On Wed, Aug 02, 2017 at 01:24:58PM -0500, Bjorn Helgaas wrote:
> On Wed, Jul 26, 2017 at 10:17:41PM +0200, Christoph Hellwig wrote:
> > We'll always get NULL back in that case, so skip the call and the
> > resulting warning.
> ...
> 2. The patch makes sense in that if we're only allocating a single
> vector, there's nothing to spread around and there's no need to
> allocate a cpumask. But I haven't figured out why we get a warning.
> I assume it's because we're getting NULL back when we call
> irq_create_affinity_masks() with nvecs==1, but that only happens if
> affv==0 or the zalloc fails, and I don't see why either would be the
> case.
Waiting for clarification on this question...
> > Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> > ---
> > 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 253d92409bb3..19653e5cb68f 100644
> > --- a/drivers/pci/msi.c
> > +++ b/drivers/pci/msi.c
> > @@ -538,7 +538,7 @@ msi_setup_entry(struct pci_dev *dev, int nvec, const struct irq_affinity *affd)
> > struct msi_desc *entry;
> > u16 control;
> >
> > - if (affd) {
> > + if (affd && nvec > 1) {
> > masks = irq_create_affinity_masks(nvec, affd);
> > if (!masks)
> > dev_err(&dev->dev, "can't allocate MSI affinity masks for %d vectors\n",
> > @@ -679,7 +679,7 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
> > struct msi_desc *entry;
> > int ret, i;
> >
> > - if (affd) {
> > + if (affd && nvec > 1) {
> > masks = irq_create_affinity_masks(nvec, affd);
> > if (!masks)
> > dev_err(&dev->dev, "can't allocate MSI-X affinity masks for %d vectors\n",
> > --
> > 2.11.0
> >
