Re: [PATCH v6 10/11] vfio/pci: Add dma-buf export support for MMIO regions

[Alex Williamson <alex@shazbot.org>]

On Sun,  2 Nov 2025 10:00:58 +0200
Leon Romanovsky <leon@kernel.org> wrote:
> @@ -2391,6 +2403,7 @@ static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set,
>  				      struct iommufd_ctx *iommufd_ctx)
>  {
>  	struct vfio_pci_core_device *vdev;
> +	bool restore_revoke = false;
>  	struct pci_dev *pdev;
>  	int ret;
>  
> @@ -2459,6 +2472,8 @@ static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set,
>  			break;
>  		}
>  
> +		vfio_pci_dma_buf_move(vdev, true);
> +		restore_revoke = true;
>  		vfio_pci_zap_bars(vdev);
>  	}
>  
> @@ -2486,6 +2501,12 @@ static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set,
>  			       struct vfio_pci_core_device, vdev.dev_set_list);
>  
>  err_undo:
> +	if (restore_revoke) {
> +		list_for_each_entry(vdev, &dev_set->device_list, vdev.dev_set_list)
> +			if (__vfio_pci_memory_enabled(vdev))
> +				vfio_pci_dma_buf_move(vdev, false);
> +	}
> +
>  	list_for_each_entry_from_reverse(vdev, &dev_set->device_list,
>  					 vdev.dev_set_list)

We don't need the separate loop or flag, and adding it breaks the
existing reverse list walk.  Thanks,

Alex