1 files changed, 134 insertions, 160 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 3202c9950073..bd60278ee703 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -47,8 +47,6 @@
 #include <asm/cacheflush.h>
 #include <linux/license.h>
 
-extern int module_sysfs_initialized;
-
 #if 0
 #define DEBUGP printk
 #else
@@ -67,6 +65,9 @@ extern int module_sysfs_initialized;
 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)
@@ -81,12 +82,16 @@ int unregister_module_notifier(struct notifier_block * nb)
 }
 EXPORT_SYMBOL(unregister_module_notifier);
 
-/* We require a truly strong try_module_get() */
+/* We require a truly strong try_module_get(): 0 means failure due to
+   ongoing or failed initialization etc. */
 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)
@@ -425,6 +430,14 @@ static unsigned int find_pcpusec(Elf_Ehdr *hdr,
         return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
 }
 
+static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
+{
+        int cpu;
+
+        for_each_possible_cpu(cpu)
+                memcpy(pcpudest + per_cpu_offset(cpu), from, size);
+}
+
 static int percpu_modinit(void)
 {
         pcpu_num_used = 2;
@@ -497,6 +510,8 @@ static struct module_attribute modinfo_##field = {                    \
 MODINFO_ATTR(version);
 MODINFO_ATTR(srcversion);
 
+static char last_unloaded_module[MODULE_NAME_LEN+1];
+
 #ifdef CONFIG_MODULE_UNLOAD
 /* Init the unload section of the module. */
 static void module_unload_init(struct module *mod)
@@ -538,11 +553,21 @@ 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);
@@ -720,6 +745,8 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
                 mod->exit();
                 mutex_lock(&module_mutex);
         }
+        /* Store the name of the last unloaded module for diagnostic purposes */
+        strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
         free_module(mod);
 
  out:
@@ -813,7 +840,7 @@ 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)
@@ -952,7 +979,8 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
         ret = __find_symbol(name, &owner, &crc,
                         !(mod->taints & TAINT_PROPRIETARY_MODULE));
         if (ret) {
-                /* use_module can fail due to OOM, or module unloading */
+                /* use_module can fail due to OOM,
+                   or module initialization or unloading */
                 if (!check_version(sechdrs, versindex, name, mod, crc) ||
                     !use_module(mod, owner))
                         ret = 0;
@@ -1120,7 +1148,7 @@ static void add_notes_attrs(struct module *mod, unsigned int nsect,
                 ++loaded;
         }
 
-        notes_attrs->dir = kobject_add_dir(&mod->mkobj.kobj, "notes");
+        notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
         if (!notes_attrs->dir)
                 goto out;
 
@@ -1210,6 +1238,7 @@ void module_remove_modinfo_attrs(struct module *mod)
 int mod_sysfs_init(struct module *mod)
 {
         int err;
+        struct kobject *kobj;
 
         if (!module_sysfs_initialized) {
                 printk(KERN_ERR "%s: module sysfs not initialized\n",
@@ -1217,15 +1246,25 @@ int mod_sysfs_init(struct module *mod)
                 err = -EINVAL;
                 goto out;
         }
-        memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
-        err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name);
-        if (err)
+
+        kobj = kset_find_obj(module_kset, mod->name);
+        if (kobj) {
+                printk(KERN_ERR "%s: module is already loaded\n", mod->name);
+                kobject_put(kobj);
+                err = -EINVAL;
                 goto out;
-        kobj_set_kset_s(&mod->mkobj, module_subsys);
+        }
+
         mod->mkobj.mod = mod;
 
-        kobject_init(&mod->mkobj.kobj);
+        memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
+        mod->mkobj.kobj.kset = module_kset;
+        err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
+                                   "%s", mod->name);
+        if (err)
+                kobject_put(&mod->mkobj.kobj);
 
+        /* delay uevent until full sysfs population */
 out:
         return err;
 }
@@ -1236,12 +1275,7 @@ int mod_sysfs_setup(struct module *mod,
 {
         int err;
 
-        /* delay uevent until full sysfs population */
-        err = kobject_add(&mod->mkobj.kobj);
-        if (err)
-                goto out;
-
-        mod->holders_dir = kobject_add_dir(&mod->mkobj.kobj, "holders");
+        mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
         if (!mod->holders_dir) {
                 err = -ENOMEM;
                 goto out_unreg;
@@ -1261,11 +1295,9 @@ int mod_sysfs_setup(struct module *mod,
 out_unreg_param:
         module_param_sysfs_remove(mod);
 out_unreg_holders:
-        kobject_unregister(mod->holders_dir);
+        kobject_put(mod->holders_dir);
 out_unreg:
-        kobject_del(&mod->mkobj.kobj);
         kobject_put(&mod->mkobj.kobj);
-out:
         return err;
 }
 #endif
@@ -1274,9 +1306,20 @@ static void mod_kobject_remove(struct module *mod)
 {
         module_remove_modinfo_attrs(mod);
         module_param_sysfs_remove(mod);
-        kobject_unregister(mod->mkobj.drivers_dir);
-        kobject_unregister(mod->holders_dir);
-        kobject_unregister(&mod->mkobj.kobj);
+        kobject_put(mod->mkobj.drivers_dir);
+        kobject_put(mod->holders_dir);
+        kobject_put(&mod->mkobj.kobj);
+}
+
+/*
+ * link the module with the whole machine is stopped with interrupts off
+ * - this defends against kallsyms not taking locks
+ */
+static int __link_module(void *_mod)
+{
+        struct module *mod = _mod;
+        list_add(&mod->list, &modules);
+        return 0;
 }
 
 /*
@@ -1328,7 +1371,7 @@ 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();
 
@@ -1369,7 +1412,7 @@ dup:
         return ret;
 }
 
-/* Change all symbols so that sh_value encodes the pointer directly. */
+/* Change all symbols so that st_value encodes the pointer directly. */
 static int simplify_symbols(Elf_Shdr *sechdrs,
                             unsigned int symindex,
                             const char *strtab,
@@ -1882,16 +1925,16 @@ static struct module *load_module(void __user *umod,
         /* Now we've moved module, initialize linked lists, etc. */
         module_unload_init(mod);
 
-        /* Initialize kobject, so we can reference it. */
+        /* add kobject, so we can reference it. */
         err = mod_sysfs_init(mod);
         if (err)
-                goto cleanup;
+                goto free_unload;
 
         /* Set up license info based on the info section */
         set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
 
         if (strcmp(mod->name, "ndiswrapper") == 0)
-                add_taint(TAINT_PROPRIETARY_MODULE);
+                add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
         if (strcmp(mod->name, "driverloader") == 0)
                 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
 
@@ -2021,6 +2064,11 @@ static struct module *load_module(void __user *umod,
                 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
                        mod->name);
 
+        /* Now sew it into the lists so we can get lockdep and oops
+         * info during argument parsing.  Noone should access us, since
+         * strong_try_module_get() will fail. */
+        stop_machine_run(__link_module, mod, NR_CPUS);
+
         /* Size of section 0 is 0, so this works well if no params */
         err = parse_args(mod->name, mod->args,
                          (struct kernel_param *)
@@ -2029,7 +2077,7 @@ static struct module *load_module(void __user *umod,
                          / sizeof(struct kernel_param),
                          NULL);
         if (err < 0)
-                goto arch_cleanup;
+                goto unlink;
 
         err = mod_sysfs_setup(mod,
                               (struct kernel_param *)
@@ -2037,7 +2085,7 @@ static struct module *load_module(void __user *umod,
                               sechdrs[setupindex].sh_size
                               / sizeof(struct kernel_param));
         if (err < 0)
-                goto arch_cleanup;
+                goto unlink;
         add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
         add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
 
@@ -2052,9 +2100,13 @@ static struct module *load_module(void __user *umod,
         /* Done! */
         return mod;
 
- arch_cleanup:
+ unlink:
+        stop_machine_run(__unlink_module, mod, NR_CPUS);
         module_arch_cleanup(mod);
  cleanup:
+        kobject_del(&mod->mkobj.kobj);
+        kobject_put(&mod->mkobj.kobj);
+ free_unload:
         module_unload_free(mod);
         module_free(mod, mod->module_init);
  free_core:
@@ -2074,17 +2126,6 @@ static struct module *load_module(void __user *umod,
         goto free_hdr;
 }
 
-/*
- * link the module with the whole machine is stopped with interrupts off
- * - this defends against kallsyms not taking locks
- */
-static int __link_module(void *_mod)
-{
-        struct module *mod = _mod;
-        list_add(&mod->list, &modules);
-        return 0;
-}
-
 /* This is where the real work happens */
 asmlinkage long
 sys_init_module(void __user *umod,
@@ -2109,10 +2150,6 @@ sys_init_module(void __user *umod,
                 return PTR_ERR(mod);
         }
 
-        /* Now sew it into the lists.  They won't access us, since
-           strong_try_module_get() will fail. */
-        stop_machine_run(__link_module, mod, NR_CPUS);
-
         /* Drop lock so they can recurse */
         mutex_unlock(&module_mutex);
 
@@ -2131,6 +2168,7 @@ sys_init_module(void __user *umod,
                 mutex_lock(&module_mutex);
                 free_module(mod);
                 mutex_unlock(&module_mutex);
+                wake_up(&module_wq);
                 return ret;
         }
 
@@ -2145,6 +2183,7 @@ 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;
 }
@@ -2209,32 +2248,41 @@ static const char *get_ksymbol(struct module *mod,
         return mod->strtab + mod->symtab[best].st_name;
 }
 
-/* For kallsyms to ask for address resolution.  NULL means not found.
-   We don't lock, as this is used for oops resolution and races are a
-   lesser concern. */
-const char *module_address_lookup(unsigned long addr,
-                                  unsigned long *size,
-                                  unsigned long *offset,
-                                  char **modname)
+/* For kallsyms to ask for address resolution.  NULL means not found.  Careful
+ * not to lock to avoid deadlock on oopses, simply disable preemption. */
+char *module_address_lookup(unsigned long addr,
+                            unsigned long *size,
+                            unsigned long *offset,
+                            char **modname,
+                            char *namebuf)
 {
         struct module *mod;
+        const char *ret = NULL;
 
+        preempt_disable();
         list_for_each_entry(mod, &modules, list) {
                 if (within(addr, mod->module_init, mod->init_size)
                     || within(addr, mod->module_core, mod->core_size)) {
                         if (modname)
                                 *modname = mod->name;
-                        return get_ksymbol(mod, addr, size, offset);
+                        ret = get_ksymbol(mod, addr, size, offset);
+                        break;
                 }
         }
-        return NULL;
+        /* Make a copy in here where it's safe */
+        if (ret) {
+                strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
+                ret = namebuf;
+        }
+        preempt_enable();
+        return (char *)ret;
 }
 
 int lookup_module_symbol_name(unsigned long addr, char *symname)
 {
         struct module *mod;
 
-        mutex_lock(&module_mutex);
+        preempt_disable();
         list_for_each_entry(mod, &modules, list) {
                 if (within(addr, mod->module_init, mod->init_size) ||
                     within(addr, mod->module_core, mod->core_size)) {
@@ -2244,12 +2292,12 @@ int lookup_module_symbol_name(unsigned long addr, char *symname)
                         if (!sym)
                                 goto out;
                         strlcpy(symname, sym, KSYM_NAME_LEN);
-                        mutex_unlock(&module_mutex);
+                        preempt_enable();
                         return 0;
                 }
         }
 out:
-        mutex_unlock(&module_mutex);
+        preempt_enable();
         return -ERANGE;
 }
 
@@ -2258,7 +2306,7 @@ int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
 {
         struct module *mod;
 
-        mutex_lock(&module_mutex);
+        preempt_disable();
         list_for_each_entry(mod, &modules, list) {
                 if (within(addr, mod->module_init, mod->init_size) ||
                     within(addr, mod->module_core, mod->core_size)) {
@@ -2271,12 +2319,12 @@ int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
                                 strlcpy(modname, mod->name, MODULE_NAME_LEN);
                         if (name)
                                 strlcpy(name, sym, KSYM_NAME_LEN);
-                        mutex_unlock(&module_mutex);
+                        preempt_enable();
                         return 0;
                 }
         }
 out:
-        mutex_unlock(&module_mutex);
+        preempt_enable();
         return -ERANGE;
 }
 
@@ -2285,7 +2333,7 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
 {
         struct module *mod;
 
-        mutex_lock(&module_mutex);
+        preempt_disable();
         list_for_each_entry(mod, &modules, list) {
                 if (symnum < mod->num_symtab) {
                         *value = mod->symtab[symnum].st_value;
@@ -2294,12 +2342,12 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
                                 KSYM_NAME_LEN);
                         strlcpy(module_name, mod->name, MODULE_NAME_LEN);
                         *exported = is_exported(name, mod);
-                        mutex_unlock(&module_mutex);
+                        preempt_enable();
                         return 0;
                 }
                 symnum -= mod->num_symtab;
         }
-        mutex_unlock(&module_mutex);
+        preempt_enable();
         return -ERANGE;
 }
 
@@ -2322,6 +2370,7 @@ unsigned long module_kallsyms_lookup_name(const char *name)
         unsigned long ret = 0;
 
         /* Don't lock: we're in enough trouble already. */
+        preempt_disable();
         if ((colon = strchr(name, ':')) != NULL) {
                 *colon = '\0';
                 if ((mod = find_module(name)) != NULL)
@@ -2332,6 +2381,7 @@ unsigned long module_kallsyms_lookup_name(const char *name)
                         if ((ret = mod_find_symname(mod, name)) != 0)
                                 break;
         }
+        preempt_enable();
         return ret;
 }
 #endif /* CONFIG_KALLSYMS */
@@ -2353,21 +2403,30 @@ static void m_stop(struct seq_file *m, void *p)
         mutex_unlock(&module_mutex);
 }
 
-static char *taint_flags(unsigned int taints, char *buf)
+static char *module_flags(struct module *mod, char *buf)
 {
         int bx = 0;
 
-        if (taints) {
+        if (mod->taints ||
+            mod->state == MODULE_STATE_GOING ||
+            mod->state == MODULE_STATE_COMING) {
                 buf[bx++] = '(';
-                if (taints & TAINT_PROPRIETARY_MODULE)
+                if (mod->taints & TAINT_PROPRIETARY_MODULE)
                         buf[bx++] = 'P';
-                if (taints & TAINT_FORCED_MODULE)
+                if (mod->taints & TAINT_FORCED_MODULE)
                         buf[bx++] = 'F';
                 /*
                  * TAINT_FORCED_RMMOD: could be added.
                  * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
                  * apply to modules.
                  */
+
+                /* Show a - for module-is-being-unloaded */
+                if (mod->state == MODULE_STATE_GOING)
+                        buf[bx++] = '-';
+                /* Show a + for module-is-being-loaded */
+                if (mod->state == MODULE_STATE_COMING)
+                        buf[bx++] = '+';
                 buf[bx++] = ')';
         }
         buf[bx] = '\0';
@@ -2394,7 +2453,7 @@ static int m_show(struct seq_file *m, void *p)
 
         /* Taints info */
         if (mod->taints)
-                seq_printf(m, " %s", taint_flags(mod->taints, buf));
+                seq_printf(m, " %s", module_flags(mod, buf));
 
         seq_printf(m, "\n");
         return 0;
@@ -2489,97 +2548,12 @@ void print_modules(void)
 
         printk("Modules linked in:");
         list_for_each_entry(mod, &modules, list)
-                printk(" %s%s", mod->name, taint_flags(mod->taints, buf));
+                printk(" %s%s", mod->name, module_flags(mod, buf));
+        if (last_unloaded_module[0])
+                printk(" [last unloaded: %s]", last_unloaded_module);
         printk("\n");
 }
 
-#ifdef CONFIG_SYSFS
-static char *make_driver_name(struct device_driver *drv)
-{
-        char *driver_name;
-
-        driver_name = kmalloc(strlen(drv->name) + strlen(drv->bus->name) + 2,
-                              GFP_KERNEL);
-        if (!driver_name)
-                return NULL;
-
-        sprintf(driver_name, "%s:%s", drv->bus->name, drv->name);
-        return driver_name;
-}
-
-static void module_create_drivers_dir(struct module_kobject *mk)
-{
-        if (!mk || mk->drivers_dir)
-                return;
-
-        mk->drivers_dir = kobject_add_dir(&mk->kobj, "drivers");
-}
-
-void module_add_driver(struct module *mod, struct device_driver *drv)
-{
-        char *driver_name;
-        int no_warn;
-        struct module_kobject *mk = NULL;
-
-        if (!drv)
-                return;
-
-        if (mod)
-                mk = &mod->mkobj;
-        else if (drv->mod_name) {
-                struct kobject *mkobj;
-
-                /* Lookup built-in module entry in /sys/modules */
-                mkobj = kset_find_obj(&module_subsys, drv->mod_name);
-                if (mkobj) {
-                        mk = container_of(mkobj, struct module_kobject, kobj);
-                        /* remember our module structure */
-                        drv->mkobj = mk;
-                        /* kset_find_obj took a reference */
-                        kobject_put(mkobj);
-                }
-        }
-
-        if (!mk)
-                return;
-
-        /* Don't check return codes; these calls are idempotent */
-        no_warn = sysfs_create_link(&drv->kobj, &mk->kobj, "module");
-        driver_name = make_driver_name(drv);
-        if (driver_name) {
-                module_create_drivers_dir(mk);
-                no_warn = sysfs_create_link(mk->drivers_dir, &drv->kobj,
-                                            driver_name);
-                kfree(driver_name);
-        }
-}
-EXPORT_SYMBOL(module_add_driver);
-
-void module_remove_driver(struct device_driver *drv)
-{
-        struct module_kobject *mk = NULL;
-        char *driver_name;
-
-        if (!drv)
-                return;
-
-        sysfs_remove_link(&drv->kobj, "module");
-
-        if (drv->owner)
-                mk = &drv->owner->mkobj;
-        else if (drv->mkobj)
-                mk = drv->mkobj;
-        if (mk && mk->drivers_dir) {
-                driver_name = make_driver_name(drv);
-                if (driver_name) {
-                        sysfs_remove_link(mk->drivers_dir, driver_name);
-                        kfree(driver_name);
-                }
-        }
-}
-EXPORT_SYMBOL(module_remove_driver);
-#endif
-
 #ifdef CONFIG_MODVERSIONS
 /* Generate the signature for struct module here, too, for modversions. */
 void struct_module(struct module *mod) { return; }