ice: convert VF storage to hash table with krefs and RCU

The ice driver stores VF structures in a simple array which is allocated
once at the time of VF creation. The VF structures are then accessed
from the array by their VF ID. The ID must be between 0 and the number
of allocated VFs.

Multiple threads can access this table:

 * .ndo operations such as .ndo_get_vf_cfg or .ndo_set_vf_trust
 * interrupts, such as due to messages from the VF using the virtchnl
   communication
 * processing such as device reset
 * commands to add or remove VFs

The current implementation does not keep track of when all threads are
done operating on a VF and can potentially result in use-after-free
issues caused by one thread accessing a VF structure after it has been
released when removing VFs. Some of these are prevented with various
state flags and checks.

In addition, this structure is quite static and does not support a
planned future where virtualization can be more dynamic. As we begin to
look at supporting Scalable IOV with the ice driver (as opposed to just
supporting Single Root IOV), this structure is not sufficient.

In the future, VFs will be able to be added and removed individually and
dynamically.

To allow for this, and to better protect against a whole class of
use-after-free bugs, replace the VF storage with a combination of a hash
table and krefs to reference track all of the accesses to VFs through
the hash table.

A hash table still allows efficient look up of the VF given its ID, but
also allows adding and removing VFs. It does not require contiguous VF
IDs.

The use of krefs allows the cleanup of the VF memory to be delayed until
after all threads have released their reference (by calling ice_put_vf).

To prevent corruption of the hash table, a combination of RCU and the
mutex table_lock are used. Addition and removal from the hash table use
the RCU-aware hash macros. This allows simple read-only look ups that
iterate to locate a single VF can be fast using RCU. Accesses which
modify the hash table, or which can't take RCU because they sleep, will
hold the mutex lock.

By using this design, we have a stronger guarantee that the VF structure
can't be released until after all threads are finished operating on it.
We also pave the way for the more dynamic Scalable IOV implementation in
the future.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 268 insertions, 108 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c b/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
index 535d5f1a763f..4840570c494d 100644
--- a/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
@@ -182,21 +182,61 @@ struct ice_vsi *ice_get_vf_vsi(struct ice_vf *vf)
  * Locate and return a pointer to the VF structure associated with a given ID.
  * Returns NULL if the ID does not have a valid VF structure associated with
  * it.
+ *
+ * This function takes a reference to the VF, which must be released by
+ * calling ice_put_vf() once the caller is finished accessing the VF structure
+ * returned.
  */
 struct ice_vf *ice_get_vf_by_id(struct ice_pf *pf, u16 vf_id)
 {
-	if (!pf->vfs.table) {
-		dev_err(ice_pf_to_dev(pf), "VF table not allocated\n");
-		return NULL;
-	}
+	struct ice_vf *vf;
 
-	if (vf_id >= pf->vfs.num_alloc) {
-		dev_err(ice_pf_to_dev(pf), "Out of range VF ID: %u\n",
-			vf_id);
-		return NULL;
+	rcu_read_lock();
+	hash_for_each_possible_rcu(pf->vfs.table, vf, entry, vf_id) {
+		if (vf->vf_id == vf_id) {
+			struct ice_vf *found;
+
+			if (kref_get_unless_zero(&vf->refcnt))
+				found = vf;
+			else
+				found = NULL;
+
+			rcu_read_unlock();
+			return found;
+		}
 	}
+	rcu_read_unlock();
+
+	return NULL;
+}
+
+/**
+ * ice_release_vf - Release VF associated with a refcount
+ * @ref: the kref decremented to zero
+ *
+ * Callback function for kref_put to release a VF once its reference count has
+ * hit zero.
+ */
+static void ice_release_vf(struct kref *ref)
+{
+	struct ice_vf *vf = container_of(ref, struct ice_vf, refcnt);
+
+	mutex_destroy(&vf->cfg_lock);
+
+	kfree_rcu(vf, rcu);
+}
 
-	return &pf->vfs.table[vf_id];
+/**
+ * ice_put_vf - Release a reference to a VF
+ * @vf: the VF structure to decrease reference count on
+ *
+ * This must be called after ice_get_vf_by_id() once the reference to the VF
+ * structure is no longer used. Otherwise, the VF structure will never be
+ * freed.
+ */
+void ice_put_vf(struct ice_vf *vf)
+{
+	kref_put(&vf->refcnt, ice_release_vf);
 }
 
 /**
@@ -210,7 +250,10 @@ struct ice_vf *ice_get_vf_by_id(struct ice_pf *pf, u16 vf_id)
  */
 bool ice_has_vfs(struct ice_pf *pf)
 {
-	return pf->vfs.table && pf->vfs.num_alloc > 0;
+	/* A simple check that the hash table is not empty does not require
+	 * the mutex or rcu_read_lock.
+	 */
+	return !hash_empty(pf->vfs.table);
 }
 
 /**
@@ -223,10 +266,16 @@ bool ice_has_vfs(struct ice_pf *pf)
  */
 u16 ice_get_num_vfs(struct ice_pf *pf)
 {
-	if (!pf->vfs.table)
-		return 0;
+	struct ice_vf *vf;
+	unsigned int bkt;
+	u16 num_vfs = 0;
+
+	rcu_read_lock();
+	ice_for_each_vf_rcu(pf, bkt, vf)
+		num_vfs++;
+	rcu_read_unlock();
 
-	return pf->vfs.num_alloc;
+	return num_vfs;
 }
 
 /**
@@ -245,6 +294,32 @@ static int ice_check_vf_init(struct ice_pf *pf, struct ice_vf *vf)
 }
 
 /**
+ * ice_free_vf_entries - Free all VF entries from the hash table
+ * @pf: pointer to the PF structure
+ *
+ * Iterate over the VF hash table, removing and releasing all VF entries.
+ * Called during VF teardown or as cleanup during failed VF initialization.
+ */
+static void ice_free_vf_entries(struct ice_pf *pf)
+{
+	struct ice_vfs *vfs = &pf->vfs;
+	struct hlist_node *tmp;
+	struct ice_vf *vf;
+	unsigned int bkt;
+
+	/* Remove all VFs from the hash table and release their main
+	 * reference. Once all references to the VF are dropped, ice_put_vf()
+	 * will call ice_release_vf which will remove the VF memory.
+	 */
+	lockdep_assert_held(&vfs->table_lock);
+
+	hash_for_each_safe(vfs->table, bkt, tmp, vf, entry) {
+		hash_del_rcu(&vf->entry);
+		ice_put_vf(vf);
+	}
+}
+
+/**
  * ice_vc_vf_broadcast - Broadcast a message to all VFs on PF
  * @pf: pointer to the PF structure
  * @v_opcode: operation code
@@ -260,6 +335,7 @@ ice_vc_vf_broadcast(struct ice_pf *pf, enum virtchnl_ops v_opcode,
 	struct ice_vf *vf;
 	unsigned int bkt;
 
+	mutex_lock(&pf->vfs.table_lock);
 	ice_for_each_vf(pf, bkt, vf) {
 		/* Not all vfs are enabled so skip the ones that are not */
 		if (!test_bit(ICE_VF_STATE_INIT, vf->vf_states) &&
@@ -272,6 +348,7 @@ ice_vc_vf_broadcast(struct ice_pf *pf, enum virtchnl_ops v_opcode,
 		ice_aq_send_msg_to_vf(hw, vf->vf_id, v_opcode, v_retval, msg,
 				      msglen, NULL);
 	}
+	mutex_unlock(&pf->vfs.table_lock);
 }
 
 /**
@@ -546,8 +623,6 @@ void ice_free_vfs(struct ice_pf *pf)
 	if (!ice_has_vfs(pf))
 		return;
 
-	ice_eswitch_release(pf);
-
 	while (test_and_set_bit(ICE_VF_DIS, pf->state))
 		usleep_range(1000, 2000);
 
@@ -560,6 +635,10 @@ void ice_free_vfs(struct ice_pf *pf)
 	else
 		dev_warn(dev, "VFs are assigned - not disabling SR-IOV\n");
 
+	mutex_lock(&vfs->table_lock);
+
+	ice_eswitch_release(pf);
+
 	ice_for_each_vf(pf, bkt, vf) {
 		mutex_lock(&vf->cfg_lock);
 
@@ -587,17 +666,15 @@ void ice_free_vfs(struct ice_pf *pf)
 				vf->vf_id);
 
 		mutex_unlock(&vf->cfg_lock);
-
-		mutex_destroy(&vf->cfg_lock);
 	}
 
 	if (ice_sriov_free_msix_res(pf))
 		dev_err(dev, "Failed to free MSIX resources used by SR-IOV\n");
 
 	vfs->num_qps_per = 0;
-	vfs->num_alloc = 0;
-	devm_kfree(dev, vfs->table);
-	vfs->table = NULL;
+	ice_free_vf_entries(pf);
+
+	mutex_unlock(&vfs->table_lock);
 
 	clear_bit(ICE_VF_DIS, pf->state);
 	clear_bit(ICE_FLAG_SRIOV_ENA, pf->flags);
@@ -1200,6 +1277,8 @@ static int ice_set_per_vf_res(struct ice_pf *pf, u16 num_vfs)
 	int msix_avail_per_vf, msix_avail_for_sriov;
 	struct device *dev = ice_pf_to_dev(pf);
 
+	lockdep_assert_held(&pf->vfs.table_lock);
+
 	if (!num_vfs || max_valid_res_idx < 0)
 		return -EINVAL;
 
@@ -1507,6 +1586,8 @@ bool ice_reset_all_vfs(struct ice_pf *pf, bool is_vflr)
 	if (!ice_has_vfs(pf))
 		return false;
 
+	mutex_lock(&pf->vfs.table_lock);
+
 	/* clear all malicious info if the VFs are getting reset */
 	ice_for_each_vf(pf, bkt, vf)
 		if (ice_mbx_clear_malvf(&hw->mbx_snapshot, pf->vfs.malvfs,
@@ -1515,8 +1596,10 @@ bool ice_reset_all_vfs(struct ice_pf *pf, bool is_vflr)
 				vf->vf_id);
 
 	/* If VFs have been disabled, there is no need to reset */
-	if (test_and_set_bit(ICE_VF_DIS, pf->state))
+	if (test_and_set_bit(ICE_VF_DIS, pf->state)) {
+		mutex_unlock(&pf->vfs.table_lock);
 		return false;
+	}
 
 	/* Begin reset on all VFs at once */
 	ice_for_each_vf(pf, bkt, vf)
@@ -1583,6 +1666,8 @@ bool ice_reset_all_vfs(struct ice_pf *pf, bool is_vflr)
 	ice_flush(hw);
 	clear_bit(ICE_VF_DIS, pf->state);
 
+	mutex_unlock(&pf->vfs.table_lock);
+
 	return true;
 }
 
@@ -1735,8 +1820,10 @@ void ice_vc_notify_link_state(struct ice_pf *pf)
 	struct ice_vf *vf;
 	unsigned int bkt;
 
+	mutex_lock(&pf->vfs.table_lock);
 	ice_for_each_vf(pf, bkt, vf)
 		ice_vc_notify_vf_link_state(vf);
+	mutex_unlock(&pf->vfs.table_lock);
 }
 
 /**
@@ -1855,6 +1942,8 @@ static int ice_start_vfs(struct ice_pf *pf)
 	struct ice_vf *vf;
 	int retval;
 
+	lockdep_assert_held(&pf->vfs.table_lock);
+
 	it_cnt = 0;
 	ice_for_each_vf(pf, bkt, vf) {
 		ice_clear_vf_reset_trigger(vf);
@@ -1889,18 +1978,38 @@ teardown:
 }
 
 /**
- * ice_set_dflt_settings_vfs - set VF defaults during initialization/creation
- * @pf: PF holding reference to all VFs for default configuration
+ * ice_create_vf_entries - Allocate and insert VF entries
+ * @pf: pointer to the PF structure
+ * @num_vfs: the number of VFs to allocate
+ *
+ * Allocate new VF entries and insert them into the hash table. Set some
+ * basic default fields for initializing the new VFs.
+ *
+ * After this function exits, the hash table will have num_vfs entries
+ * inserted.
+ *
+ * Returns 0 on success or an integer error code on failure.
  */
-static void ice_set_dflt_settings_vfs(struct ice_pf *pf)
+static int ice_create_vf_entries(struct ice_pf *pf, u16 num_vfs)
 {
+	struct ice_vfs *vfs = &pf->vfs;
 	struct ice_vf *vf;
-	unsigned int bkt;
-	u16 vf_id = 0;
+	u16 vf_id;
+	int err;
+
+	lockdep_assert_held(&vfs->table_lock);
+
+	for (vf_id = 0; vf_id < num_vfs; vf_id++) {
+		vf = kzalloc(sizeof(*vf), GFP_KERNEL);
+		if (!vf) {
+			err = -ENOMEM;
+			goto err_free_entries;
+		}
+		kref_init(&vf->refcnt);
 
-	ice_for_each_vf(pf, bkt, vf) {
 		vf->pf = pf;
-		vf->vf_id = vf_id++;
+		vf->vf_id = vf_id;
+
 		vf->vf_sw_id = pf->first_sw;
 		/* assign default capabilities */
 		set_bit(ICE_VIRTCHNL_VF_CAP_L2, &vf->vf_caps);
@@ -1917,27 +2026,15 @@ static void ice_set_dflt_settings_vfs(struct ice_pf *pf)
 		ice_vc_set_dflt_vf_ops(&vf->vc_ops);
 
 		mutex_init(&vf->cfg_lock);
-	}
-}
 
-/**
- * ice_alloc_vfs - allocate num_vfs in the PF structure
- * @pf: PF to store the allocated VFs in
- * @num_vfs: number of VFs to allocate
- */
-static int ice_alloc_vfs(struct ice_pf *pf, int num_vfs)
-{
-	struct ice_vf *vfs;
-
-	vfs = devm_kcalloc(ice_pf_to_dev(pf), num_vfs, sizeof(*vfs),
-			   GFP_KERNEL);
-	if (!vfs)
-		return -ENOMEM;
-
-	pf->vfs.table = NULL;
-	pf->vfs.num_alloc = num_vfs;
+		hash_add_rcu(vfs->table, &vf->entry, vf_id);
+	}
 
 	return 0;
+
+err_free_entries:
+	ice_free_vf_entries(pf);
+	return err;
 }
 
 /**
@@ -1958,14 +2055,10 @@ static int ice_ena_vfs(struct ice_pf *pf, u16 num_vfs)
 	ice_flush(hw);
 
 	ret = pci_enable_sriov(pf->pdev, num_vfs);
-	if (ret) {
-		pf->vfs.num_alloc = 0;
+	if (ret)
 		goto err_unroll_intr;
-	}
 
-	ret = ice_alloc_vfs(pf, num_vfs);
-	if (ret)
-		goto err_pci_disable_sriov;
+	mutex_lock(&pf->vfs.table_lock);
 
 	if (ice_set_per_vf_res(pf, num_vfs)) {
 		dev_err(dev, "Not enough resources for %d VFs, try with fewer number of VFs\n",
@@ -1974,12 +2067,17 @@ static int ice_ena_vfs(struct ice_pf *pf, u16 num_vfs)
 		goto err_unroll_sriov;
 	}
 
-	ice_set_dflt_settings_vfs(pf);
+	ret = ice_create_vf_entries(pf, num_vfs);
+	if (ret) {
+		dev_err(dev, "Failed to allocate VF entries for %d VFs\n",
+			num_vfs);
+		goto err_unroll_sriov;
+	}
 
 	if (ice_start_vfs(pf)) {
 		dev_err(dev, "Failed to start VF(s)\n");
 		ret = -EAGAIN;
-		goto err_unroll_sriov;
+		goto err_unroll_vf_entries;
 	}
 
 	clear_bit(ICE_VF_DIS, pf->state);
@@ -1992,13 +2090,14 @@ static int ice_ena_vfs(struct ice_pf *pf, u16 num_vfs)
 	if (test_and_clear_bit(ICE_OICR_INTR_DIS, pf->state))
 		ice_irq_dynamic_ena(hw, NULL, NULL);
 
+	mutex_unlock(&pf->vfs.table_lock);
+
 	return 0;
 
+err_unroll_vf_entries:
+	ice_free_vf_entries(pf);
 err_unroll_sriov:
-	devm_kfree(dev, pf->vfs.table);
-	pf->vfs.table = NULL;
-	pf->vfs.num_alloc = 0;
-err_pci_disable_sriov:
+	mutex_unlock(&pf->vfs.table_lock);
 	pci_disable_sriov(pf->pdev);
 err_unroll_intr:
 	/* rearm interrupts here */
@@ -2133,6 +2232,7 @@ void ice_process_vflr_event(struct ice_pf *pf)
 	    !ice_has_vfs(pf))
 		return;
 
+	mutex_lock(&pf->vfs.table_lock);
 	ice_for_each_vf(pf, bkt, vf) {
 		u32 reg_idx, bit_idx;
 
@@ -2147,6 +2247,7 @@ void ice_process_vflr_event(struct ice_pf *pf)
 			mutex_unlock(&vf->cfg_lock);
 		}
 	}
+	mutex_unlock(&pf->vfs.table_lock);
 }
 
 /**
@@ -2166,22 +2267,36 @@ static void ice_vc_reset_vf(struct ice_vf *vf)
  *
  * If no VF is found who owns the pfq then return NULL, otherwise return a
  * pointer to the VF who owns the pfq
+ *
+ * If this function returns non-NULL, it acquires a reference count of the VF
+ * structure. The caller is responsible for calling ice_put_vf() to drop this
+ * reference.
  */
 static struct ice_vf *ice_get_vf_from_pfq(struct ice_pf *pf, u16 pfq)
 {
 	struct ice_vf *vf;
 	unsigned int bkt;
 
-	ice_for_each_vf(pf, bkt, vf) {
+	rcu_read_lock();
+	ice_for_each_vf_rcu(pf, bkt, vf) {
 		struct ice_vsi *vsi;
 		u16 rxq_idx;
 
 		vsi = ice_get_vf_vsi(vf);
 
 		ice_for_each_rxq(vsi, rxq_idx)
-			if (vsi->rxq_map[rxq_idx] == pfq)
-				return vf;
+			if (vsi->rxq_map[rxq_idx] == pfq) {
+				struct ice_vf *found;
+
+				if (kref_get_unless_zero(&vf->refcnt))
+					found = vf;
+				else
+					found = NULL;
+				rcu_read_unlock();
+				return found;
+			}
 	}
+	rcu_read_unlock();
 
 	return NULL;
 }
@@ -2225,6 +2340,8 @@ ice_vf_lan_overflow_event(struct ice_pf *pf, struct ice_rq_event_info *event)
 	mutex_lock(&vf->cfg_lock);
 	ice_vc_reset_vf(vf);
 	mutex_unlock(&vf->cfg_lock);
+
+	ice_put_vf(vf);
 }
 
 /**
@@ -3008,24 +3125,27 @@ int ice_set_vf_spoofchk(struct net_device *netdev, int vf_id, bool ena)
 
 	ret = ice_check_vf_ready_for_cfg(vf);
 	if (ret)
-		return ret;
+		goto out_put_vf;
 
 	vf_vsi = ice_get_vf_vsi(vf);
 	if (!vf_vsi) {
 		netdev_err(netdev, "VSI %d for VF %d is null\n",
 			   vf->lan_vsi_idx, vf->vf_id);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_put_vf;
 	}
 
 	if (vf_vsi->type != ICE_VSI_VF) {
 		netdev_err(netdev, "Type %d of VSI %d for VF %d is no ICE_VSI_VF\n",
 			   vf_vsi->type, vf_vsi->vsi_num, vf->vf_id);
-		return -ENODEV;
+		ret = -ENODEV;
+		goto out_put_vf;
 	}
 
 	if (ena == vf->spoofchk) {
 		dev_dbg(dev, "VF spoofchk already %s\n", ena ? "ON" : "OFF");
-		return 0;
+		ret = 0;
+		goto out_put_vf;
 	}
 
 	if (ena)
@@ -3038,6 +3158,8 @@ int ice_set_vf_spoofchk(struct net_device *netdev, int vf_id, bool ena)
 	else
 		vf->spoofchk = ena;
 
+out_put_vf:
+	ice_put_vf(vf);
 	return ret;
 }
 
@@ -3050,17 +3172,22 @@ int ice_set_vf_spoofchk(struct net_device *netdev, int vf_id, bool ena)
  */
 bool ice_is_any_vf_in_promisc(struct ice_pf *pf)
 {
+	bool is_vf_promisc = false;
 	struct ice_vf *vf;
 	unsigned int bkt;
 
-	ice_for_each_vf(pf, bkt, vf) {
+	rcu_read_lock();
+	ice_for_each_vf_rcu(pf, bkt, vf) {
 		/* found a VF that has promiscuous mode configured */
 		if (test_bit(ICE_VF_STATE_UC_PROMISC, vf->vf_states) ||
-		    test_bit(ICE_VF_STATE_MC_PROMISC, vf->vf_states))
-			return true;
+		    test_bit(ICE_VF_STATE_MC_PROMISC, vf->vf_states)) {
+			is_vf_promisc = true;
+			break;
+		}
 	}
+	rcu_read_unlock();
 
-	return false;
+	return is_vf_promisc;
 }
 
 /**
@@ -4212,7 +4339,7 @@ ice_set_vf_port_vlan(struct net_device *netdev, int vf_id, u16 vlan_id, u8 qos,
 
 	ret = ice_check_vf_ready_for_cfg(vf);
 	if (ret)
-		return ret;
+		goto out_put_vf;
 
 	if (ice_vf_get_port_vlan_prio(vf) == qos &&
 	    ice_vf_get_port_vlan_tpid(vf) == local_vlan_proto &&
@@ -4220,7 +4347,8 @@ ice_set_vf_port_vlan(struct net_device *netdev, int vf_id, u16 vlan_id, u8 qos,
 		/* duplicate request, so just return success */
 		dev_dbg(dev, "Duplicate port VLAN %u, QoS %u, TPID 0x%04x request\n",
 			vlan_id, qos, local_vlan_proto);
-		return 0;
+		ret = 0;
+		goto out_put_vf;
 	}
 
 	mutex_lock(&vf->cfg_lock);
@@ -4235,7 +4363,9 @@ ice_set_vf_port_vlan(struct net_device *netdev, int vf_id, u16 vlan_id, u8 qos,
 	ice_vc_reset_vf(vf);
 	mutex_unlock(&vf->cfg_lock);
 
-	return 0;
+out_put_vf:
+	ice_put_vf(vf);
+	return ret;
 }
 
 /**
@@ -5786,6 +5916,7 @@ void ice_vc_process_vf_msg(struct ice_pf *pf, struct ice_rq_event_info *event)
 		ice_vc_send_msg_to_vf(vf, v_opcode,
 				      VIRTCHNL_STATUS_ERR_NOT_SUPPORTED, NULL,
 				      0);
+		ice_put_vf(vf);
 		return;
 	}
 
@@ -5795,6 +5926,7 @@ error_handler:
 				      NULL, 0);
 		dev_err(dev, "Invalid message from VF %d, opcode %d, len %d, error %d\n",
 			vf_id, v_opcode, msglen, err);
+		ice_put_vf(vf);
 		return;
 	}
 
@@ -5804,6 +5936,7 @@ error_handler:
 	if (!mutex_trylock(&vf->cfg_lock)) {
 		dev_info(dev, "VF %u is being configured in another context that will trigger a VFR, so there is no need to handle this message\n",
 			 vf->vf_id);
+		ice_put_vf(vf);
 		return;
 	}
 
@@ -5918,6 +6051,7 @@ error_handler:
 	}
 
 	mutex_unlock(&vf->cfg_lock);
+	ice_put_vf(vf);
 }
 
 /**
@@ -5941,7 +6075,7 @@ ice_get_vf_cfg(struct net_device *netdev, int vf_id, struct ifla_vf_info *ivi)
 
 	ret = ice_check_vf_ready_for_cfg(vf);
 	if (ret)
-		return ret;
+		goto out_put_vf;
 
 	ivi->vf = vf_id;
 	ether_addr_copy(ivi->mac, vf->hw_lan_addr.addr);
@@ -5962,7 +6096,10 @@ ice_get_vf_cfg(struct net_device *netdev, int vf_id, struct ifla_vf_info *ivi)
 		ivi->linkstate = IFLA_VF_LINK_STATE_DISABLE;
 	ivi->max_tx_rate = vf->max_tx_rate;
 	ivi->min_tx_rate = vf->min_tx_rate;
-	return 0;
+
+out_put_vf:
+	ice_put_vf(vf);
+	return ret;
 }
 
 /**
@@ -6023,17 +6160,20 @@ int ice_set_vf_mac(struct net_device *netdev, int vf_id, u8 *mac)
 
 	/* nothing left to do, unicast MAC already set */
 	if (ether_addr_equal(vf->dev_lan_addr.addr, mac) &&
-	    ether_addr_equal(vf->hw_lan_addr.addr, mac))
-		return 0;
+	    ether_addr_equal(vf->hw_lan_addr.addr, mac)) {
+		ret = 0;
+		goto out_put_vf;
+	}
 
 	ret = ice_check_vf_ready_for_cfg(vf);
 	if (ret)
-		return ret;
+		goto out_put_vf;
 
 	if (ice_unicast_mac_exists(pf, mac)) {
 		netdev_err(netdev, "Unicast MAC %pM already exists on this PF. Preventing setting VF %u unicast MAC address to %pM\n",
 			   mac, vf_id, mac);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_put_vf;
 	}
 
 	mutex_lock(&vf->cfg_lock);
@@ -6057,7 +6197,10 @@ int ice_set_vf_mac(struct net_device *netdev, int vf_id, u8 *mac)
 
 	ice_vc_reset_vf(vf);
 	mutex_unlock(&vf->cfg_lock);
-	return 0;
+
+out_put_vf:
+	ice_put_vf(vf);
+	return ret;
 }
 
 /**
@@ -6085,11 +6228,13 @@ int ice_set_vf_trust(struct net_device *netdev, int vf_id, bool trusted)
 
 	ret = ice_check_vf_ready_for_cfg(vf);
 	if (ret)
-		return ret;
+		goto out_put_vf;
 
 	/* Check if already trusted */
-	if (trusted == vf->trusted)
-		return 0;
+	if (trusted == vf->trusted) {
+		ret = 0;
+		goto out_put_vf;
+	}
 
 	mutex_lock(&vf->cfg_lock);
 
@@ -6100,7 +6245,9 @@ int ice_set_vf_trust(struct net_device *netdev, int vf_id, bool trusted)
 
 	mutex_unlock(&vf->cfg_lock);
 
-	return 0;
+out_put_vf:
+	ice_put_vf(vf);
+	return ret;
 }
 
 /**
@@ -6123,7 +6270,7 @@ int ice_set_vf_link_state(struct net_device *netdev, int vf_id, int link_state)
 
 	ret = ice_check_vf_ready_for_cfg(vf);
 	if (ret)
-		return ret;
+		goto out_put_vf;
 
 	switch (link_state) {
 	case IFLA_VF_LINK_STATE_AUTO:
@@ -6138,12 +6285,15 @@ int ice_set_vf_link_state(struct net_device *netdev, int vf_id, int link_state)
 		vf->link_up = false;
 		break;
 	default:
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_put_vf;
 	}
 
 	ice_vc_notify_vf_link_state(vf);
 
-	return 0;
+out_put_vf:
+	ice_put_vf(vf);
+	return ret;
 }
 
 /**
@@ -6156,8 +6306,10 @@ static int ice_calc_all_vfs_min_tx_rate(struct ice_pf *pf)
 	unsigned int bkt;
 	int rate = 0;
 
-	ice_for_each_vf(pf, bkt, vf)
+	rcu_read_lock();
+	ice_for_each_vf_rcu(pf, bkt, vf)
 		rate += vf->min_tx_rate;
+	rcu_read_unlock();
 
 	return rate;
 }
@@ -6219,7 +6371,7 @@ ice_set_vf_bw(struct net_device *netdev, int vf_id, int min_tx_rate,
 
 	ret = ice_check_vf_ready_for_cfg(vf);
 	if (ret)
-		return ret;
+		goto out_put_vf;
 
 	vsi = ice_get_vf_vsi(vf);
 
@@ -6229,23 +6381,27 @@ ice_set_vf_bw(struct net_device *netdev, int vf_id, int min_tx_rate,
 	if (max_tx_rate && min_tx_rate > max_tx_rate) {
 		dev_err(dev, "Cannot set min Tx rate %d Mbps greater than max Tx rate %d Mbps\n",
 			min_tx_rate, max_tx_rate);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_put_vf;
 	}
 
 	if (min_tx_rate && ice_is_dcb_active(pf)) {
 		dev_err(dev, "DCB on PF is currently enabled. VF min Tx rate limiting not allowed on this PF.\n");
-		return -EOPNOTSUPP;
+		ret = -EOPNOTSUPP;
+		goto out_put_vf;
 	}
 
-	if (ice_min_tx_rate_oversubscribed(vf, min_tx_rate))
-		return -EINVAL;
+	if (ice_min_tx_rate_oversubscribed(vf, min_tx_rate)) {
+		ret = -EINVAL;
+		goto out_put_vf;
+	}
 
 	if (vf->min_tx_rate != (unsigned int)min_tx_rate) {
 		ret = ice_set_min_bw_limit(vsi, (u64)min_tx_rate * 1000);
 		if (ret) {
 			dev_err(dev, "Unable to set min-tx-rate for VF %d\n",
 				vf->vf_id);
-			return ret;
+			goto out_put_vf;
 		}
 
 		vf->min_tx_rate = min_tx_rate;
@@ -6256,13 +6412,15 @@ ice_set_vf_bw(struct net_device *netdev, int vf_id, int min_tx_rate,
 		if (ret) {
 			dev_err(dev, "Unable to set max-tx-rate for VF %d\n",
 				vf->vf_id);
-			return ret;
+			goto out_put_vf;
 		}
 
 		vf->max_tx_rate = max_tx_rate;
 	}
 
-	return 0;
+out_put_vf:
+	ice_put_vf(vf);
+	return ret;
 }
 
 /**
@@ -6286,11 +6444,13 @@ int ice_get_vf_stats(struct net_device *netdev, int vf_id,
 
 	ret = ice_check_vf_ready_for_cfg(vf);
 	if (ret)
-		return ret;
+		goto out_put_vf;
 
 	vsi = ice_get_vf_vsi(vf);
-	if (!vsi)
-		return -EINVAL;
+	if (!vsi) {
+		ret = -EINVAL;
+		goto out_put_vf;
+	}
 
 	ice_update_eth_stats(vsi);
 	stats = &vsi->eth_stats;
@@ -6308,7 +6468,9 @@ int ice_get_vf_stats(struct net_device *netdev, int vf_id,
 	vf_stats->rx_dropped = stats->rx_discards;
 	vf_stats->tx_dropped = stats->tx_discards;
 
-	return 0;
+out_put_vf:
+	ice_put_vf(vf);
+	return ret;
 }
 
 /**
@@ -6352,6 +6514,7 @@ void ice_print_vfs_mdd_events(struct ice_pf *pf)
 
 	pf->vfs.last_printed_mdd_jiffies = jiffies;
 
+	mutex_lock(&pf->vfs.table_lock);
 	ice_for_each_vf(pf, bkt, vf) {
 		/* only print Rx MDD event message if there are new events */
 		if (vf->mdd_rx_events.count != vf->mdd_rx_events.last_printed) {
@@ -6370,6 +6533,7 @@ void ice_print_vfs_mdd_events(struct ice_pf *pf)
 				 vf->dev_lan_addr.addr);
 		}
 	}
+	mutex_unlock(&pf->vfs.table_lock);
 }
 
 /**
@@ -6425,9 +6589,8 @@ ice_is_malicious_vf(struct ice_pf *pf, struct ice_rq_event_info *event,
 	if (!vf)
 		return false;
 
-	/* Check if VF is disabled. */
 	if (test_bit(ICE_VF_STATE_DIS, vf->vf_states))
-		return false;
+		goto out_put_vf;
 
 	mbxdata.num_msg_proc = num_msg_proc;
 	mbxdata.num_pending_arq = num_msg_pending;
@@ -6438,7 +6601,7 @@ ice_is_malicious_vf(struct ice_pf *pf, struct ice_rq_event_info *event,
 	/* check to see if we have a malicious VF */
 	status = ice_mbx_vf_state_handler(&pf->hw, &mbxdata, vf_id, &malvf);
 	if (status)
-		return false;
+		goto out_put_vf;
 
 	if (malvf) {
 		bool report_vf = false;
@@ -6460,12 +6623,9 @@ ice_is_malicious_vf(struct ice_pf *pf, struct ice_rq_event_info *event,
 					 &vf->dev_lan_addr.addr[0],
 					 pf_vsi->netdev->dev_addr);
 		}
-
-		return true;
 	}
 
-	/* if there was an error in detection or the VF is not malicious then
-	 * return false
-	 */
-	return false;
+out_put_vf:
+	ice_put_vf(vf);
+	return malvf;
 }