On 10/31, Tejun Heo wrote: > > Commit 27920651fe "PM / Freezer: Make fake_signal_wake_up() wake > TASK_KILLABLE tasks too" made freezer wake up tasks in TASK_KILLABLE > sleep too citing non-interruptible but killable sleeps in cifs and > nfs. > > I don't think we can do this. We should not send spurious unsolicited > non-interruptible wakeups. Most synchornization constructs are built > to cope with spurious wakeups and any INTERRUPTIBLE sleep must be able > to handle spurious wakeups but that's not true for KILLABLE sleeps - > KILLABLE condition cannot be cancelled.
Agreed. For example. sys_read() or page can sleep in TASK_KILLABLE assuming that wait/down/whatever _killable can only fail if we can not return to the usermode. TASK_TRACED case is obviously wrong too. > --- a/kernel/freezer.c > +++ b/kernel/freezer.c > @@ -67,7 +67,7 @@ static void fake_signal_wake_up(struct task_struct *p) > unsigned long flags; > > spin_lock_irqsave(&p->sighand->siglock, flags); > - signal_wake_up(p, 1); > + signal_wake_up(p, 0); > spin_unlock_irqrestore(&p->sighand->siglock, flags); > } Agreed, this looks like a bug fix to me. Acked-by: Oleg Nesterov <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
