From: Peter Große pegro@friiks.de

After assembling the new private flags on a PF, the operation to determine the changed flags uses the wrong bitmaps. Instead of xor-ing orig_flags with new_flags, it uses the still unchanged pf->flags, thus changed_flags is always 0.

Fix it by using the correct bitmaps.

The issue was discovered while debugging why disabling source pruning stopped working with release 6.7. Although the new flags will be copied to pf->flags later on in that function, disabling source pruning requires a reset of the PF, which was skipped due to this bug.

Disabling source pruning: $ sudo ethtool --set-priv-flags eno1 disable-source-pruning on $ sudo ethtool --show-priv-flags eno1 Private flags for eno1: MFP : off total-port-shutdown : off LinkPolling : off flow-director-atr : on veb-stats : off hw-atr-eviction : off link-down-on-close : off legacy-rx : off disable-source-pruning: on disable-fw-lldp : off rs-fec : off base-r-fec : off vf-vlan-pruning : off

Regarding reproducing:

I observed the issue with a rather complicated lab setup, where * two VLAN interfaces are created on eno1 * each with a different MAC address assigned * each moved into a separate namespace * both VLANs are bridged externally, so they form a single layer 2 network

The external bridge is done via a channel emulator adding packet loss and delay and the application in the namespaces tries to send/receive traffic and measure the performance. Sender and receiver are separated by namespaces, yet the network card "sees its own traffic" send back to it. To make that work, source pruning has to be disabled.

Cc: stable@vger.kernel.org Fixes: 70756d0a4727 ("i40e: Use DECLARE_BITMAP for flags and hw_features fields in i40e_pf") Signed-off-by: Peter Große pegro@friiks.de Reviewed-by: Paul Menzel pmenzel@molgen.mpg.de Reviewed-by: Przemek Kitszel przemyslaw.kitszel@intel.com Tested-by: Pucha Himasekhar Reddy himasekharx.reddy.pucha@intel.com (A Contingent worker at Intel) Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com --- iwl: https://lore.kernel.org/intel-wired-lan/20241030160643.9950-1-pegro@friiks.d...

drivers/net/ethernet/intel/i40e/i40e_ethtool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c index f2506511bbff..bce5b76f1e7a 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c +++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c @@ -5299,7 +5299,7 @@ static int i40e_set_priv_flags(struct net_device *dev, u32 flags) }

flags_complete: - bitmap_xor(changed_flags, pf->flags, orig_flags, I40E_PF_FLAGS_NBITS); + bitmap_xor(changed_flags, new_flags, orig_flags, I40E_PF_FLAGS_NBITS);

if (test_bit(I40E_FLAG_FW_LLDP_DIS, changed_flags)) reset_needed = I40E_PF_RESET_AND_REBUILD_FLAG;