This series fixes VF bonding failures introduced by commit ad7c7b2172c3
("net: hold netdev instance lock during sysfs operations").When adding VFs to a bond immediately after setting trust mode, MAC address changes fail with -EAGAIN, preventing bonding setup. This affects both i40e (700-series) and ice (800-series) Intel NICs. The core issue is lock contention: iavf_set_mac() is now called with the netdev lock held and waits for MAC change completion while holding it. However, both the watchdog task that sends the request and the adminq_task that processes PF responses also need this lock, creating a deadlock where neither can run, causing timeouts. Additionally, setting VF trust triggers an unnecessary ~10 second VF reset in i40e driver that delays bonding setup, even though filter synchronization happens naturally during normal VF operation. For ice driver, the delay is not so big, but in the same way the operation is not necessary. This series: 1. Adds safety guard to prevent MAC changes during reset or early initialization (before VF is ready) 2. Eliminates unnecessary VF reset when setting trust in i40e (reset only if revoking trust and VF has advanced features configured). 3. Fixes lock contention by polling admin queue synchronously 4. Eliminates unnecessary VF reset when setting trust in ice, (reset only if revoking trust and VF has advanced features configured). The key fix (patch 3/4) implements a synchronous MAC change operation similar to the approach used for ndo_change_mtu deadlock fix: https://lore.kernel.org/intel-wired-lan/[email protected]/ Instead of scheduling work and waiting, it: - Sends the virtchnl message directly (not via watchdog) - Polls the admin queue hardware directly for responses - Processes all messages inline (including non-MAC messages) - Returns when complete or times out This allows the operation to complete synchronously while holding netdev_lock, without relying on watchdog or adminq_task. The function can sleep for up to 2.5 seconds polling hardware, but this is acceptable since netdev_lock is per-device and only serializes operations on the same interface. Testing shows VF bonding now works reliably in ~5 seconds vs 15+ seconds before (i40e), without timeouts or errors (i40e and ice). Tested on Intel 700-series (i40e) and 800-series (ice) dual-port NICs with iavf driver. Thanks to Jan Tluka <[email protected]> and Yuying Ma <[email protected]> for reporting the issues. Jose Ignacio Tornos Martinez (4): iavf: return EBUSY if reset in progress or not ready during MAC change i40e: skip unnecessary VF reset when setting trust iavf: send MAC change request synchronously ice: skip unnecessary VF reset when setting trust All patches tested successfully with bonding setup. --- v6: - Patch 1/4 (iavf EBUSY): No changes from v5 - Patch 2/4 (i40e trust): No code changes from v5. AI review comments covered design decisions and pre-existing issues, no bugs found in new code. - Patch 3/4 (iavf sync MAC): Address edge cases from AI review (Jakub Kicinski) - Allocate event buffer before sending to avoid state mismatch if allocation fails after message is sent to PF - Add loop to send all batches before polling (rare multi-batch scenario) - Conditional rollback: only rollback on send failure (ret != -EAGAIN), not on timeout where PF will eventually respond - Patch 4/4 (ice trust): Revert to original reset pattern based on AI review - AI review identified issues with v5's reset-before-cleanup approach (privilege bit not cleared, LLDP cleanup loop became dead code) - Restore proven cleanup → set trust → reset pattern from original code - Simpler implementation, no save/restore complexity - Maintains same goal: skip reset when VF has no advanced features v5: https://lore.kernel.org/all/[email protected]/ drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 38 ++++++++++++++++++++++++++++---------- drivers/net/ethernet/intel/iavf/iavf.h | 10 ++++++++-- drivers/net/ethernet/intel/iavf/iavf_main.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------- drivers/net/ethernet/intel/iavf/iavf_virtchnl.c | 103 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---------- drivers/net/ethernet/intel/ice/ice_sriov.c | 33 +++++++++++++++++++++++++++++---- 5 files changed, 220 insertions(+), 35 deletions(-) -- 2.43.0
