Re: [PATCH v2 1/5] iommu/s390: Make attach succeed even if the device is in error state

From: Gerd Bayer
Date: Mon Nov 14 2022 - 10:05:44 EST


Hi Niklas,

really just a nit...

On Wed, 2022-11-09 at 15:28 +0100, Niklas Schnelle wrote:
> diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c
> index 7fb512bece9a..e2c886bc4376 100644
> --- a/drivers/iommu/s390-iommu.c
> +++ b/drivers/iommu/s390-iommu.c
> @@ -98,6 +98,7 @@ static int s390_iommu_attach_device(struct iommu_domain *domain,
> struct s390_domain *s390_domain = to_s390_domain(domain);
> struct zpci_dev *zdev = to_zpci_dev(dev);
> unsigned long flags;
> + u8 status;
> int cc;
>
> if (!zdev)
> @@ -113,8 +114,12 @@ static int s390_iommu_attach_device(struct iommu_domain *domain,
> zpci_dma_exit_device(zdev);
>
> cc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
> - virt_to_phys(s390_domain->dma_table));
> - if (cc)
> + virt_to_phys(s390_domain->dma_table), &status);
> + /*
> + * If the device is undergoing error recovery the reset code
> + * will re-establish the new domain.
> + */
> + if (cc && status != ZPCI_PCI_ST_FUNC_NOT_AVAIL)
Operator precedence does "the right thing", but would a more explicit parenthesis
around (status != ZPCI_PCI_ST_FUNC_NOT_AVAIL) help or hurt here?

> return -EIO;
> zdev->dma_table = s390_domain->dma_table;

Thank you,
Gerd