Commit d5582854 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

PCI/MSI: Unbreak pci_irq_get_affinity() 



The recent cleanup of pci_irq_get_affinity() broke the function for
PCI/MSI-X and indices > 0. Only the MSI descriptor for PCI/MSI has more
than one affinity mask which can be retrieved via the MSI index.

PCI/MSI-X has one descriptor per vector and each has a single affinity
mask.

Use index 0 when accessing the affinity mask in the MSI descriptor when
MSI-X is enabled.

Fixes: f4823590 ("PCI/MSI: Simplify pci_irq_get_affinity()")
Reported-by: default avatarNathan Chancellor <nathan@kernel.org>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Tested-by: default avatarNathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/87v8zm9pmd.ffs@tglx
parent cd6cf065

drivers/pci/msi/msi.c

+8 −2
Original line number Diff line number Diff line
@@ -1100,7 +1100,7 @@ EXPORT_SYMBOL(pci_irq_vector); 
 */

const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)

{

	int irq = pci_irq_vector(dev, nr);

	int idx, irq = pci_irq_vector(dev, nr);

	struct msi_desc *desc;



	if (WARN_ON_ONCE(irq <= 0))
@@ -1113,7 +1113,13 @@ const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr) 


	if (WARN_ON_ONCE(!desc->affinity))

		return NULL;

	return &desc->affinity[nr].mask;



	/*

	 * MSI has a mask array in the descriptor.

	 * MSI-X has a single mask.

	 */

	idx = dev->msi_enabled ? nr : 0;

	return &desc->affinity[idx].mask;

}

EXPORT_SYMBOL(pci_irq_get_affinity);