[PATCH net v2 0/4] Fix i40e/ice/iavf VF bonding after netdev lock changes

[PATCH net v2 0/4] Fix i40e/ice/iavf VF bonding after netdev lock changes

[Jose Ignacio Tornos Martinez]

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
3. Fixes lock contention by polling admin queue synchronously
4. Eliminates unnecessary VF reset when setting trust in ice

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/20260211191855.1532226-1-poros@redhat.com/ 
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. A new generic
iavf_poll_virtchnl_response() function is introduced that can be reused
for future synchronous virtchnl operations.

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 <jtluka@redhat.com> and Yuying Ma <yuma@redhat.com> for
reporting the issues.

Jose Ignacio Tornos Martinez (4):
  iavf: return EBUSY if reset in progress 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

---
v2:
  - Patch 1: Add state check to prevent MAC changes during early
    initialization (before __IAVF_DOWN state)
  - Patch 3: Use synchronous polling approach instead of dropping lock,
    following the pattern from ndo_change_mtu deadlock fix
  - Introduce generic iavf_poll_virtchnl_response() for code reuse
  - Add patch 4/4 to fix the same trust reset issue in ice driver
  - Add testing confirmation for both i40e and ice hardware
  - No changes to patch 2 from v1
v1: https://lore.kernel.org/netdev/20260406112057.906685-1-jtornosm@redhat.com/

 drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 17 ++-
 drivers/net/ethernet/intel/iavf/iavf.h             |  2 +-
 drivers/net/ethernet/intel/iavf/iavf_main.c        | 98 +++++++++++++++++-
 drivers/net/ethernet/intel/iavf/iavf_virtchnl.c    | 15 +--
 drivers/net/ethernet/intel/ice/ice_sriov.c         | 15 ++-
 5 files changed, 123 insertions(+), 24 deletions(-)

--
2.43.0

[PATCH net v2 1/4] iavf: return EBUSY if reset in progress or not ready during MAC change

[Jose Ignacio Tornos Martinez]

When a MAC address change is requested while the VF is resetting or still
initializing, return -EBUSY immediately instead of attempting the
operation.

Additionally, during early initialization states (before __IAVF_DOWN),
the PF may be slow to respond to MAC change requests, causing long
delays. Only allow MAC changes once the VF reaches __IAVF_DOWN state or
later, when the watchdog is running and the VF is ready for operations.

After commit ad7c7b2172c3 ("net: hold netdev instance lock
during sysfs operations"), MAC changes are called with the netdev lock
held, so we should not wait with the lock held during reset or
initialization. This allows the caller to retry or handle the busy state
appropriately without blocking other operations.

Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
---
v2: Add state check to prevent MAC changes during early initialization
    states (before __IAVF_DOWN). In v1 this patch only checked for reset
    in progress.
v1: https://lore.kernel.org/netdev/20260406112057.906685-2-jtornosm@redhat.com/

 drivers/net/ethernet/intel/iavf/iavf_main.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index dad001abc908..67aa14350b1b 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -1060,6 +1060,9 @@ static int iavf_set_mac(struct net_device *netdev, void *p)
 	struct sockaddr *addr = p;
 	int ret;
 
+	if (iavf_is_reset_in_progress(adapter) || adapter->state < __IAVF_DOWN)
+		return -EBUSY;
+
 	if (!is_valid_ether_addr(addr->sa_data))
 		return -EADDRNOTAVAIL;
 
-- 
2.53.0

[PATCH net v2 2/4] i40e: skip unnecessary VF reset when setting trust

[Jose Ignacio Tornos Martinez]

When VF trust is changed, i40e_ndo_set_vf_trust() always calls
i40e_vc_reset_vf() to sync MAC/VLAN filters. However, this reset is
only necessary when trust is removed from a VF that has ADQ (advanced
queue) filters, which need to be deleted

In all other cases, the reset causes a ~10 second delay during which:
- VF must reinitialize completely
- Any in-progress operations (like bonding enslave) fail with timeouts
- VF is unavailable

The MAC/VLAN filter sync will happen naturally through the normal VF
operations and doesn't require a forced reset.

Fix by only resetting when actually needed: when removing trust from a
VF that has ADQ cloud filters. For all other trust changes, just update
the trust flag and let normal operation continue.

Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
---
 drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
index a26c3d47ec15..fea267af7afe 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
@@ -4987,16 +4987,21 @@ int i40e_ndo_set_vf_trust(struct net_device *netdev, int vf_id, bool setting)
 	set_bit(__I40E_MACVLAN_SYNC_PENDING, pf->state);
 	pf->vsi[vf->lan_vsi_idx]->flags |= I40E_VSI_FLAG_FILTER_CHANGED;
 
-	i40e_vc_reset_vf(vf, true);
 	dev_info(&pf->pdev->dev, "VF %u is now %strusted\n",
 		 vf_id, setting ? "" : "un");
 
+	/* Only reset VF if we're removing trust and it has ADQ cloud filters.
+	 * Cloud filters can only be added when trusted, so they must be
+	 * removed when trust is revoked. Other trust changes don't require
+	 * reset - MAC/VLAN filter sync happens through normal operation.
+	 */
 	if (vf->adq_enabled) {
 		if (!vf->trusted) {
 			dev_info(&pf->pdev->dev,
 				 "VF %u no longer Trusted, deleting all cloud filters\n",
 				 vf_id);
 			i40e_del_all_cloud_filters(vf);
+			i40e_vc_reset_vf(vf, true);
 		}
 	}
 
-- 
2.53.0

[PATCH net v2 3/4] iavf: send MAC change request synchronously

[Jose Ignacio Tornos Martinez]

After commit ad7c7b2172c3 ("net: hold netdev instance lock during sysfs
operations"), iavf_set_mac() is called with the netdev instance lock
already held.

The function queues a MAC address change request via
iavf_replace_primary_mac() and then waits for completion. However, in
the current flow, the actual virtchnl message is sent by the watchdog
task, which also needs to acquire the netdev lock to run. Additionally,
the adminq_task which processes virtchnl responses also needs the netdev
lock.

This creates a deadlock scenario:
1. iavf_set_mac() holds netdev lock and waits for MAC change
2. Watchdog needs netdev lock to send the request -> blocked
3. Even if request is sent, adminq_task needs netdev lock to process
   PF response -> blocked
4. MAC change times out after 2.5 seconds
5. iavf_set_mac() returns -EAGAIN

This particularly affects VFs during bonding setup when multiple VFs are
enslaved in quick succession.

Fix by implementing a synchronous MAC change operation similar to the
approach used in commit fdadbf6e84c4 ("iavf: fix incorrect reset handling
in callbacks").

The solution:
1. Send the virtchnl ADD_ETH_ADDR message directly (not via watchdog)
2. Poll the admin queue hardware directly for responses
3. Process all received messages (including non-MAC messages)
4. Return when MAC change completes or times out

A new generic function iavf_poll_virtchnl_response() is introduced that
can be reused for any future synchronous virtchnl operations. It takes a
callback to check completion, allowing flexible condition checking.

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.

To support this, change iavf_add_ether_addrs() to return an error code
instead of void, allowing callers to detect failures.

Fixes: ad7c7b2172c3 ("net: hold netdev instance lock during sysfs operations")
cc: stable@vger.kernel.org
Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
---
v2: Complete rewrite using synchronous polling approach instead of dropping
    the netdev lock. New approach:
    - Polls admin queue hardware directly (similar to iavf_reset_step)
    - Processes all virtchnl messages inline while holding netdev_lock
    - Introduced generic iavf_poll_virtchnl_response() for code reuse
    - No lock dropping, following accepted pattern from ndo_change_mtu fix
v1: https://lore.kernel.org/netdev/20260406112057.906685-4-jtornosm@redhat.com/

 drivers/net/ethernet/intel/iavf/iavf.h        |   2 +-
 drivers/net/ethernet/intel/iavf/iavf_main.c   | 118 +++++++++++++++---
 .../net/ethernet/intel/iavf/iavf_virtchnl.c   |  11 +-
 3 files changed, 110 insertions(+), 21 deletions(-)

diff --git a/drivers/net/ethernet/intel/iavf/iavf.h b/drivers/net/ethernet/intel/iavf/iavf.h
index e9fb0a0919e3..5bc23519fe9c 100644
--- a/drivers/net/ethernet/intel/iavf/iavf.h
+++ b/drivers/net/ethernet/intel/iavf/iavf.h
@@ -589,7 +589,7 @@ void iavf_configure_queues(struct iavf_adapter *adapter);
 void iavf_enable_queues(struct iavf_adapter *adapter);
 void iavf_disable_queues(struct iavf_adapter *adapter);
 void iavf_map_queues(struct iavf_adapter *adapter);
-void iavf_add_ether_addrs(struct iavf_adapter *adapter);
+int iavf_add_ether_addrs(struct iavf_adapter *adapter);
 void iavf_del_ether_addrs(struct iavf_adapter *adapter);
 void iavf_add_vlans(struct iavf_adapter *adapter);
 void iavf_del_vlans(struct iavf_adapter *adapter);
diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 67aa14350b1b..2ef30b1ef35c 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -1047,6 +1047,105 @@ static bool iavf_is_mac_set_handled(struct net_device *netdev,
 	return ret;
 }
 
+/**
+ * iavf_poll_virtchnl_response - Poll admin queue for virtchnl response
+ * @adapter: board private structure
+ * @condition: callback to check if desired response received
+ * @cond_data: context data passed to condition callback
+ * @timeout_ms: maximum time to wait in milliseconds
+ *
+ * Polls admin queue and processes all messages until condition returns true
+ * or timeout expires. Caller must hold netdev_lock. This can sleep for up to
+ * timeout_ms while polling hardware.
+ *
+ * Returns 0 on success (condition met), -EAGAIN on timeout or error
+ */
+static int iavf_poll_virtchnl_response(struct iavf_adapter *adapter,
+				       bool (*condition)(struct iavf_adapter *, void *),
+				       void *cond_data,
+				       unsigned int timeout_ms)
+{
+	struct iavf_hw *hw = &adapter->hw;
+	struct iavf_arq_event_info event;
+	enum virtchnl_ops v_op;
+	enum iavf_status v_ret;
+	unsigned long timeout;
+	int ret;
+
+	netdev_assert_locked(adapter->netdev);
+
+	event.buf_len = IAVF_MAX_AQ_BUF_SIZE;
+	event.msg_buf = kzalloc(event.buf_len, GFP_KERNEL);
+	if (!event.msg_buf)
+		return -ENOMEM;
+
+	timeout = jiffies + msecs_to_jiffies(timeout_ms);
+	while (time_before(jiffies, timeout)) {
+		if (condition(adapter, cond_data)) {
+			ret = 0;
+			goto out;
+		}
+
+		ret = iavf_clean_arq_element(hw, &event, NULL);
+		if (!ret) {
+			v_op = (enum virtchnl_ops)le32_to_cpu(event.desc.cookie_high);
+			v_ret = (enum iavf_status)le32_to_cpu(event.desc.cookie_low);
+
+			iavf_virtchnl_completion(adapter, v_op, v_ret,
+						 event.msg_buf, event.msg_len);
+
+			memset(event.msg_buf, 0, IAVF_MAX_AQ_BUF_SIZE);
+		}
+
+		usleep_range(1000, 2000);
+	}
+
+	ret = -EAGAIN;
+out:
+	kfree(event.msg_buf);
+	return ret;
+}
+
+/**
+ * iavf_mac_change_done - Check if MAC change completed
+ * @adapter: board private structure
+ * @data: MAC address being checked (as void *)
+ *
+ * Callback for iavf_poll_virtchnl_response() to check if MAC change completed.
+ *
+ * Returns true if MAC change completed, false otherwise
+ */
+static bool iavf_mac_change_done(struct iavf_adapter *adapter, void *data)
+{
+	const u8 *addr = data;
+
+	return iavf_is_mac_set_handled(adapter->netdev, addr);
+}
+
+/**
+ * iavf_set_mac_sync - Synchronously change MAC address
+ * @adapter: board private structure
+ * @addr: MAC address to set
+ *
+ * Sends MAC change request to PF and polls admin queue for response.
+ * Caller must hold netdev_lock. This can sleep for up to 2.5 seconds.
+ *
+ * Returns 0 on success or error
+ */
+static int iavf_set_mac_sync(struct iavf_adapter *adapter, const u8 *addr)
+{
+	int ret;
+
+	netdev_assert_locked(adapter->netdev);
+
+	ret = iavf_add_ether_addrs(adapter);
+	if (ret)
+		return ret;
+
+	return iavf_poll_virtchnl_response(adapter, iavf_mac_change_done,
+					   (void *)addr, 2500);
+}
+
 /**
  * iavf_set_mac - NDO callback to set port MAC address
  * @netdev: network interface device structure
@@ -1067,25 +1166,12 @@ static int iavf_set_mac(struct net_device *netdev, void *p)
 		return -EADDRNOTAVAIL;
 
 	ret = iavf_replace_primary_mac(adapter, addr->sa_data);
-
 	if (ret)
 		return ret;
 
-	ret = wait_event_interruptible_timeout(adapter->vc_waitqueue,
-					       iavf_is_mac_set_handled(netdev, addr->sa_data),
-					       msecs_to_jiffies(2500));
-
-	/* If ret < 0 then it means wait was interrupted.
-	 * If ret == 0 then it means we got a timeout.
-	 * else it means we got response for set MAC from PF,
-	 * check if netdev MAC was updated to requested MAC,
-	 * if yes then set MAC succeeded otherwise it failed return -EACCES
-	 */
-	if (ret < 0)
-		return ret;
-
-	if (!ret)
-		return -EAGAIN;
+	ret = iavf_set_mac_sync(adapter, addr->sa_data);
+	if (ret)
+		return ret;
 
 	if (!ether_addr_equal(netdev->dev_addr, addr->sa_data))
 		return -EACCES;
diff --git a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c
index a52c100dcbc5..fdddf4b033ca 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c
@@ -555,8 +555,10 @@ iavf_set_mac_addr_type(struct virtchnl_ether_addr *virtchnl_ether_addr,
  * @adapter: adapter structure
  *
  * Request that the PF add one or more addresses to our filters.
+ *
+ * Returns 0 on success or error
  **/
-void iavf_add_ether_addrs(struct iavf_adapter *adapter)
+int iavf_add_ether_addrs(struct iavf_adapter *adapter)
 {
 	struct virtchnl_ether_addr_list *veal;
 	struct iavf_mac_filter *f;
@@ -568,7 +570,7 @@ void iavf_add_ether_addrs(struct iavf_adapter *adapter)
 		/* bail because we already have a command pending */
 		dev_err(&adapter->pdev->dev, "Cannot add filters, command %d pending\n",
 			adapter->current_op);
-		return;
+		return -EBUSY;
 	}
 
 	spin_lock_bh(&adapter->mac_vlan_list_lock);
@@ -580,7 +582,7 @@ void iavf_add_ether_addrs(struct iavf_adapter *adapter)
 	if (!count) {
 		adapter->aq_required &= ~IAVF_FLAG_AQ_ADD_MAC_FILTER;
 		spin_unlock_bh(&adapter->mac_vlan_list_lock);
-		return;
+		return 0;
 	}
 	adapter->current_op = VIRTCHNL_OP_ADD_ETH_ADDR;
 
@@ -595,7 +597,7 @@ void iavf_add_ether_addrs(struct iavf_adapter *adapter)
 	veal = kzalloc(len, GFP_ATOMIC);
 	if (!veal) {
 		spin_unlock_bh(&adapter->mac_vlan_list_lock);
-		return;
+		return -ENOMEM;
 	}
 
 	veal->vsi_id = adapter->vsi_res->vsi_id;
@@ -617,6 +619,7 @@ void iavf_add_ether_addrs(struct iavf_adapter *adapter)
 
 	iavf_send_pf_msg(adapter, VIRTCHNL_OP_ADD_ETH_ADDR, (u8 *)veal, len);
 	kfree(veal);
+	return 0;
 }
 
 /**
-- 
2.53.0

[PATCH net v2 4/4] ice: skip unnecessary VF reset when setting trust

[Jose Ignacio Tornos Martinez]

Similar to the i40e fix, ice_set_vf_trust() unconditionally calls
ice_reset_vf() when the trust setting changes.

The ice driver already has logic to clean up MAC LLDP filters when
removing trust, which is the only operation that requires filter
synchronization. After this cleanup, the VF reset is only necessary if
there were actually filters to remove.

For all other trust state changes (setting trust, or removing trust
when no filters exist), the reset is unnecessary as filter
synchronization happens naturally through normal VF operations.

Fix by only triggering the VF reset when removing trust AND filters
were actually cleaned up (num_mac_lldp was non-zero).

This saves some time and eliminates unnecessary service disruption when
changing VF trust settings if not necessary.

Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
---
 drivers/net/ethernet/intel/ice/ice_sriov.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_sriov.c b/drivers/net/ethernet/intel/ice/ice_sriov.c
index 7e00e091756d..23f692b1e86c 100644
--- a/drivers/net/ethernet/intel/ice/ice_sriov.c
+++ b/drivers/net/ethernet/intel/ice/ice_sriov.c
@@ -1399,14 +1399,19 @@ int ice_set_vf_trust(struct net_device *netdev, int vf_id, bool trusted)
 
 	mutex_lock(&vf->cfg_lock);
 
-	while (!trusted && vf->num_mac_lldp)
-		ice_vf_update_mac_lldp_num(vf, ice_get_vf_vsi(vf), false);
-
 	vf->trusted = trusted;
-	ice_reset_vf(vf, ICE_VF_RESET_NOTIFY);
 	dev_info(ice_pf_to_dev(pf), "VF %u is now %strusted\n",
 		 vf_id, trusted ? "" : "un");
 
+	/* Only reset VF if removing trust and there are MAC LLDP filters
+	 * to clean up. Reset is needed to ensure filter removal completes.
+	 */
+	if (!trusted && vf->num_mac_lldp) {
+		while (vf->num_mac_lldp)
+			ice_vf_update_mac_lldp_num(vf, ice_get_vf_vsi(vf), false);
+		ice_reset_vf(vf, ICE_VF_RESET_NOTIFY);
+	}
+
 	mutex_unlock(&vf->cfg_lock);
 
 out_put_vf:
-- 
2.53.0