Re: [virtio-comment] Re: [PATCH v9] virtio-net: support inner header hash

[Heng Qi <hengqi@linux.alibaba.com>]

å 2023/2/28 äå7:16, Michael S. Tsirkin åé:
> On Sat, Feb 18, 2023 at 10:37:15PM +0800, Heng Qi wrote:
> > If the tunnel is used to encapsulate the packets, the hash calculated
> > using the outer header of the receive packets is always fixed for the
> > same flow packets, i.e. they will be steered to the same receive queue.
> Wait a second. How is this true? Does not everyone stick the
> inner header hash in the outer source port to solve this?
> For example geneve spec says:
>
>     it is necessary for entropy from encapsulated packets to be
>     exposed in the tunnel header.  The most common technique for this is
>     to use the UDP source port
>
> same goes for vxlan did not check further.
>
> so what is the problem?  and which tunnel types actually suffer from the
> problem?


In fact, similar to protocols such as GRE, there is no outer transport 
header.

Thanks.

>