PCI/msi: fix the pci_alloc_irq_vectors_affinity stub

We need to return an error for any call that asks for MSI / MSI-X
vectors only, so that non-trivial fallback logic can work properly.

Also valid dev->irq and use the "correct" errno value based on feedback
from Linus.

Signed-off-by: Christoph Hellwig <[email protected]>
Reported-by: Steven Rostedt <[email protected]>
Fixes: aff17164 ("PCI: Provide sensible IRQ vector alloc/free routines")
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 33c2b0b77429d09aaa31cb9735458db5762e08a7..fc2e832d7b9ccf3350ee75a0d35a60e3b289b69f 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1342,9 +1342,9 @@ pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
                               unsigned int max_vecs, unsigned int flags,
                               const struct irq_affinity *aff_desc)
 {
-       if (min_vecs > 1)
-               return -EINVAL;
-       return 1;
+       if ((flags & PCI_IRQ_LEGACY) && min_vecs == 1 && dev->irq)
+               return 1;
+       return -ENOSPC;
 }
 
 static inline void pci_free_irq_vectors(struct pci_dev *dev)