Re: [patch V2 19/31] PCI: hv: Rework MSI handling

[Bjorn Helgaas]

On Mon, Dec 06, 2021 at 11:51:33PM +0100, Thomas Gleixner wrote:
> Replace the about to vanish iterators and make use of the filtering. Take
> the descriptor lock around the iterators.
> 
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>

> ---
>  drivers/pci/controller/pci-hyperv.c |   15 ++++++++++-----
>  1 file changed, 10 insertions(+), 5 deletions(-)
> 
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -3445,18 +3445,23 @@ static int hv_pci_suspend(struct hv_devi
>  
>  static int hv_pci_restore_msi_msg(struct pci_dev *pdev, void *arg)
>  {
> -	struct msi_desc *entry;
>  	struct irq_data *irq_data;
> +	struct msi_desc *entry;
> +	int ret = 0;
>  
> -	for_each_pci_msi_entry(entry, pdev) {
> +	msi_lock_descs(&pdev->dev);
> +	msi_for_each_desc(entry, &pdev->dev, MSI_DESC_ASSOCIATED) {
>  		irq_data = irq_get_irq_data(entry->irq);
> -		if (WARN_ON_ONCE(!irq_data))
> -			return -EINVAL;
> +		if (WARN_ON_ONCE(!irq_data)) {
> +			ret = -EINVAL;
> +			break;
> +		}
>  
>  		hv_compose_msi_msg(irq_data, &entry->msg);
>  	}
> +	msi_unlock_descs(&pdev->dev);
>  
> -	return 0;
> +	return ret;
>  }
>  
>  /*
>