Re: [PATCH] vhost: Unbreak SMMU and virtio-iommu on dev-iotlb support

[Peter Xu]

On Tue, Feb 09, 2021 at 06:15:11PM +0100, Auger Eric wrote:
> I just noted that the vhost fix now breaks virtio-iommu/vfio integration
> because VFIO registers IOMMU_NOTIFIER_ALL which includes the DEV-IOTLB
> that is now rejected by virtio-iommu virtio_iommu_notify_flag_changed().
> Is it safe to replace IOMMU_NOTIFIER_ALL by IOMMU_NOTIFIER_IOTLB_EVENTS
> in vfio_listener_region_add (hw/vfio/common.c) or shall we also do the
> 2-step registration? After your confirmation, I can send the patch.

Thanks for noticing this, Eric.  Indeed there're a bunch of things that we'd
overlooked.

I think IOMMU_NOTIFIER_IOTLB_EVENTS should suffice with vfio.

If you post that patch, would you mind post a similar fix for PPC too which
will need the two-step thing?  Assuming they can be in the same series to fix
the breakage of that same patch.

CC Alex and David Gibson.

Thanks,

-- 
Peter Xu