
@@ -43,6 +45,15 @@
 
 extern const struct bug_entry __start___bug_table[], __stop___bug_table[];
 
+static inline unsigned long bug_addr(const struct bug_entry *bug)
+{
+#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
+        return bug->bug_addr;
+#else
+        return (unsigned long)bug + bug->bug_addr_disp;
+#endif
+}
+
 #ifdef CONFIG_MODULES
 static LIST_HEAD(module_bug_list);
 
@@ -55,7 +66,7 @@ static const struct bug_entry *module_find_bug(unsigned long bugaddr)
                 unsigned i;
 
                 for (i = 0; i < mod->num_bugs; ++i, ++bug)
-                        if (bugaddr == bug->bug_addr)
+                        if (bugaddr == bug_addr(bug))
                                 return bug;
         }
         return NULL;
@@ -108,7 +119,7 @@ const struct bug_entry *find_bug(unsigned long bugaddr)
         const struct bug_entry *bug;
 
         for (bug = __start___bug_table; bug < __stop___bug_table; ++bug)
-                if (bugaddr == bug->bug_addr)
+                if (bugaddr == bug_addr(bug))
                         return bug;
 
         return module_find_bug(bugaddr);
@@ -133,7 +144,11 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
 
         if (bug) {
 #ifdef CONFIG_DEBUG_BUGVERBOSE
+#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
                 file = bug->file;
+#else
+                file = (const char *)bug + bug->file_disp;
+#endif
                 line = bug->line;
 #endif
                 warning = (bug->flags & BUGFLAG_WARNING) != 0;
diff --git a/lib/dynamic_printk.c b/lib/dynamic_printk.c
index d83660fd6fdd..8e30295e8566 100644
--- a/lib/dynamic_printk.c
+++ b/lib/dynamic_printk.c
@@ -135,7 +135,7 @@ int unregister_dynamic_debug_module(char *mod_name)
         nr_entries--;
 out:
         up(&debug_list_mutex);
-        return 0;
+        return ret;
 }
 EXPORT_SYMBOL_GPL(unregister_dynamic_debug_module);
 
@@ -289,7 +289,7 @@ static ssize_t pr_debug_write(struct file *file, const char __user *buf,
                                         dynamic_enabled = DYNAMIC_ENABLED_SOME;
                                         err = 0;
                                         printk(KERN_DEBUG
-                                               "debugging enabled for module %s",
+                                               "debugging enabled for module %s\n",
                                                elem->name);
                                 } else if (!value && (elem->enable == 1)) {
                                         elem->enable = 0;
@@ -309,7 +309,7 @@ static ssize_t pr_debug_write(struct file *file, const char __user *buf,
                                         err = 0;
                                         printk(KERN_DEBUG
                                                "debugging disabled for module "
-                                               "%s", elem->name);
+                                               "%s\n", elem->name);
                                 }
                         }
                 }
diff --git a/lib/idr.c b/lib/idr.c
index e728c7fccc4d..1c4f9281f412 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -185,6 +185,7 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa)
                         new = get_from_free_list(idp);
                         if (!new)
                                 return -1;
+                        new->layer = l-1;
                         rcu_assign_pointer(p->ary[m], new);
                         p->count++;
                 }
@@ -210,6 +211,7 @@ build_up:
         if (unlikely(!p)) {
                 if (!(p = get_from_free_list(idp)))
                         return -1;
+                p->layer = 0;
                 layers = 1;
         }
         /*
@@ -218,8 +220,14 @@ build_up:
          */
         while ((layers < (MAX_LEVEL - 1)) && (id >= (1 << (layers*IDR_BITS)))) {
                 layers++;
-                if (!p->count)
+                if (!p->count) {
+                        /* special case: if the tree is currently empty,
+                         * then we grow the tree by moving the top node
+                         * upwards.
+                         */
+                        p->layer++;
                         continue;
+                }
                 if (!(new = get_from_free_list(idp))) {
                         /*
                          * The allocation failed.  If we built part of
@@ -237,6 +245,7 @@ build_up:
                 }
                 new->ary[0] = p;
                 new->count = 1;
+                new->layer = layers-1;
                 if (p->bitmap == IDR_FULL)
                         __set_bit(0, &new->bitmap);
                 p = new;
@@ -493,17 +502,21 @@ void *idr_find(struct idr *idp, int id)
         int n;
         struct idr_layer *p;
 
-        n = idp->layers * IDR_BITS;
         p = rcu_dereference(idp->top);
+        if (!p)
+                return NULL;
+        n = (p->layer+1) * IDR_BITS;
 
         /* Mask off upper bits we don't use for the search. */
         id &= MAX_ID_MASK;
 
         if (id >= (1 << n))
                 return NULL;
+        BUG_ON(n == 0);
 
         while (n > 0 && p) {
                 n -= IDR_BITS;
+                BUG_ON(n != p->layer*IDR_BITS);
                 p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]);
         }
         return((void *)p);
@@ -582,8 +595,11 @@ void *idr_replace(struct idr *idp, void *ptr, int id)
         int n;
         struct idr_layer *p, *old_p;
 
-        n = idp->layers * IDR_BITS;
         p = idp->top;
+        if (!p)
+                return ERR_PTR(-EINVAL);
+
+        n = (p->layer+1) * IDR_BITS;
 
         id &= MAX_ID_MASK;
 
diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
index a8663890a88c..b255b939bc1b 100644
--- a/lib/percpu_counter.c
+++ b/lib/percpu_counter.c
@@ -62,10 +62,7 @@ s64 __percpu_counter_sum(struct percpu_counter *fbc)
         for_each_online_cpu(cpu) {
                 s32 *pcount = per_cpu_ptr(fbc->counters, cpu);
                 ret += *pcount;
-                *pcount = 0;
         }
-        fbc->count = ret;
-
         spin_unlock(&fbc->lock);
         return ret;
 }
@@ -104,13 +101,13 @@ void percpu_counter_destroy(struct percpu_counter *fbc)
         if (!fbc->counters)
                 return;
 
-        free_percpu(fbc->counters);
-        fbc->counters = NULL;
 #ifdef CONFIG_HOTPLUG_CPU
         mutex_lock(&percpu_counters_lock);
         list_del(&fbc->list);
         mutex_unlock(&percpu_counters_lock);
 #endif
+        free_percpu(fbc->counters);
+        fbc->counters = NULL;
 }
 EXPORT_SYMBOL(percpu_counter_destroy);