When debugging an issue where I was asking the PCI machinery to enable a set of MSIx vectors, without falling back on MSI, I ran across a behaviour which seems odd. The pci_alloc_irq_vectors_affinity will always return -ENOSPC on failure, when allocating MSIx vectors only, whereas with MSI fallback it will forward any error returned by __pci_enable_msi_range. This is a confusing behaviour, so have the pci_alloc_irq_vectors_affinity forward the error code from __pci_enable_msix_range when appropriate. Signed-off-by: Piotr Stankiewicz <piotr.stankiewicz@xxxxxxxxx> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> --- drivers/pci/msi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 6b43a5455c7a..9db9ce5dddb3 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -1231,8 +1231,8 @@ int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs, } } - if (msix_vecs == -ENOSPC) - return -ENOSPC; + if (msix_vecs == -ENOSPC || (flags & PCI_IRQ_MSI_TYPES) == PCI_IRQ_MSIX) + return msix_vecs; return msi_vecs; } EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity); -- 2.17.2
