On Fri, 27 Mar 2026 11:22:43 +0800 Jason Wang wrote:

On Fri, Mar 27, 2026 at 11:03 AM Jakub Kicinski [off-list ref] wrote:

quoted

On Mon, 23 Mar 2026 12:17:30 +0800 Di Zhu wrote:  

quoted

Negotiating VIRTIO_NET_F_CTRL_GUEST_OFFLOADS indicates the device
allows control over offload support, but the offloads that can be
controlled may have nothing to do with GRO (e.g., if neither GUEST_TSO4
nor GUEST_TSO6 is supported).

In such a setup, reporting NETIF_F_GRO_HW as available for the device
is too optimistic and misleading to the user.

Improve the situation by masking off NETIF_F_GRO_HW unless the device
possesses actual GRO-related offload capabilities. Out of an abundance
of caution, this does not change the current behaviour for hardware with
just v6 or just v4 GRO: current interfaces do not allow distinguishing
between v6/v4 GRO, so we can't expose them to userspace precisely.  

Michael, Jason, does this patch look good now?

https://lore.kernel.org/all/20260323041730.986351-1-zhud@hygon.cn/ (local)
 

Yes, I've acked.

Obrigado!