[PATCH iwl-next] ice: fix system hang on `ethtool -L`

[Alexander Lobakin <aleksander.lobakin@intel.com>]

ice_set_channels() calls ice_vsi_rebuild() under the netdev lock
taken, but ice_vsi_rebuild() calls netif_napi_{add,del}() which
take the same lock.
Add ice_vsi_rebuild_locked() which uses the _locked counterparts
of these functions and use it in ice_set_channels().

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
---
Hey Tony, please amend to the patch I replied to.
---
 drivers/net/ethernet/intel/ice/ice_base.h |  2 +
 drivers/net/ethernet/intel/ice/ice_lib.h  |  1 +
 drivers/net/ethernet/intel/ice/ice_base.c | 63 ++++++++++++---
 drivers/net/ethernet/intel/ice/ice_lib.c  | 94 ++++++++++++++++++++---
 drivers/net/ethernet/intel/ice/ice_main.c |  5 +-
 5 files changed, 143 insertions(+), 22 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_base.h b/drivers/net/ethernet/intel/ice/ice_base.h
index d28294247599..99b2c7232829 100644
--- a/drivers/net/ethernet/intel/ice/ice_base.h
+++ b/drivers/net/ethernet/intel/ice/ice_base.h
@@ -12,8 +12,10 @@ int __ice_vsi_get_qs(struct ice_qs_cfg *qs_cfg);
 int
 ice_vsi_ctrl_one_rx_ring(struct ice_vsi *vsi, bool ena, u16 rxq_idx, bool wait);
 int ice_vsi_wait_one_rx_ring(struct ice_vsi *vsi, bool ena, u16 rxq_idx);
+int ice_vsi_alloc_q_vectors_locked(struct ice_vsi *vsi);
 int ice_vsi_alloc_q_vectors(struct ice_vsi *vsi);
 void ice_vsi_map_rings_to_vectors(struct ice_vsi *vsi);
+void ice_vsi_free_q_vectors_locked(struct ice_vsi *vsi);
 void ice_vsi_free_q_vectors(struct ice_vsi *vsi);
 int ice_vsi_cfg_single_txq(struct ice_vsi *vsi, struct ice_tx_ring **tx_rings,
 			   u16 q_idx);
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.h b/drivers/net/ethernet/intel/ice/ice_lib.h
index 347b63e497e7..e55b72db72c4 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.h
+++ b/drivers/net/ethernet/intel/ice/ice_lib.h
@@ -68,6 +68,7 @@ int ice_ena_vsi(struct ice_vsi *vsi, bool locked);
 void ice_vsi_decfg(struct ice_vsi *vsi);
 void ice_dis_vsi(struct ice_vsi *vsi, bool locked);
 
+int ice_vsi_rebuild_locked(struct ice_vsi *vsi, u32 vsi_flags);
 int ice_vsi_rebuild(struct ice_vsi *vsi, u32 vsi_flags);
 int ice_vsi_cfg(struct ice_vsi *vsi);
 struct ice_vsi *ice_vsi_alloc(struct ice_pf *pf);
diff --git a/drivers/net/ethernet/intel/ice/ice_base.c b/drivers/net/ethernet/intel/ice/ice_base.c
index 7097324c38f3..65e19815bec5 100644
--- a/drivers/net/ethernet/intel/ice/ice_base.c
+++ b/drivers/net/ethernet/intel/ice/ice_base.c
@@ -153,8 +153,8 @@ static int ice_vsi_alloc_q_vector(struct ice_vsi *vsi, u16 v_idx)
 	 * handler here (i.e. resume, reset/rebuild, etc.)
 	 */
 	if (vsi->netdev)
-		netif_napi_add_config(vsi->netdev, &q_vector->napi,
-				      ice_napi_poll, v_idx);
+		netif_napi_add_config_locked(vsi->netdev, &q_vector->napi,
+					     ice_napi_poll, v_idx);
 
 out:
 	/* tie q_vector and VSI together */
@@ -196,7 +196,7 @@ static void ice_free_q_vector(struct ice_vsi *vsi, int v_idx)
 
 	/* only VSI with an associated netdev is set up with NAPI */
 	if (vsi->netdev)
-		netif_napi_del(&q_vector->napi);
+		netif_napi_del_locked(&q_vector->napi);
 
 	/* release MSIX interrupt if q_vector had interrupt allocated */
 	if (q_vector->irq.index < 0)
@@ -896,13 +896,15 @@ int ice_vsi_wait_one_rx_ring(struct ice_vsi *vsi, bool ena, u16 rxq_idx)
 }
 
 /**
- * ice_vsi_alloc_q_vectors - Allocate memory for interrupt vectors
+ * ice_vsi_alloc_q_vectors_locked - Allocate memory for interrupt vectors
  * @vsi: the VSI being configured
  *
- * We allocate one q_vector per queue interrupt. If allocation fails we
- * return -ENOMEM.
+ * Should be called only under the netdev lock.
+ * We allocate one q_vector per queue interrupt.
+ *
+ * Return: 0 on success, -ENOMEM if allocation fails.
  */
-int ice_vsi_alloc_q_vectors(struct ice_vsi *vsi)
+int ice_vsi_alloc_q_vectors_locked(struct ice_vsi *vsi)
 {
 	struct device *dev = ice_pf_to_dev(vsi->back);
 	u16 v_idx;
@@ -929,6 +931,30 @@ int ice_vsi_alloc_q_vectors(struct ice_vsi *vsi)
 	return v_idx ? 0 : err;
 }
 
+/**
+ * ice_vsi_alloc_q_vectors - Allocate memory for interrupt vectors
+ * @vsi: the VSI being configured
+ *
+ * We allocate one q_vector per queue interrupt.
+ *
+ * Return: 0 on success, -ENOMEM if allocation fails.
+ */
+int ice_vsi_alloc_q_vectors(struct ice_vsi *vsi)
+{
+	struct net_device *dev = vsi->netdev;
+	int ret;
+
+	if (dev)
+		netdev_lock(dev);
+
+	ret = ice_vsi_alloc_q_vectors_locked(vsi);
+
+	if (dev)
+		netdev_unlock(dev);
+
+	return ret;
+}
+
 /**
  * ice_vsi_map_rings_to_vectors - Map VSI rings to interrupt vectors
  * @vsi: the VSI being configured
@@ -992,10 +1018,12 @@ void ice_vsi_map_rings_to_vectors(struct ice_vsi *vsi)
 }
 
 /**
- * ice_vsi_free_q_vectors - Free memory allocated for interrupt vectors
+ * ice_vsi_free_q_vectors_locked - Free memory allocated for interrupt vectors
  * @vsi: the VSI having memory freed
+ *
+ * Should be called only under the netdev lock.
  */
-void ice_vsi_free_q_vectors(struct ice_vsi *vsi)
+void ice_vsi_free_q_vectors_locked(struct ice_vsi *vsi)
 {
 	int v_idx;
 
@@ -1005,6 +1033,23 @@ void ice_vsi_free_q_vectors(struct ice_vsi *vsi)
 	vsi->num_q_vectors = 0;
 }
 
+/**
+ * ice_vsi_free_q_vectors - Free memory allocated for interrupt vectors
+ * @vsi: the VSI having memory freed
+ */
+void ice_vsi_free_q_vectors(struct ice_vsi *vsi)
+{
+	struct net_device *dev = vsi->netdev;
+
+	if (dev)
+		netdev_lock(dev);
+
+	ice_vsi_free_q_vectors_locked(vsi);
+
+	if (dev)
+		netdev_unlock(dev);
+}
+
 /**
  * ice_cfg_tstamp - Configure Tx time stamp queue
  * @tx_ring: Tx ring to be configured with timestamping
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
index 041278caf8e3..f647e583d198 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -2308,10 +2308,14 @@ static int ice_vsi_cfg_tc_lan(struct ice_pf *pf, struct ice_vsi *vsi)
 }
 
 /**
- * ice_vsi_cfg_def - configure default VSI based on the type
+ * ice_vsi_cfg_def_locked - configure default VSI based on the type
  * @vsi: pointer to VSI
+ *
+ * Should be called only with the netdev lock taken.
+ *
+ * Return: 0 on success, -errno on failure.
  */
-static int ice_vsi_cfg_def(struct ice_vsi *vsi)
+static int ice_vsi_cfg_def_locked(struct ice_vsi *vsi)
 {
 	struct device *dev = ice_pf_to_dev(vsi->back);
 	struct ice_pf *pf = vsi->back;
@@ -2354,7 +2358,7 @@ static int ice_vsi_cfg_def(struct ice_vsi *vsi)
 	case ICE_VSI_CTRL:
 	case ICE_VSI_SF:
 	case ICE_VSI_PF:
-		ret = ice_vsi_alloc_q_vectors(vsi);
+		ret = ice_vsi_alloc_q_vectors_locked(vsi);
 		if (ret)
 			goto unroll_vsi_init;
 
@@ -2404,7 +2408,7 @@ static int ice_vsi_cfg_def(struct ice_vsi *vsi)
 		 * creates a VSI and corresponding structures for bookkeeping
 		 * purpose
 		 */
-		ret = ice_vsi_alloc_q_vectors(vsi);
+		ret = ice_vsi_alloc_q_vectors_locked(vsi);
 		if (ret)
 			goto unroll_vsi_init;
 
@@ -2460,6 +2464,28 @@ static int ice_vsi_cfg_def(struct ice_vsi *vsi)
 	return ret;
 }
 
+/**
+ * ice_vsi_cfg_def - configure default VSI based on the type
+ * @vsi: pointer to VSI
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+static int ice_vsi_cfg_def(struct ice_vsi *vsi)
+{
+	struct net_device *dev = vsi->netdev;
+	int ret;
+
+	if (dev)
+		netdev_lock(dev);
+
+	ret = ice_vsi_cfg_def_locked(vsi);
+
+	if (dev)
+		netdev_unlock(dev);
+
+	return ret;
+}
+
 /**
  * ice_vsi_cfg - configure a previously allocated VSI
  * @vsi: pointer to VSI
@@ -2494,10 +2520,12 @@ int ice_vsi_cfg(struct ice_vsi *vsi)
 }
 
 /**
- * ice_vsi_decfg - remove all VSI configuration
+ * ice_vsi_decfg_locked - remove all VSI configuration
  * @vsi: pointer to VSI
+ *
+ * Should be called only under the netdev lock.
  */
-void ice_vsi_decfg(struct ice_vsi *vsi)
+static void ice_vsi_decfg_locked(struct ice_vsi *vsi)
 {
 	struct ice_pf *pf = vsi->back;
 	int err;
@@ -2515,7 +2543,7 @@ void ice_vsi_decfg(struct ice_vsi *vsi)
 		ice_destroy_xdp_rings(vsi, ICE_XDP_CFG_PART);
 
 	ice_vsi_clear_rings(vsi);
-	ice_vsi_free_q_vectors(vsi);
+	ice_vsi_free_q_vectors_locked(vsi);
 	ice_vsi_put_qs(vsi);
 	ice_vsi_free_arrays(vsi);
 
@@ -2530,6 +2558,23 @@ void ice_vsi_decfg(struct ice_vsi *vsi)
 		vsi->agg_node->num_vsis--;
 }
 
+/**
+ * ice_vsi_decfg - remove all VSI configuration
+ * @vsi: pointer to VSI
+ */
+void ice_vsi_decfg(struct ice_vsi *vsi)
+{
+	struct net_device *dev = vsi->netdev;
+
+	if (dev)
+		netdev_lock(dev);
+
+	ice_vsi_decfg_locked(vsi);
+
+	if (dev)
+		netdev_unlock(dev);
+}
+
 /**
  * ice_vsi_setup - Set up a VSI by a given type
  * @pf: board private structure
@@ -3107,16 +3152,17 @@ ice_vsi_realloc_stat_arrays(struct ice_vsi *vsi)
 }
 
 /**
- * ice_vsi_rebuild - Rebuild VSI after reset
+ * ice_vsi_rebuild_locked - Rebuild VSI after reset
  * @vsi: VSI to be rebuild
  * @vsi_flags: flags used for VSI rebuild flow
  *
  * Set vsi_flags to ICE_VSI_FLAG_INIT to initialize a new VSI, or
  * ICE_VSI_FLAG_NO_INIT to rebuild an existing VSI in hardware.
+ * Should be called only under the netdev lock.
  *
  * Returns 0 on success and negative value on failure
  */
-int ice_vsi_rebuild(struct ice_vsi *vsi, u32 vsi_flags)
+int ice_vsi_rebuild_locked(struct ice_vsi *vsi, u32 vsi_flags)
 {
 	struct ice_coalesce_stored *coalesce;
 	int prev_num_q_vectors;
@@ -3137,8 +3183,8 @@ int ice_vsi_rebuild(struct ice_vsi *vsi, u32 vsi_flags)
 	if (ret)
 		goto unlock;
 
-	ice_vsi_decfg(vsi);
-	ret = ice_vsi_cfg_def(vsi);
+	ice_vsi_decfg_locked(vsi);
+	ret = ice_vsi_cfg_def_locked(vsi);
 	if (ret)
 		goto unlock;
 
@@ -3175,6 +3221,32 @@ int ice_vsi_rebuild(struct ice_vsi *vsi, u32 vsi_flags)
 	return ret;
 }
 
+/**
+ * ice_vsi_rebuild - Rebuild VSI after reset
+ * @vsi: VSI to be rebuild
+ * @vsi_flags: flags used for VSI rebuild flow
+ *
+ * Set vsi_flags to ICE_VSI_FLAG_INIT to initialize a new VSI, or
+ * ICE_VSI_FLAG_NO_INIT to rebuild an existing VSI in hardware.
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int ice_vsi_rebuild(struct ice_vsi *vsi, u32 vsi_flags)
+{
+	struct net_device *dev = vsi->netdev;
+	int ret;
+
+	if (dev)
+		netdev_lock(dev);
+
+	ret = ice_vsi_rebuild_locked(vsi, vsi_flags);
+
+	if (dev)
+		netdev_unlock(dev);
+
+	return ret;
+}
+
 /**
  * ice_is_reset_in_progress - check for a reset in progress
  * @state: PF state field
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index 7a1c6859d708..b9d726797919 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -4130,6 +4130,7 @@ bool ice_is_wol_supported(struct ice_hw *hw)
  * @locked: is adev device_lock held
  *
  * Only change the number of queues if new_tx, or new_rx is non-0.
+ * Note that it should be called only with the netdev lock taken.
  *
  * Returns 0 on success.
  */
@@ -4155,7 +4156,7 @@ int ice_vsi_recfg_qs(struct ice_vsi *vsi, int new_rx, int new_tx, bool locked)
 
 	/* set for the next time the netdev is started */
 	if (!netif_running(vsi->netdev)) {
-		err = ice_vsi_rebuild(vsi, ICE_VSI_FLAG_NO_INIT);
+		err = ice_vsi_rebuild_locked(vsi, ICE_VSI_FLAG_NO_INIT);
 		if (err)
 			goto rebuild_err;
 		dev_dbg(ice_pf_to_dev(pf), "Link is down, queue count change happens when link is brought up\n");
@@ -4163,7 +4164,7 @@ int ice_vsi_recfg_qs(struct ice_vsi *vsi, int new_rx, int new_tx, bool locked)
 	}
 
 	ice_vsi_close(vsi);
-	err = ice_vsi_rebuild(vsi, ICE_VSI_FLAG_NO_INIT);
+	err = ice_vsi_rebuild_locked(vsi, ICE_VSI_FLAG_NO_INIT);
 	if (err)
 		goto rebuild_err;
 
-- 
2.52.0