Re: [patch V3 28/35] PCI/MSI: Simplify pci_irq_get_affinity()

[Nathan Chancellor]

On Sat, Dec 18, 2021 at 11:25:14AM +0100, Thomas Gleixner wrote:
> On Fri, Dec 17 2021 at 15:30, Nathan Chancellor wrote:
> > On Fri, Dec 10, 2021 at 11:19:26PM +0100, Thomas Gleixner wrote:
> > I just bisected a boot failure on my AMD test desktop to this patch as
> > commit f48235900182 ("PCI/MSI: Simplify pci_irq_get_affinity()") in
> > -next. It looks like there is a problem with the NVMe drive after this
> > change according to the logs. Given that the hard drive is not getting
> > mounted for journald to write logs to, I am not really sure how to get
> > them from the machine so I have at least taken a picture of what I see
> > on my screen; open to ideas on that front!
> 
> Bah. Fix below.

Tested-by: Nathan Chancellor <nathan@xxxxxxxxxx>

> Thanks,
> 
>         tglx
> ---
> diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
> index 71802410e2ab..9b4910befeda 100644
> --- a/drivers/pci/msi/msi.c
> +++ b/drivers/pci/msi/msi.c
> @@ -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 +1113,10 @@ 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. */
> +	idx = dev->msi_enabled ? nr : 0;
> +	return &desc->affinity[idx].mask;
>  }
>  EXPORT_SYMBOL(pci_irq_get_affinity);
>  
>