On Tue, Dec 20, 2016 at 05:49:33PM +1100, Gavin Shan wrote: > The surprise hotplug is driven by interrupt in PowerNV PCI hotplug > driver. In the interrupt handler, pnv_php_interrupt(), we bail when > pnv_pci_get_presence_state() returns zero wrongly. It causes the > presence change event is always ignored incorrectly. > > This fixes the issue by bailing on error (non-zero value) returned > from pnv_pci_get_presence_state(). > > Fixes: 360aebd85a4 ("drivers/pci/hotplug: Support surprise hotplug in powernv > driver") > Cc: sta...@vger.kernel.org #v4.9+ > Reported-by: Hank Chang <hankmax0...@gmail.com> > Signed-off-by: Gavin Shan <gws...@linux.vnet.ibm.com> > Tested-by: Willie Liauw <will...@supermicro.com.tw> > --- > drivers/pci/hotplug/pnv_php.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c > index 56efaf7..38a2309 100644 > --- a/drivers/pci/hotplug/pnv_php.c > +++ b/drivers/pci/hotplug/pnv_php.c > @@ -707,8 +707,12 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data) > added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); > } else if (sts & PCI_EXP_SLTSTA_PDC) { > ret = pnv_pci_get_presence_state(php_slot->id, &presence); > - if (!ret) > + if (ret) { > + dev_warn(&pdev->dev, "PCI slot [%s] error %d handling > PDC event (0x%04x)\n", > + php_slot->name, ret, sts);
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