Re: [PATCH v3 2/3] vfio/pci: Fix a segfault in vfio_realize

[Joao Martins <joao.m.martins@oracle.com>]

On 21/06/2023 09:02, Zhenzhong Duan wrote:
> In case irqchip_change_notifier isn't added, removing it triggers segfault.
> 
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
> ---
>  hw/vfio/pci.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index c71b0955d81c..82c4cf4f7609 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -3222,7 +3222,9 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
>  
>  out_deregister:
>      pci_device_set_intx_routing_notifier(&vdev->pdev, NULL);
> -    kvm_irqchip_remove_change_notifier(&vdev->irqchip_change_notifier);
> +    if (vdev->irqchip_change_notifier.notify) {
> +        kvm_irqchip_remove_change_notifier(&vdev->irqchip_change_notifier);
> +    }

If the first patch ends up being pursued (which I am not quite sure) it should
be folded in the previous patch, as the out_deregister is used starting your
patch 1.

>  out_teardown:
>      vfio_teardown_msi(vdev);
>      vfio_bars_exit(vdev);