Re: [PATCH 1/1] vfio iommu type1: WARN_ON if notifier block is not unregistered

From: Alex Williamson
Date: Mon Dec 05 2016 - 18:26:18 EST


On Tue, 6 Dec 2016 02:38:20 +0530
Kirti Wankhede <kwankhede@xxxxxxxxxx> wrote:

> mdev vendor driver should unregister the iommu notifier since the vfio
> iommu can persist beyond the attachment of the mdev group. WARN_ON will
> show warning if vendor driver doesn't unregister the notifier and is
> forced to follow the implementations steps.
>
> Signed-off-by: Kirti Wankhede <kwankhede@xxxxxxxxxx>
> Signed-off-by: Neo Jia <cjia@xxxxxxxxxx>
> Change-Id: I75fd0a40e582a144fe7a037c7140d3513e8ff030
> ---
> drivers/vfio/vfio_iommu_type1.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 023fba7b8d5a..37871ee0c0c5 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -1361,6 +1361,8 @@ static void vfio_sanity_check_pfn_list(struct vfio_iommu *iommu)
> if (WARN_ON(!RB_EMPTY_ROOT(&dma->pfn_list)))
> break;
> }
> + /* mdev venfor driver must unregister notifier */

s/venfor/vendor/

> + WARN_ON(iommu->notifier.head);
> }
>
> static void vfio_iommu_type1_detach_group(void *iommu_data,

Applied for v4.10 with the above typo fix. Thanks,

Alex