Commit 1afe7b4a authored Jan 11, 2017 by Gavin Shan Committed by Greg Kroah-Hartman Mar 15, 2017

drivers/pci/hotplug: Handle presence detection change properly



commit d7d55536c6cd1f80295b6d7483ad0587b148bde4 upstream.

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")
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 17ea11d5

drivers/pci/hotplug/pnv_php.c

+5 −1

Original line number	Diff line number	Diff line
		@@ -713,8 +713,12 @@ 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 getting presence (0x%04x), to retry the operation.\n",
		php_slot->name, ret, sts);
		return IRQ_HANDLED;
		}

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