diff options
| author | Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> | 2014-11-10 09:27:29 +1030 |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2014-11-11 17:07:45 +1030 |
| commit | 461e34aed0550fee706a9a28fb453830b5079ea0 (patch) | |
| tree | 6a0a337bc67f6c1347866a7feceebfcf135cfcc2 | |
| parent | 4f48795b6154852d07d971e402c35ecc460ddcb6 (diff) | |
module: Unlink module with RCU synchronizing instead of stop_machine
Unlink module from module list with RCU synchronizing instead
of using stop_machine(). Since module list is already protected
by rcu, we don't need stop_machine() anymore.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| -rw-r--r-- | kernel/module.c | 18 |
1 files changed, 5 insertions, 13 deletions
diff --git a/kernel/module.c b/kernel/module.c index 331b03f6b411..bed608b8c8a6 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1697,18 +1697,6 @@ static void mod_sysfs_teardown(struct module *mod) mod_sysfs_fini(mod); } -/* - * unlink the module with the whole machine is stopped with interrupts off - * - this defends against kallsyms not taking locks - */ -static int __unlink_module(void *_mod) -{ - struct module *mod = _mod; - list_del(&mod->list); - module_bug_cleanup(mod); - return 0; -} - #ifdef CONFIG_DEBUG_SET_MODULE_RONX /* * LKM RO/NX protection: protect module's text/ro-data @@ -1860,7 +1848,11 @@ static void free_module(struct module *mod) /* Now we can delete it from the lists */ mutex_lock(&module_mutex); - stop_machine(__unlink_module, mod, NULL); + /* Unlink carefully: kallsyms could be walking list. */ + list_del_rcu(&mod->list); + /* Wait for RCU synchronizing before releasing mod->list. */ + synchronize_rcu(); + module_bug_cleanup(mod); mutex_unlock(&module_mutex); /* This may be NULL, but that's OK */ |