Re: 3.12: kernel panic when resuming from suspend to RAM (x86_64)

Thomas Gleixner
2013-12-02T11:20:51Z

On Mon, 2 Dec 2013, Thomas Gleixner wrote:
> On Sat, 30 Nov 2013, Francis Moreau wrote:
> > Hello Thomas,
> >
> > Sorry for the delay.
> >
> > On 11/29/2013 10:02 AM, Thomas Gleixner wrote:
> > > On Fri, 29 Nov 2013, Francis Moreau wrote:
> > >> Since it seems to be related to rtsx driver or its upper layer, could
> > >> the folks involved in this area have a look to this issue please ?
> > >
> > > I'm not involved, but looking at the debug objects backtrace it's
> > > related to the delayed work in rtsx.
> > >
> > > Does the untested patch below cure the issue?
> > >
> >
> > It seems it does since I can't see the debug object trace anymore
> > however Ican see this now:
>
> <SNIP>
>
> > So I don't think it completely solve the problem but it's a good start.
>
> I kinda expected that, but I wanted to confirm my suspicion, that the
> interrupt hits after the delayed work is canceled and just requeues it
> again, which then leads to an armed timer being freed further down.
>
> I'm not familiar with that driver and I leave the final fixup to the
> driver maintainers. It's enough data for them to figure out the real
> solution.

Just had a quick look and the obvious solution is to disable the
interrupts at the device level _BEFORE_ doing anything else in the
teardown path. Updated patch below. That should avoid the nobody cared
splat on the other irq line.

Thanks,

tglx

Index: linux-2.6/drivers/mfd/rtsx_pcr.c
===================================================================
--- linux-2.6.orig/drivers/mfd/rtsx_pcr.c
+++ linux-2.6/drivers/mfd/rtsx_pcr.c
@@ -1228,8 +1228,14 @@ static void rtsx_pci_remove(struct pci_d

pcr->remove_pci = true;

- cancel_delayed_work(&pcr->carddet_work);
- cancel_delayed_work(&pcr->idle_work);
+ /* Disable interrupts at the pcr level */
+ spin_lock_irq(&pcr->lock);
+ rtsx_pci_writel(pcr, RTSX_BIER, 0);
+ pcr->bier = 0;
+ spin_unlock_irq(&pcr->lock);
+
+ cancel_delayed_work_sync(&pcr->carddet_work);
+ cancel_delayed_work_sync(&pcr->idle_work);

mfd_remove_devices(&pcidev->dev);