Re: [PATCH v2] [media] rc: ite-cir: Initialise ite_dev::rdev earlier

[Luis Henriques <luis.henriques@canonical.com>]

On Tue, Aug 28, 2012 at 10:09:55AM -0700, Ben Hutchings wrote:
> On Tue, 2012-08-28 at 12:44 +0100, Luis Henriques wrote:
> > On Mon, Aug 20, 2012 at 12:32:27AM +0100, Ben Hutchings wrote:
> > > ite_dev::rdev is currently initialised in ite_probe() after
> > > rc_register_device() returns.  If a newly registered device is opened
> > > quickly enough, we may enable interrupts and try to use ite_dev::rdev
> > > before it has been initialised.  Move it up to the earliest point we
> > > can, right after calling rc_allocate_device().
> > 
> > I believe this is the same bug:
> > 
> > https://bugzilla.kernel.org/show_bug.cgi?id=46391
> > 
> > And the bug is present in other IR devices as well.
> > 
> > I've sent a proposed fix:
> > 
> > http://marc.info/?l=linux-kernel&m=134590803109050&w=2
> 
> It might be a worthwhile fix.  But it doesn't fix this bug - after that
> patch, the driver will still enable its IRQ before initialising
> ite_dev::rdev.

You're absolutely right, sorry for the noise.  I should have taken a
closer look at your patch.

Cheers,
--
Luis

> 
> Ben.
> 
> > Cheers,
> > --
> > Luis
> > 
> > > 
> > > References: http://bugs.debian.org/684441 Reported-and-tested-by:
> > > YunQiang Su <wzssyqa@gmail.com> Signed-off-by: Ben Hutchings
> > > <ben@decadent.org.uk> Cc: stable@vger.kernel.org --- Unlike the
> > > previous version, this will apply cleanly to the media
> > > staging/for_v3.6 branch.
> > > 
> > > Ben.
> > > 
> > >  drivers/media/rc/ite-cir.c |    2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/media/rc/ite-cir.c b/drivers/media/rc/ite-cir.c
> > > index 36fe5a3..24c77a4 100644
> > > --- a/drivers/media/rc/ite-cir.c
> > > +++ b/drivers/media/rc/ite-cir.c
> > > @@ -1473,6 +1473,7 @@ static int ite_probe(struct pnp_dev *pdev, const struct pnp_device_id
> > >  	rdev = rc_allocate_device();
> > >  	if (!rdev)
> > >  		goto failure;
> > > +	itdev->rdev = rdev;
> > >  
> > >  	ret = -ENODEV;
> > >  
> > > @@ -1604,7 +1605,6 @@ static int ite_probe(struct pnp_dev *pdev, const struct pnp_device_id
> > >  	if (ret)
> > >  		goto failure3;
> > >  
> > > -	itdev->rdev = rdev;
> > >  	ite_pr(KERN_NOTICE, "driver has been successfully loaded\n");
> > >  
> > >  	return 0;
> > > 
> > 
> 
> -- 
> Ben Hutchings
> It is a miracle that curiosity survives formal education. - Albert Einstein