diff options
| -rw-r--r-- | kernel/module.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/kernel/module.c b/kernel/module.c index 63cf6e7..74bc195 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2845,6 +2845,20 @@ static int post_relocation(struct module *mod, const struct load_info *info) return module_finalize(info->hdr, info->sechdrs, mod); } +/* Is this module of this name done loading? No locks held. */ +static bool finished_loading(const char *name) +{ + struct module *mod; + bool ret; + + mutex_lock(&module_mutex); + mod = find_module(name); + ret = !mod || mod->state != MODULE_STATE_COMING; + mutex_unlock(&module_mutex); + + return ret; +} + /* Allocate and load the module: note that size of section 0 is always zero, and we rely on this for optional sections. */ static struct module *load_module(void __user *umod, @@ -2852,7 +2866,7 @@ static struct module *load_module(void __user *umod, const char __user *uargs) { struct load_info info = { NULL, }; - struct module *mod; + struct module *mod, *old; long err; pr_debug("load_module: umod=%p, len=%lu, uargs=%p\n", @@ -2918,8 +2932,18 @@ static struct module *load_module(void __user *umod, * function to insert in a way safe to concurrent readers. * The mutex protects against concurrent writers. */ +again: mutex_lock(&module_mutex); - if (find_module(mod->name)) { + if ((old = find_module(mod->name)) != NULL) { + if (old->state == MODULE_STATE_COMING) { + /* Wait in case it fails to load. */ + mutex_unlock(&module_mutex); + err = wait_event_interruptible(module_wq, + finished_loading(mod->name)); + if (err) + goto free_arch_cleanup; + goto again; + } err = -EEXIST; goto unlock; } |
