PCI/MSI: Check that we have a legacy interrupt line before using it

It seems like there are some devices (e.g. the PCIe root port driver) that
may not always have a INTx interrupt.  Check for dev->irq before returning
a legacy interrupt in pci_irq_alloc_vectors to properly handle this case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Christoph Hellwig 2017-02-01 14:41:42 +01:00 committed by Bjorn Helgaas
parent 699c4cec23
commit 862290f9e2

View File

@ -1198,9 +1198,11 @@ int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
}
/* use legacy irq if allowed */
if ((flags & PCI_IRQ_LEGACY) && min_vecs == 1) {
pci_intx(dev, 1);
return 1;
if (flags & PCI_IRQ_LEGACY) {
if (min_vecs == 1 && dev->irq) {
pci_intx(dev, 1);
return 1;
}
}
return vecs;