Commit d7d55536 authored Jan 11, 2017 by Gavin Shan Committed by Michael Ellerman Feb 15, 2017

drivers/pci/hotplug: Handle presence detection change properly



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: 360aebd8 ("drivers/pci/hotplug: Support surprise hotplug in powernv driver")
Cc: stable@vger.kernel.org #v4.9+
Reported-by: Hank Chang <hankmax0000@gmail.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Willie Liauw <williel@supermicro.com.tw>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

parent 5b102782

drivers/pci/hotplug/pnv_php.c

+5 −1

Original line number	Original line	Diff line number	Diff line
	@@ -707,8 +707,12 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data)
	added = !!(lsts & PCI_EXP_LNKSTA_DLLLA);		added = !!(lsts & PCI_EXP_LNKSTA_DLLLA);
	} else if (sts & PCI_EXP_SLTSTA_PDC) {		} else if (sts & PCI_EXP_SLTSTA_PDC) {
	ret = pnv_pci_get_presence_state(php_slot->id, &presence);		ret = pnv_pci_get_presence_state(php_slot->id, &presence);
	if (!ret)		if (ret) {
			dev_warn(&pdev->dev, "PCI slot [%s] error %d getting presence (0x%04x), to retry the operation.\n",
			php_slot->name, ret, sts);
	return IRQ_HANDLED;		return IRQ_HANDLED;
			}

	added = !!(presence == OPAL_PCI_SLOT_PRESENT);		added = !!(presence == OPAL_PCI_SLOT_PRESENT);
	} else {		} else {
	return IRQ_NONE;		return IRQ_NONE;