From: Ed Swierk Date: Mon, 25 Sep 2006 23:25:36 +0000 (-0700) Subject: [PATCH] load_module: no BUG if module_subsys uninitialized X-Git-Tag: v2.6.19-rc1~1235 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1cc5f7142eca352109895fe20b1fc6405dd17727;p=linux-2.6 [PATCH] load_module: no BUG if module_subsys uninitialized Invoking load_module() before param_sysfs_init() is called crashes in mod_sysfs_setup(), since the kset in module_subsys is not initialized yet. In my case, net-pf-1 is getting modprobed as a result of hotplug trying to create a UNIX socket. Calls to hotplug begin after the topology_init initcall. Another patch for the same symptom (module_subsys-initialize-earlier.patch) moves param_sysfs_init() to the subsys initcalls, but this is still not early enough in the boot process in some cases. In particular, topology_init() causes /sbin/hotplug to run, which requests net-pf-1 (the UNIX socket protocol) which can be compiled as a module. Moving param_sysfs_init() to the postcore initcalls fixes this particular race, but there might well be other cases where a usermodehelper causes a module to load earlier still. The patch makes load_module() return an error rather than crashing the kernel if invoked before module_subsys is initialized. Cc: Mark Huang Cc: Greg KH Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/kernel/module.c b/kernel/module.c index 2a19cd47c0..b7fe6e8409 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1054,6 +1054,12 @@ static int mod_sysfs_setup(struct module *mod, { int err; + if (!module_subsys.kset.subsys) { + printk(KERN_ERR "%s: module_subsys not initialized\n", + mod->name); + 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)