Hello,
During debug I faced oops in
netdev_unregister_sysfs()->sysfs_remove_group(),
since kobj->dentry == NULL.
The problem is that netdev code doesn't handle errors from sysfs
correctly - it calls netdev_unregister_sysfs() in any case, even if
netdev_register_sysfs() failed on registering:
void netdev_run_todo(void)
...
case NETREG_REGISTERING:
err = netdev_register_sysfs(dev);
if (err)
printk(KERN_ERR "%s: failed sysfs
registration (%d)\n",
dev->name, err);
dev->reg_state = NETREG_REGISTERED;
break;
case NETREG_UNREGISTERING:
netdev_unregister_sysfs(dev); <<<< OOPS here,
<<<< if netdev_register_sysfs()
<<<<< failed
...
I tried to fix it in netdev code, but it's impossible to do it in a
fashioned manner. Since there are some kobject manipulations in
destructors (e.g. free_netdev() oopses as well if workaround the above
code).
Another approach can be to check kobj->dentry and other fields in sysfs.
Maybe someone has any ideas on this? Except for "no errors should
normally happen" :)
Kirill