Re: [PATCH net 1/1] net: stmmac: disable Split Header (SPH) for Intel platforms

[Paolo Abeni]

Hello,

On Thu, 2022-04-28 at 09:55 +0800, Tan Tee Min wrote:
> On Tue, Apr 26, 2022 at 03:58:56PM +0200, Kurt Kanzenbach wrote:
> > Hi,
> > 
> > On Tue Apr 26 2022, Tan Tee Min wrote:
> > > Based on DesignWare Ethernet QoS datasheet, we are seeing the limitation
> > > of Split Header (SPH) feature is not supported for Ipv4 fragmented packet.
> > > This SPH limitation will cause ping failure when the packets size exceed
> > > the MTU size. For example, the issue happens once the basic ping packet
> > > size is larger than the configured MTU size and the data is lost inside
> > > the fragmented packet, replaced by zeros/corrupted values, and leads to
> > > ping fail.
> > > 
> > > So, disable the Split Header for Intel platforms.
> > 
> > Does this issue only apply on Intel platforms?
> 
> According to Synopsys IP support, they have confirmed the header-payload
> splitting for IPv4 fragmented packets is not supported for the Synopsys
> Ether IPs.
> 
> Intel platforms are integrating with GMAC EQoS IP which is impacted by the
> limitation above, so we are changing the default SPH setting to disabled
> for Intel Platforms only.
> 
> If anyone can confirm on their platform also having the same issues,
> then we would change the SPH default to disable across the IPs.

Could you please provide a Fixes tag here? 

Thanks!

Paolo