Re: [PATCH 04/10] PCI: pciehp: Do not handle events if interrupts are masked

[Mika Westerberg <mika.westerberg@linux.intel.com>]

On Sat, Sep 08, 2018 at 08:16:17AM +0200, Lukas Wunner wrote:
> On Fri, Sep 07, 2018 at 04:45:46PM -0600, Keith Busch wrote:
> > On Thu, Sep 06, 2018 at 06:50:14PM +0300, Mika Westerberg wrote:
> > > PCIe native hotplug shares MSI vector with native PME so the interrupt
> > > handler might get called even the hotplug interrupt is masked. In that
> > > case we should not handle any events because the interrupt was not meant
> > > for us. Modify the PCIe hotplug interrupt handler to check this
> > > accordingly and bail out if it finds out that the interrupt was not
> > > about hotplug.
> > > 
> > > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> > > ---
> > >  drivers/pci/hotplug/pciehp_hpc.c | 6 ++++--
> > >  1 file changed, 4 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
> > > index 2249c4d06efd..19ed13d44b8f 100644
> > > --- a/drivers/pci/hotplug/pciehp_hpc.c
> > > +++ b/drivers/pci/hotplug/pciehp_hpc.c
> > > @@ -533,9 +533,11 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id)
> > >  	u16 status, events;
> > >  
> > >  	/*
> > > -	 * Interrupts only occur in D3hot or shallower (PCIe r4.0, sec 6.7.3.4).
> > > +	 * Interrupts only occur in D3hot or shallower and only if enabled
> > > +	 * in the Slot Control register (PCIe r4.0, sec 6.7.3.4).
> > >  	 */
> > > -	if (pdev->current_state == PCI_D3cold)
> > > +	if (pdev->current_state == PCI_D3cold ||
> > > +	    !(ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE))
> > >  		return IRQ_NONE;
> > >  
> > >  	/*
> > 
> > Isn't this going to break pciehp_poll_mode?
> 
> Excellent catch, you're right, it needs to be constrained to
> !pciehp_poll_mode.

OK, I'll add the check to v2.