ChangeSet 1.1608.84.2, 2004/03/10 16:04:33-08:00, chrisw@osdl.org [PATCH] Patch to hook up PPP to simple class sysfs support * Hanna Linder (hannal@us.ibm.com) wrote: > + ppp_class = class_simple_create(THIS_MODULE, "ppp"); > + class_simple_device_add(ppp_class, MKDEV(PPP_MAJOR, 0), NULL, "ppp"); What happens if that class_simple_create() fails? Actually, class_simple_device_add could fail too, but doesn't seem anybody is checking for that. > err = devfs_mk_cdev(MKDEV(PPP_MAJOR, 0), > S_IFCHR|S_IRUSR|S_IWUSR, "ppp"); > - if (err) > + if (err) { > unregister_chrdev(PPP_MAJOR, "ppp"); > + class_simple_device_remove(MKDEV(PPP_MAJOR,0)); > + } need to destroy the class on error path to avoid leak. > @@ -2540,6 +2547,7 @@ static void __exit ppp_cleanup(void) > if (unregister_chrdev(PPP_MAJOR, "ppp") != 0) > printk(KERN_ERR "PPP: failed to unregister PPP device\n"); > devfs_remove("ppp"); > + class_simple_device_remove(MKDEV(PPP_MAJOR, 0)); ditto. this will leak and would cause oops on reload of module. something like below. drivers/net/ppp_generic.c | 21 ++++++++++++++++++++- 1 files changed, 20 insertions(+), 1 deletion(-) diff -Nru a/drivers/net/ppp_generic.c b/drivers/net/ppp_generic.c --- a/drivers/net/ppp_generic.c Mon Mar 15 15:30:17 2004 +++ b/drivers/net/ppp_generic.c Mon Mar 15 15:30:17 2004 @@ -45,6 +45,7 @@ #include #include #include +#include #include #include @@ -271,6 +272,8 @@ static int ppp_disconnect_channel(struct channel *pch); static void ppp_destroy_channel(struct channel *pch); +static struct class_simple *ppp_class; + /* Translates a PPP protocol number to a NP index (NP == network protocol) */ static inline int proto_to_npindex(int proto) { @@ -804,15 +807,29 @@ printk(KERN_INFO "PPP generic driver version " PPP_VERSION "\n"); err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops); if (!err) { + ppp_class = class_simple_create(THIS_MODULE, "ppp"); + if (IS_ERR(ppp_class)) { + err = PTR_ERR(ppp_class); + goto out_chrdev; + } + class_simple_device_add(ppp_class, MKDEV(PPP_MAJOR, 0), NULL, "ppp"); err = devfs_mk_cdev(MKDEV(PPP_MAJOR, 0), S_IFCHR|S_IRUSR|S_IWUSR, "ppp"); if (err) - unregister_chrdev(PPP_MAJOR, "ppp"); + goto out_class; } +out: if (err) printk(KERN_ERR "failed to register PPP device (%d)\n", err); return err; + +out_class: + class_simple_device_remove(MKDEV(PPP_MAJOR,0)); + class_simple_destroy(ppp_class); +out_chrdev: + unregister_chrdev(PPP_MAJOR, "ppp"); + goto out; } /* @@ -2545,6 +2562,8 @@ if (unregister_chrdev(PPP_MAJOR, "ppp") != 0) printk(KERN_ERR "PPP: failed to unregister PPP device\n"); devfs_remove("ppp"); + class_simple_device_remove(MKDEV(PPP_MAJOR, 0)); + class_simple_destroy(ppp_class); } /*