Cornelia Huck wrote: > On Wed, 18 Apr 2007 03:49:01 +0900, > Tejun Heo <[EMAIL PROTECTED]> wrote: > >> Oh, one more thing, with proper code audit, we can just make >> device_unregister() do the waiting instead of adding separate >> device_unregister_wait(). I think that will be a good step toward >> immediate-detach driver model. > > Do we really want that? If the release function doesn't sit in the > module, or if the device_unregister() is done for other reasons in a > non-module, we don't care about lingering references. There's no need > to wait (and possibly lock up) there.
It's debatable but I think things will be safer this way. If we wait by default, we are forced to check that all references are dropped and will have a stack dump indicating which object is causing problem when something goes wrong, which is better than silent object leaking and/or jumping to non-existent address way later. I personally think all driver interface should be made this way such that completion of unregister function guarantees no further access to the object or module. IMHO, it's more intuitive and easier to force correctness. I'm not sure about kobject_put() but device_unregister() waiting for release doesn't sound bad to me. -- tejun - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
