Re: [PATCH iwl-next v5 1/2] ethtool: treat RXH_GTP_TEID as intrinsically symmetric

[Jakub Kicinski <kuba@kernel.org>]

On Fri, 26 Jun 2026 07:47:29 +0200 Aleksandr Loktionov wrote:
> A GTP tunnel uses the same TEID value in both directions of a flow;
> including TEID in the hash input does not break src/dst symmetry.
> 
> ethtool_rxfh_config_is_sym() currently rejects any hash field bitmap
> that contains bits outside the four paired L3/L4 fields.  This causes
> drivers that hash GTP flows on TEID to fail the kernel's preflight
> validation in ethtool_check_flow_types(), making it impossible for
> those drivers to support symmetric-xor transforms at all.
> 
> Strip RXH_GTP_TEID from the bitmap before the paired-field check so
> that drivers may honestly report TEID hashing without blocking the
> configuration of symmetric transforms.

I don't know much about GTP, but "the Internet" does not seem to agree
with your claim:

  The TEID uniquely identifies the GSN tunnel endpoints. The tunnels 
  for an uplink and a downlink are separate and use a different TEID.

https://docs.paloaltonetworks.com/service-providers/10-1/mobile-network-infrastructure-getting-started/gtp/mobile-network-protection-profile

So I don't think this will fly..