1 files changed, 47 insertions, 40 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 1016b75b026a..625985e70e9d 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -59,8 +59,6 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/module.h>
 
-EXPORT_TRACEPOINT_SYMBOL(module_get);
-
 #if 0
 #define DEBUGP printk
 #else
@@ -79,6 +77,10 @@ EXPORT_TRACEPOINT_SYMBOL(module_get);
 DEFINE_MUTEX(module_mutex);
 EXPORT_SYMBOL_GPL(module_mutex);
 static LIST_HEAD(modules);
+#ifdef CONFIG_KGDB_KDB
+struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
+#endif /* CONFIG_KGDB_KDB */
+
 
 /* Block module loading/unloading? */
 int modules_disabled = 0;
@@ -178,8 +180,6 @@ extern const struct kernel_symbol __start___ksymtab_gpl[];
 extern const struct kernel_symbol __stop___ksymtab_gpl[];
 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
-extern const struct kernel_symbol __start___ksymtab_gpl_future[];
-extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
 extern const unsigned long __start___kcrctab[];
 extern const unsigned long __start___kcrctab_gpl[];
 extern const unsigned long __start___kcrctab_gpl_future[];
@@ -515,6 +515,9 @@ MODINFO_ATTR(srcversion);
 static char last_unloaded_module[MODULE_NAME_LEN+1];
 
 #ifdef CONFIG_MODULE_UNLOAD
+
+EXPORT_TRACEPOINT_SYMBOL(module_get);
+
 /* Init the unload section of the module. */
 static void module_unload_init(struct module *mod)
 {
@@ -560,33 +563,26 @@ int use_module(struct module *a, struct module *b)
         struct module_use *use;
         int no_warn, err;
 
-        if (b == NULL || already_uses(a, b)) return 1;
-
-        /* If we're interrupted or time out, we fail. */
-        if (wait_event_interruptible_timeout(
-                    module_wq, (err = strong_try_module_get(b)) != -EBUSY,
-                    30 * HZ) <= 0) {
-                printk("%s: gave up waiting for init of module %s.\n",
-                       a->name, b->name);
+        if (b == NULL || already_uses(a, b))
                 return 0;
-        }
 
-        /* If strong_try_module_get() returned a different error, we fail. */
+        /* If we're interrupted or time out, we fail. */
+        err = strong_try_module_get(b);
         if (err)
-                return 0;
+                return err;
 
         DEBUGP("Allocating new usage for %s.\n", a->name);
         use = kmalloc(sizeof(*use), GFP_ATOMIC);
         if (!use) {
                 printk("%s: out of memory loading\n", a->name);
                 module_put(b);
-                return 0;
+                return -ENOMEM;
         }
 
         use->module_which_uses = a;
         list_add(&use->list, &b->modules_which_use_me);
         no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
-        return 1;
+        return 0;
 }
 EXPORT_SYMBOL_GPL(use_module);
 
@@ -723,16 +719,8 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
                 return -EFAULT;
         name[MODULE_NAME_LEN-1] = '\0';
 
-        /* Create stop_machine threads since free_module relies on
-         * a non-failing stop_machine call. */
-        ret = stop_machine_create();
-        if (ret)
-                return ret;
-
-        if (mutex_lock_interruptible(&module_mutex) != 0) {
-                ret = -EINTR;
-                goto out_stop;
-        }
+        if (mutex_lock_interruptible(&module_mutex) != 0)
+                return -EINTR;
 
         mod = find_module(name);
         if (!mod) {
@@ -792,8 +780,6 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 
  out:
         mutex_unlock(&module_mutex);
-out_stop:
-        stop_machine_destroy();
         return ret;
 }
 
@@ -867,8 +853,7 @@ void module_put(struct module *module)
                 smp_wmb(); /* see comment in module_refcount */
                 __this_cpu_inc(module->refptr->decs);
 
-                trace_module_put(module, _RET_IP_,
-                                 __this_cpu_read(module->refptr->decs));
+                trace_module_put(module, _RET_IP_);
                 /* Maybe they're waiting for us to drop reference? */
                 if (unlikely(!module_is_live(module)))
                         wake_up_process(module->waiter);
@@ -890,7 +875,7 @@ static inline void module_unload_free(struct module *mod)
 
 int use_module(struct module *a, struct module *b)
 {
-        return strong_try_module_get(b) == 0;
+        return strong_try_module_get(b);
 }
 EXPORT_SYMBOL_GPL(use_module);
 
@@ -1061,17 +1046,39 @@ static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
         struct module *owner;
         const struct kernel_symbol *sym;
         const unsigned long *crc;
+        DEFINE_WAIT(wait);
+        int err;
+        long timeleft = 30 * HZ;
 
+again:
         sym = find_symbol(name, &owner, &crc,
                           !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
-        /* use_module can fail due to OOM,
-           or module initialization or unloading */
-        if (sym) {
-                if (!check_version(sechdrs, versindex, name, mod, crc, owner)
-                    || !use_module(mod, owner))
-                        sym = NULL;
+        if (!sym)
+                return NULL;
+
+        if (!check_version(sechdrs, versindex, name, mod, crc, owner))
+                return NULL;
+
+        prepare_to_wait(&module_wq, &wait, TASK_INTERRUPTIBLE);
+        err = use_module(mod, owner);
+        if (likely(!err) || err != -EBUSY || signal_pending(current)) {
+                finish_wait(&module_wq, &wait);
+                return err ? NULL : sym;
         }
-        return sym;
+
+        /* Module is still loading.  Drop lock and wait. */
+        mutex_unlock(&module_mutex);
+        timeleft = schedule_timeout(timeleft);
+        mutex_lock(&module_mutex);
+        finish_wait(&module_wq, &wait);
+
+        /* Module might be gone entirely, or replaced.  Re-lookup. */
+        if (timeleft)
+                goto again;
+
+        printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
+               mod->name, owner->name);
+        return NULL;
 }
 
 /*
@@ -1192,7 +1199,7 @@ struct module_notes_attrs {
         struct bin_attribute attrs[0];
 };
 
-static ssize_t module_notes_read(struct kobject *kobj,
+static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
                                  struct bin_attribute *bin_attr,
                                  char *buf, loff_t pos, size_t count)
 {