RE: [PATCH v11 2/4] virtio-net: clarify DATA_VALID semantic for encap protos.

Parav Pandit
2025-01-19T07:57:06Z

> From: Paolo Abeni <pabeni@redhat.com>
> Sent: Wednesday, November 27, 2024 3:07 PM

> DATA_VALID allows offloading a single checksum level, leaving unspecified
> which header checksum is offloaded when one or more encapsulated
> protocols are present.
>
> In such a case, the only option usable from the guest OS is offloading the
> outermost checksum. That also matches the existing implementation.
>
> Explicitly state such the constraint, to remove any ambiguity and make later
> changes more straightforward.
>
> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
> ---
> device-types/net/description.tex | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/device-types/net/description.tex b/device-
> types/net/description.tex
> index 3434a31..77bd847 100644
> --- a/device-types/net/description.tex
> +++ b/device-types/net/description.tex
> @@ -994,8 +994,8 @@ \subsubsection{Processing of Incoming
> Packets}\label{sec:Device Types / Network If the
> VIRTIO_NET_F_GUEST_CSUM feature has been negotiated, the device MAY
> set the VIRTIO_NET_HDR_F_DATA_VALID bit in \field{flags}, if so, the device
> MUST validate the packet -checksum (in case of multiple encapsulated
> protocols, one level -of checksums is validated).
> +checksum. One level of checksum is validated: in case of multiple
> +encapsulated protocols the outermost one.
>
> \drivernormative{\paragraph}{Processing of Incoming Packets}{Device Types
> / Network Device / Device Operation /
> --
> 2.45.2
>

Reviewed-by: Parav Pandit <parav@nvidia.com>