Re: [PATCH v2 iwl-net 2/2] idpf: fix issue with ethtool -n command display

[Simon Horman <horms@kernel.org>]

On Tue, Sep 30, 2025 at 04:23:52PM -0500, Sreedevi Joshi wrote:
> From: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>
> 
> When ethtool -n is executed on an interface to display the flow steering
> rules, "rxclass: Unknown flow type" error is generated.
> 
> The flow steering list maintained in the driver currently stores only the
> location and q_index but other fields of the ethtool_rx_flow_spec are not
> stored. This may be enough for the virtchnl command to delete the entry.
> However, when the ethtool -n command is used to query the flow steering
> rules, the ethtool_rx_flow_spec returned is not complete causing the
> error below.
> 
> Resolve this by storing the flow spec (fsp) when rules are added and
> returning the complete flow spec when rules are queried.
> 
> Also, change the return value from EINVAL to ENOENT when flow steering
> entry is not found during query by location or when deleting an entry.
> 
> Add logic to detect and reject duplicate filter entries at the same
> location and change logic to perform upfront validation of all error
> conditions before adding flow rules through virtchnl. This avoids the
> need for additional virtchnl delete messages when subsequent operations
> fail, which was missing in the original upstream code.
> 
> Example:
> Before the fix:
> ethtool -n eth1
> 2 RX rings available
> Total 2 rules
> 
> rxclass: Unknown flow type
> rxclass: Unknown flow type
> 
> After the fix:
> ethtool -n eth1
> 2 RX rings available
> Total 2 rules
> 
> Filter: 0
>         Rule Type: TCP over IPv4
>         Src IP addr: 10.0.0.1 mask: 0.0.0.0
>         Dest IP addr: 0.0.0.0 mask: 255.255.255.255
>         TOS: 0x0 mask: 0xff
>         Src port: 0 mask: 0xffff
>         Dest port: 0 mask: 0xffff
>         Action: Direct to queue 0
> 
> Filter: 1
>         Rule Type: UDP over IPv4
>         Src IP addr: 10.0.0.1 mask: 0.0.0.0
>         Dest IP addr: 0.0.0.0 mask: 255.255.255.255
>         TOS: 0x0 mask: 0xff
>         Src port: 0 mask: 0xffff
>         Dest port: 0 mask: 0xffff
>         Action: Direct to queue 0
> 
> Fixes: ada3e24b84a0 ("idpf: add flow steering support")
> Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>
> Co-developed-by: Sreedevi Joshi <sreedevi.joshi@intel.com>
> Signed-off-by: Sreedevi Joshi <sreedevi.joshi@intel.com>
> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>

Reviewed-by: Simon Horman <horms@kernel.org>