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-rw-r--r--kernel/module.c28
1 files changed, 23 insertions, 5 deletions
diff --git a/kernel/module.c b/kernel/module.c
index 1bb4c5e0d56e..17314691d3cc 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -65,6 +65,9 @@
static DEFINE_MUTEX(module_mutex);
static LIST_HEAD(modules);
+/* Waiting for a module to finish initializing? */
+static DECLARE_WAIT_QUEUE_HEAD(module_wq);
+
static BLOCKING_NOTIFIER_HEAD(module_notify_list);
int register_module_notifier(struct notifier_block * nb)
@@ -84,8 +87,11 @@ EXPORT_SYMBOL(unregister_module_notifier);
static inline int strong_try_module_get(struct module *mod)
{
if (mod && mod->state == MODULE_STATE_COMING)
+ return -EBUSY;
+ if (try_module_get(mod))
return 0;
- return try_module_get(mod);
+ else
+ return -ENOENT;
}
static inline void add_taint_module(struct module *mod, unsigned flag)
@@ -539,11 +545,21 @@ static int already_uses(struct module *a, struct module *b)
static int use_module(struct module *a, struct module *b)
{
struct module_use *use;
- int no_warn;
+ int no_warn, err;
if (b == NULL || already_uses(a, b)) return 1;
- if (!strong_try_module_get(b))
+ /* 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);
+ return 0;
+ }
+
+ /* If strong_try_module_get() returned a different error, we fail. */
+ if (err)
return 0;
DEBUGP("Allocating new usage for %s.\n", a->name);
@@ -816,7 +832,7 @@ static inline void module_unload_free(struct module *mod)
static inline int use_module(struct module *a, struct module *b)
{
- return strong_try_module_get(b);
+ return strong_try_module_get(b) == 0;
}
static inline void module_unload_init(struct module *mod)
@@ -1326,7 +1342,7 @@ void *__symbol_get(const char *symbol)
preempt_disable();
value = __find_symbol(symbol, &owner, &crc, 1);
- if (value && !strong_try_module_get(owner))
+ if (value && strong_try_module_get(owner) != 0)
value = 0;
preempt_enable();
@@ -2132,6 +2148,7 @@ sys_init_module(void __user *umod,
mutex_lock(&module_mutex);
free_module(mod);
mutex_unlock(&module_mutex);
+ wake_up(&module_wq);
return ret;
}
@@ -2146,6 +2163,7 @@ sys_init_module(void __user *umod,
mod->init_size = 0;
mod->init_text_size = 0;
mutex_unlock(&module_mutex);
+ wake_up(&module_wq);
return 0;
}
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