Re: [PATCH v11 8/9] vfio: Add a reset_done callback for vfio-pci driver

[Alex Williamson <alex@shazbot.org>]

On Mon, 16 Mar 2026 12:15:43 -0700
Farhan Ali <alifm@linux.ibm.com> wrote:

> On error recovery for a PCI device bound to vfio-pci driver, we want to
> recover the state of the device to its last known saved state. The callback
> restores the state of the device to its initial saved state.
> 
> Reviewed-by: Julian Ruess <julianr@linux.ibm.com>
> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
> Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
> ---
>  drivers/vfio/pci/vfio_pci_core.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
> index bbdb625e35ef..f1bd1266b88f 100644
> --- a/drivers/vfio/pci/vfio_pci_core.c
> +++ b/drivers/vfio/pci/vfio_pci_core.c
> @@ -2257,6 +2257,17 @@ pci_ers_result_t vfio_pci_core_aer_err_detected(struct pci_dev *pdev,
>  }
>  EXPORT_SYMBOL_GPL(vfio_pci_core_aer_err_detected);
>  
> +static void vfio_pci_core_aer_reset_done(struct pci_dev *pdev)
> +{
> +	struct vfio_pci_core_device *vdev = dev_get_drvdata(&pdev->dev);
> +
> +	if (!vdev->pci_saved_state)
> +		return;
> +
> +	pci_load_saved_state(pdev, vdev->pci_saved_state);
> +	pci_restore_state(pdev);
> +}
> +
>  int vfio_pci_core_sriov_configure(struct vfio_pci_core_device *vdev,
>  				  int nr_virtfn)
>  {
> @@ -2321,6 +2332,7 @@ EXPORT_SYMBOL_GPL(vfio_pci_core_sriov_configure);
>  
>  const struct pci_error_handlers vfio_pci_core_err_handlers = {
>  	.error_detected = vfio_pci_core_aer_err_detected,
> +	.reset_done = vfio_pci_core_aer_reset_done,
>  };
>  EXPORT_SYMBOL_GPL(vfio_pci_core_err_handlers);
>  

It gives me some anxiety to restore the open state of the device here,
but I can't identify any specific issues.  We'll try it and see how it
goes.

Acked-by: Alex Williamson <alex@shazbot.org>

Thanks,
Alex