Dmitry Torokhov, on 11/15/2010 10:04 AM wrote: >> 1. What to do if another SCST object is being created with the same name >> as supposed to be deleted, but not completely dead yet? > > The same rules as with files - the object disappears from the > "directories" so no new users can get it but is not destroyed till last > reference is gone. > >> >> 2. What to do if a dieing object is found on some list and reference for >> is supposed to be taken? If the object deleted from the list before it >> marked dieing, i.e. the latest internal put() done, it made additional >> problems during deleting it after the latest external put done. > > You delete the object from the list, then mark it as dead, notify users, > drop refcount. No new users will get it (as it is not on the list > anymore) and existing ones should notice that it is dead and stop using > it. Those are good in theory, but on practice, you know, devil is in the details.. >> This is because SYSFS doesn't hold references for the corresponding >> kobjects for every open file handle. It holds references only when >> show() and store() functions called. So, everything is under control and >> a malicious user can do nothing to hold a reference forever. > > Right, Tejun plugged this particular (and very annoying) attributes > behavior This behavior isn't annoying, it's GREAT, because it allows to use SYSFS simply and reliably. >, but that does not mean that this is the only way kobject's > reference might be pinned. Could you be more specific and point out on exact ways for that? From my quite deep SYSFS source code study I see such cases should not exist. Thanks, Vlad -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
