diff mbox series

[net] i40e: Fix handling changed priv flags

Message ID 20241113210705.1296408-1-anthony.l.nguyen@intel.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series [net] i40e: Fix handling changed priv flags | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 3 this patch: 3
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 3 this patch: 3
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 4 this patch: 4
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 8 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 44 this patch: 44
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-11-14--03-00 (tests: 782)

Commit Message

Tony Nguyen Nov. 13, 2024, 9:07 p.m. UTC
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.de/

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

Patch

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;