Re: [PATCH v2 4/4] virtio-net: Add support for USO features
On 2024/08/05 16:30, Michael S. Tsirkin wrote:
On Sun, Aug 04, 2024 at 03:49:45PM +0900, Akihiko Odaki wrote:
> I suggest disabling all offload features of virtio-net with 9.2.
Yea ... no.
> I want to keep things consistent so I want to disable all at once. This
> change will be very uncomfortable for us, who are implementing offload
> features, but I hope it will motivate us to implement a proper solution.
It's uncomfortable for users.
An obvious alternative is to set cross-migrate=off by default (I dropped
the no- prefix because no-cross-migrate=off is confusing). I don't have
a particular idea whether cross-migrate should be on or off by default.
This is a trade-off of safety and performance. In general, I believe
safety should come first before performance.
On the other hand, disabling offload features is a breaking change. QEMU
also has -only-migratable option; it is more consistent to make the
additional assurance for migration opt-in instead of opt-out. Finally, I
see migration across hosts as an advanced feature, and perhaps it can be
justified to make it more like an optional feature.
Regards,
Akihiko Odaki