Re: [Intel-wired-lan] [PATCH iwl-net] ice: do not configure destination override for switchdev

[Simon Horman <horms@kernel.org>]

On Mon, Dec 09, 2024 at 03:08:53PM +0100, Larysa Zaremba wrote:
> After switchdev is enabled and disabled later, LLDP packets sending stops,
> despite working perfectly fine before and during switchdev state.
> To reproduce (creating/destroying VF is what triggers the reconfiguration):
> 
> devlink dev eswitch set pci/<address> mode switchdev
> echo '2' > /sys/class/net/<ifname>/device/sriov_numvfs
> echo '0' > /sys/class/net/<ifname>/device/sriov_numvfs
> 
> This happens because LLDP relies on the destination override functionality.
> It needs to 1) set a flag in the descriptor, 2) set the VSI permission to
> make it valid. The permissions are set when the PF VSI is first configured,
> but switchdev then enables it for the uplink VSI (which is always the PF)
> once more when configured and disables when deconfigured, which leads to
> software-generated LLDP packets being blocked.
> 
> Do not modify the destination override permissions when configuring
> switchdev, as the enabled state is the default configuration that is never
> modified.
> 
> Fixes: 1a1c40df2e80 ("ice: set and release switchdev environment")
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>

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