Re: [PATCH v5 04/20] vfio/iommufd: Relax assert check for iommufd backend

["Cédric Le Goater" <clg@redhat.com>]

On 11/9/23 12:45, Zhenzhong Duan wrote:
> Currently iommufd doesn't support dirty page sync yet,
> but it will not block us doing live migration if VFIO
> migration is force enabled.
> 
> So in this case we allow set_dirty_page_tracking to be NULL.
> Note we don't need same change for query_dirty_bitmap because
> when dirty page sync isn't supported, query_dirty_bitmap will
> never be called.
> 
> Suggested-by: Cédric Le Goater <clg@redhat.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>

Reviewed-by: Cédric Le Goater <clg@redhat.com>

Thanks,

C.


> ---
>   hw/vfio/container-base.c | 4 ++++
>   hw/vfio/container.c      | 4 ----
>   2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/vfio/container-base.c b/hw/vfio/container-base.c
> index 71f7274973..eee2dcfe76 100644
> --- a/hw/vfio/container-base.c
> +++ b/hw/vfio/container-base.c
> @@ -55,6 +55,10 @@ void vfio_container_del_section_window(VFIOContainerBase *bcontainer,
>   int vfio_container_set_dirty_page_tracking(VFIOContainerBase *bcontainer,
>                                              bool start)
>   {
> +    if (!bcontainer->dirty_pages_supported) {
> +        return 0;
> +    }
> +
>       g_assert(bcontainer->ops->set_dirty_page_tracking);
>       return bcontainer->ops->set_dirty_page_tracking(bcontainer, start);
>   }
> diff --git a/hw/vfio/container.c b/hw/vfio/container.c
> index 6bacf38222..ed2d721b2b 100644
> --- a/hw/vfio/container.c
> +++ b/hw/vfio/container.c
> @@ -216,10 +216,6 @@ static int vfio_legacy_set_dirty_page_tracking(VFIOContainerBase *bcontainer,
>           .argsz = sizeof(dirty),
>       };
>   
> -    if (!bcontainer->dirty_pages_supported) {
> -        return 0;
> -    }
> -
>       if (start) {
>           dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_START;
>       } else {