Re: [PATCH/RFC] signal races/bugs, losing TIF_SIGPENDING and otherwoes

From: Davide Libenzi
Date: Tue Jun 05 2007 - 20:11:57 EST


On Wed, 6 Jun 2007, Benjamin Herrenschmidt wrote:

> On Tue, 2007-06-05 at 15:50 -0700, Davide Libenzi wrote:
> > > What about the code in __dequeue_signal though ? That notifier thing
> > is
> > > used by the DRI though I'm not sure what would happen if it acts on
> > the
> > > wrong task.
> >
> > Hmm, looking at the comments in block_all_signals(), it seems that
> > they're
> > interested in the fact that a specific task dequeue the signal. So,
> > at
> > a first sight, it seems that such code should not not be executed if
> > another task dequeue the message. What do you think?
>
> Yes, I think the idea is that the DRM uses that to prevent signals to be
> delivered to the task that is blocking them with the notifier (I have no
> idea why they can't use the normal block mecanism for that... looks like
> a hack to me).
>
> So I suppose it's fine, as long as you add a test of tsk == current to
> avoid calling it.

Are you going patchwise, or should I do it?


- Davide


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