lkml.org 
[lkml]   [2010]   [Mar]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] move tty_kref_put() outside of __cleanup_signal()
> This task is new, nobody can see/use it before we drop the locks. NULL or not,
> its signal->tty is just uninitialized yet.

Fair enough.

>
> > > --- 34-rc1/kernel/exit.c~7_TTY_PUT 2010-03-17 20:05:38.000000000 +0100
> > > +++ 34-rc1/kernel/exit.c 2010-03-18 22:46:41.000000000 +0100
> > > @@ -150,6 +150,7 @@ static void __exit_signal(struct task_st
> > > * see account_group_exec_runtime().
> > > */
> > > task_rq_unlock_wait(tsk);
> > > + tty_kref_put(sig->tty);
> >
> > and a sig->tty = NULL assignment to trap races might not go amiss here
> > perhaps ?
>
> Indeed ;)
>
> The subsequent patches will do this, we need more changes anyway. Currently
> this doesn't matter because we are going to kfree() this memory unconditionally.
> But when we pin ->signal to task_struct, we should clear ->signal->tty before
> we drop ->siglock, then tty_kref_put().

Ok - yes the moment you start refcounting ->signal that changes (or do you
expect to free ->tty when you destruct the signals ?)


\
 
 \ /
  Last update: 2010-03-19 12:07    [from the cache]
©2003-2011 Jasper Spaans