cfg80211: avoid holding the RTNL when calling the driver

Currently, _everything_ in cfg80211 holds the RTNL, and if you
have a slow USB device (or a few) you can get some bad lock
contention on that.

Fix that by re-adding a mutex to each wiphy/rdev as we had at
some point, so we have locking for the wireless_dev lists and
all the other things in there, and also so that drivers still
don't have to worry too much about it (they still won't get
parallel calls for a single device).

Then, we can restrict the RTNL to a few cases where we add or
remove interfaces and really need the added protection. Some
of the global list management still also uses the RTNL, since
we need to have it anyway for netdev management, but we only
hold the RTNL for very short periods of time here.

Link: https://lore.kernel.org/r/20210122161942.81df9f5e047a.I4a8e1a60b18863ea8c5e6d3a0faeafb2d45b2f40@changeid
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> [marvell driver issues]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

39 files changed, 880 insertions, 509 deletions

diff --git a/drivers/net/wireless/ath/ath11k/reg.c b/drivers/net/wireless/ath/ath11k/reg.c
index b876fec7fa1b..e1a1df169034 100644
--- a/drivers/net/wireless/ath/ath11k/reg.c
+++ b/drivers/net/wireless/ath/ath11k/reg.c
@@ -247,7 +247,9 @@ int ath11k_regd_update(struct ath11k *ar, bool init)
 	}
 
 	rtnl_lock();
-	ret = regulatory_set_wiphy_regd_sync_rtnl(ar->hw->wiphy, regd_copy);
+	wiphy_lock(ar->hw->wiphy);
+	ret = regulatory_set_wiphy_regd_sync(ar->hw->wiphy, regd_copy);
+	wiphy_unlock(ar->hw->wiphy);
 	rtnl_unlock();
 
 	kfree(regd_copy);
diff --git a/drivers/net/wireless/ath/ath6kl/core.c b/drivers/net/wireless/ath/ath6kl/core.c
index ebb9f163710f..4f0a7a185fc9 100644
--- a/drivers/net/wireless/ath/ath6kl/core.c
+++ b/drivers/net/wireless/ath/ath6kl/core.c
@@ -212,11 +212,13 @@ int ath6kl_core_init(struct ath6kl *ar, enum ath6kl_htc_type htc_type)
 		ar->avail_idx_map |= BIT(i);
 
 	rtnl_lock();
+	wiphy_lock(ar->wiphy);
 
 	/* Add an initial station interface */
 	wdev = ath6kl_interface_add(ar, "wlan%d", NET_NAME_ENUM,
 				    NL80211_IFTYPE_STATION, 0, INFRA_NETWORK);
 
+	wiphy_unlock(ar->wiphy);
 	rtnl_unlock();
 
 	if (!wdev) {
diff --git a/drivers/net/wireless/ath/ath6kl/init.c b/drivers/net/wireless/ath/ath6kl/init.c
index 39bf19686175..9b5c7d8f2b95 100644
--- a/drivers/net/wireless/ath/ath6kl/init.c
+++ b/drivers/net/wireless/ath/ath6kl/init.c
@@ -1904,7 +1904,9 @@ void ath6kl_stop_txrx(struct ath6kl *ar)
 		spin_unlock_bh(&ar->list_lock);
 		ath6kl_cfg80211_vif_stop(vif, test_bit(WMI_READY, &ar->flag));
 		rtnl_lock();
+		wiphy_lock(ar->wiphy);
 		ath6kl_cfg80211_vif_cleanup(vif);
+		wiphy_unlock(ar->wiphy);
 		rtnl_unlock();
 		spin_lock_bh(&ar->list_lock);
 	}
diff --git a/drivers/net/wireless/ath/wil6210/cfg80211.c b/drivers/net/wireless/ath/wil6210/cfg80211.c
index 1c42410d68e1..60bba5b491e0 100644
--- a/drivers/net/wireless/ath/wil6210/cfg80211.c
+++ b/drivers/net/wireless/ath/wil6210/cfg80211.c
@@ -2820,7 +2820,9 @@ void wil_p2p_wdev_free(struct wil6210_priv *wil)
 	wil->radio_wdev = wil->main_ndev->ieee80211_ptr;
 	mutex_unlock(&wil->vif_mutex);
 	if (p2p_wdev) {
+		wiphy_lock(wil->wiphy);
 		cfg80211_unregister_wdev(p2p_wdev);
+		wiphy_unlock(wil->wiphy);
 		kfree(p2p_wdev);
 	}
 }
diff --git a/drivers/net/wireless/ath/wil6210/netdev.c b/drivers/net/wireless/ath/wil6210/netdev.c
index 472fe804203d..0913f0bf60e7 100644
--- a/drivers/net/wireless/ath/wil6210/netdev.c
+++ b/drivers/net/wireless/ath/wil6210/netdev.c
@@ -473,7 +473,9 @@ int wil_if_add(struct wil6210_priv *wil)
 	wil_update_net_queues_bh(wil, vif, NULL, true);
 
 	rtnl_lock();
+	wiphy_lock(wiphy);
 	rc = wil_vif_add(wil, vif);
+	wiphy_unlock(wiphy);
 	rtnl_unlock();
 	if (rc < 0)
 		goto out_wiphy;
@@ -543,15 +545,18 @@ void wil_if_remove(struct wil6210_priv *wil)
 {
 	struct net_device *ndev = wil->main_ndev;
 	struct wireless_dev *wdev = ndev->ieee80211_ptr;
+	struct wiphy *wiphy = wdev->wiphy;
 
 	wil_dbg_misc(wil, "if_remove\n");
 
 	rtnl_lock();
+	wiphy_lock(wiphy);
 	wil_vif_remove(wil, 0);
+	wiphy_unlock(wiphy);
 	rtnl_unlock();
 
 	netif_napi_del(&wil->napi_tx);
 	netif_napi_del(&wil->napi_rx);
 
-	wiphy_unregister(wdev->wiphy);
+	wiphy_unregister(wiphy);
 }
diff --git a/drivers/net/wireless/ath/wil6210/pcie_bus.c b/drivers/net/wireless/ath/wil6210/pcie_bus.c
index c174323c5c0b..ce40d94909ad 100644
--- a/drivers/net/wireless/ath/wil6210/pcie_bus.c
+++ b/drivers/net/wireless/ath/wil6210/pcie_bus.c
@@ -473,8 +473,10 @@ static void wil_pcie_remove(struct pci_dev *pdev)
 
 	wil6210_debugfs_remove(wil);
 	rtnl_lock();
+	wiphy_lock(wil->wiphy);
 	wil_p2p_wdev_free(wil);
 	wil_remove_all_additional_vifs(wil);
+	wiphy_unlock(wil->wiphy);
 	rtnl_unlock();
 	wil_if_remove(wil);
 	wil_if_pcie_disable(wil);
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
index 6cf308d5934c..ea78fe527c5d 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
@@ -633,7 +633,7 @@ static const struct net_device_ops brcmf_netdev_ops_pri = {
 	.ndo_set_rx_mode = brcmf_netdev_set_multicast_list
 };
 
-int brcmf_net_attach(struct brcmf_if *ifp, bool rtnl_locked)
+int brcmf_net_attach(struct brcmf_if *ifp, bool locked)
 {
 	struct brcmf_pub *drvr = ifp->drvr;
 	struct net_device *ndev;
@@ -656,7 +656,7 @@ int brcmf_net_attach(struct brcmf_if *ifp, bool rtnl_locked)
 	INIT_WORK(&ifp->multicast_work, _brcmf_set_multicast_list);
 	INIT_WORK(&ifp->ndoffload_work, _brcmf_update_ndtable);
 
-	if (rtnl_locked)
+	if (locked)
 		err = cfg80211_register_netdevice(ndev);
 	else
 		err = register_netdev(ndev);
@@ -677,10 +677,10 @@ fail:
 	return -EBADE;
 }
 
-void brcmf_net_detach(struct net_device *ndev, bool rtnl_locked)
+void brcmf_net_detach(struct net_device *ndev, bool locked)
 {
 	if (ndev->reg_state == NETREG_REGISTERED) {
-		if (rtnl_locked)
+		if (locked)
 			cfg80211_unregister_netdevice(ndev);
 		else
 			unregister_netdev(ndev);
@@ -909,7 +909,7 @@ struct brcmf_if *brcmf_add_if(struct brcmf_pub *drvr, s32 bsscfgidx, s32 ifidx,
 }
 
 static void brcmf_del_if(struct brcmf_pub *drvr, s32 bsscfgidx,
-			 bool rtnl_locked)
+			 bool locked)
 {
 	struct brcmf_if *ifp;
 	int ifidx;
@@ -938,7 +938,7 @@ static void brcmf_del_if(struct brcmf_pub *drvr, s32 bsscfgidx,
 			cancel_work_sync(&ifp->multicast_work);
 			cancel_work_sync(&ifp->ndoffload_work);
 		}
-		brcmf_net_detach(ifp->ndev, rtnl_locked);
+		brcmf_net_detach(ifp->ndev, locked);
 	} else {
 		/* Only p2p device interfaces which get dynamically created
 		 * end up here. In this case the p2p module should be informed
@@ -947,7 +947,7 @@ static void brcmf_del_if(struct brcmf_pub *drvr, s32 bsscfgidx,
 		 * serious troublesome side effects. The p2p module will clean
 		 * up the ifp if needed.
 		 */
-		brcmf_p2p_ifp_removed(ifp, rtnl_locked);
+		brcmf_p2p_ifp_removed(ifp, locked);
 		kfree(ifp);
 	}
 
@@ -956,14 +956,14 @@ static void brcmf_del_if(struct brcmf_pub *drvr, s32 bsscfgidx,
 		drvr->if2bss[ifidx] = BRCMF_BSSIDX_INVALID;
 }
 
-void brcmf_remove_interface(struct brcmf_if *ifp, bool rtnl_locked)
+void brcmf_remove_interface(struct brcmf_if *ifp, bool locked)
 {
 	if (!ifp || WARN_ON(ifp->drvr->iflist[ifp->bsscfgidx] != ifp))
 		return;
 	brcmf_dbg(TRACE, "Enter, bsscfgidx=%d, ifidx=%d\n", ifp->bsscfgidx,
 		  ifp->ifidx);
 	brcmf_proto_del_if(ifp->drvr, ifp);
-	brcmf_del_if(ifp->drvr, ifp->bsscfgidx, rtnl_locked);
+	brcmf_del_if(ifp->drvr, ifp->bsscfgidx, locked);
 }
 
 static int brcmf_psm_watchdog_notify(struct brcmf_if *ifp,
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.h
index 5767d665cee5..8212c9de14f1 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.h
@@ -201,16 +201,16 @@ int brcmf_netdev_wait_pend8021x(struct brcmf_if *ifp);
 char *brcmf_ifname(struct brcmf_if *ifp);
 struct brcmf_if *brcmf_get_ifp(struct brcmf_pub *drvr, int ifidx);
 void brcmf_configure_arp_nd_offload(struct brcmf_if *ifp, bool enable);
-int brcmf_net_attach(struct brcmf_if *ifp, bool rtnl_locked);
+int brcmf_net_attach(struct brcmf_if *ifp, bool locked);
 struct brcmf_if *brcmf_add_if(struct brcmf_pub *drvr, s32 bsscfgidx, s32 ifidx,
 			      bool is_p2pdev, const char *name, u8 *mac_addr);
-void brcmf_remove_interface(struct brcmf_if *ifp, bool rtnl_locked);
+void brcmf_remove_interface(struct brcmf_if *ifp, bool locked);
 void brcmf_txflowblock_if(struct brcmf_if *ifp,
 			  enum brcmf_netif_stop_reason reason, bool state);
 void brcmf_txfinalize(struct brcmf_if *ifp, struct sk_buff *txp, bool success);
 void brcmf_netif_rx(struct brcmf_if *ifp, struct sk_buff *skb, bool inirq);
 void brcmf_netif_mon_rx(struct brcmf_if *ifp, struct sk_buff *skb);
-void brcmf_net_detach(struct net_device *ndev, bool rtnl_locked);
+void brcmf_net_detach(struct net_device *ndev, bool locked);
 int brcmf_net_mon_attach(struct brcmf_if *ifp);
 void brcmf_net_setcarrier(struct brcmf_if *ifp, bool on);
 int __init brcmf_core_init(void);
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c
index ec6fc7a150a6..6d30a0fcecea 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c
@@ -2430,7 +2430,7 @@ int brcmf_p2p_del_vif(struct wiphy *wiphy, struct wireless_dev *wdev)
 	return err;
 }
 
-void brcmf_p2p_ifp_removed(struct brcmf_if *ifp, bool rtnl_locked)
+void brcmf_p2p_ifp_removed(struct brcmf_if *ifp, bool locked)
 {
 	struct brcmf_cfg80211_info *cfg;
 	struct brcmf_cfg80211_vif *vif;
@@ -2439,11 +2439,15 @@ void brcmf_p2p_ifp_removed(struct brcmf_if *ifp, bool rtnl_locked)
 	vif = ifp->vif;
 	cfg = wdev_to_cfg(&vif->wdev);
 	cfg->p2p.bss_idx[P2PAPI_BSSCFG_DEVICE].vif = NULL;
-	if (!rtnl_locked)
+	if (locked) {
 		rtnl_lock();
-	cfg80211_unregister_wdev(&vif->wdev);
-	if (!rtnl_locked)
+		wiphy_lock(cfg->wiphy);
+		cfg80211_unregister_wdev(&vif->wdev);
+		wiphy_unlock(cfg->wiphy);
 		rtnl_unlock();
+	} else {
+		cfg80211_unregister_wdev(&vif->wdev);
+	}
 	brcmf_free_vif(vif);
 }
 
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/d3.c b/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
index c025188fa9bc..a0b7331cab31 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
@@ -2143,7 +2143,7 @@ err:
 
 out_iterate:
 	if (!test)
-		ieee80211_iterate_active_interfaces_rtnl(mvm->hw,
+		ieee80211_iterate_active_interfaces_mtx(mvm->hw,
 			IEEE80211_IFACE_ITER_NORMAL,
 			iwl_mvm_d3_disconnect_iter, keep ? vif : NULL);
 
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index da32937ba9a7..6cce72b0685b 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -260,7 +260,7 @@ int iwl_mvm_init_fw_regd(struct iwl_mvm *mvm)
 	int ret;
 	bool changed;
 	const struct ieee80211_regdomain *r =
-			rtnl_dereference(mvm->hw->wiphy->regd);
+			wiphy_dereference(mvm->hw->wiphy, mvm->hw->wiphy->regd);
 
 	if (!r)
 		return -ENOENT;
@@ -282,7 +282,7 @@ int iwl_mvm_init_fw_regd(struct iwl_mvm *mvm)
 
 	/* update cfg80211 if the regdomain was changed */
 	if (changed)
-		ret = regulatory_set_wiphy_regd_sync_rtnl(mvm->hw->wiphy, regd);
+		ret = regulatory_set_wiphy_regd_sync(mvm->hw->wiphy, regd);
 	else
 		ret = 0;
 
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/nvm.c b/drivers/net/wireless/intel/iwlwifi/mvm/nvm.c
index abb8c1088c2f..7fb4e618f76e 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/nvm.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/nvm.c
@@ -545,7 +545,7 @@ int iwl_mvm_init_mcc(struct iwl_mvm *mvm)
 			return -EIO;
 	}
 
-	retval = regulatory_set_wiphy_regd_sync_rtnl(mvm->hw->wiphy, regd);
+	retval = regulatory_set_wiphy_regd_sync(mvm->hw->wiphy, regd);
 	kfree(regd);
 	return retval;
 }
diff --git a/drivers/net/wireless/marvell/mwifiex/cfg80211.c b/drivers/net/wireless/marvell/mwifiex/cfg80211.c
index 15e1cee7f465..5553df913290 100644
--- a/drivers/net/wireless/marvell/mwifiex/cfg80211.c
+++ b/drivers/net/wireless/marvell/mwifiex/cfg80211.c
@@ -2097,7 +2097,7 @@ mwifiex_cfg80211_disconnect(struct wiphy *wiphy, struct net_device *dev,
 	struct mwifiex_private *priv = mwifiex_netdev_get_priv(dev);
 
 	if (!mwifiex_stop_bg_scan(priv))
-		cfg80211_sched_scan_stopped_rtnl(priv->wdev.wiphy, 0);
+		cfg80211_sched_scan_stopped_locked(priv->wdev.wiphy, 0);
 
 	if (mwifiex_deauthenticate(priv, NULL))
 		return -EFAULT;
@@ -2366,7 +2366,7 @@ mwifiex_cfg80211_connect(struct wiphy *wiphy, struct net_device *dev,
 		    (int)sme->ssid_len, (char *)sme->ssid, sme->bssid);
 
 	if (!mwifiex_stop_bg_scan(priv))
-		cfg80211_sched_scan_stopped_rtnl(priv->wdev.wiphy, 0);
+		cfg80211_sched_scan_stopped_locked(priv->wdev.wiphy, 0);
 
 	ret = mwifiex_cfg80211_assoc(priv, sme->ssid_len, sme->ssid, sme->bssid,
 				     priv->bss_mode, sme->channel, sme, 0);
@@ -2576,7 +2576,7 @@ mwifiex_cfg80211_scan(struct wiphy *wiphy,
 		priv->scan_block = false;
 
 	if (!mwifiex_stop_bg_scan(priv))
-		cfg80211_sched_scan_stopped_rtnl(priv->wdev.wiphy, 0);
+		cfg80211_sched_scan_stopped_locked(priv->wdev.wiphy, 0);
 
 	user_scan_cfg = kzalloc(sizeof(*user_scan_cfg), GFP_KERNEL);
 	if (!user_scan_cfg)
diff --git a/drivers/net/wireless/marvell/mwifiex/main.c b/drivers/net/wireless/marvell/mwifiex/main.c
index ee52fb839ef7..529dfd8b7ae8 100644
--- a/drivers/net/wireless/marvell/mwifiex/main.c
+++ b/drivers/net/wireless/marvell/mwifiex/main.c
@@ -598,12 +598,14 @@ static int _mwifiex_fw_dpc(const struct firmware *firmware, void *context)
 	}
 
 	rtnl_lock();
+	wiphy_lock(adapter->wiphy);
 	/* Create station interface by default */
 	wdev = mwifiex_add_virtual_intf(adapter->wiphy, "mlan%d", NET_NAME_ENUM,
 					NL80211_IFTYPE_STATION, NULL);
 	if (IS_ERR(wdev)) {
 		mwifiex_dbg(adapter, ERROR,
 			    "cannot create default STA interface\n");
+		wiphy_unlock(adapter->wiphy);
 		rtnl_unlock();
 		goto err_add_intf;
 	}
@@ -614,6 +616,7 @@ static int _mwifiex_fw_dpc(const struct firmware *firmware, void *context)
 		if (IS_ERR(wdev)) {
 			mwifiex_dbg(adapter, ERROR,
 				    "cannot create AP interface\n");
+			wiphy_unlock(adapter->wiphy);
 			rtnl_unlock();
 			goto err_add_intf;
 		}
@@ -625,10 +628,12 @@ static int _mwifiex_fw_dpc(const struct firmware *firmware, void *context)
 		if (IS_ERR(wdev)) {
 			mwifiex_dbg(adapter, ERROR,
 				    "cannot create p2p client interface\n");
+			wiphy_unlock(adapter->wiphy);
 			rtnl_unlock();
 			goto err_add_intf;
 		}
 	}
+	wiphy_unlock(adapter->wiphy);
 	rtnl_unlock();
 
 	mwifiex_drv_get_driver_version(adapter, fmt, sizeof(fmt) - 1);
@@ -1440,9 +1445,11 @@ static void mwifiex_uninit_sw(struct mwifiex_adapter *adapter)
 		if (!priv)
 			continue;
 		rtnl_lock();
+		wiphy_lock(adapter->wiphy);
 		if (priv->netdev &&
 		    priv->wdev.iftype != NL80211_IFTYPE_UNSPECIFIED)
 			mwifiex_del_virtual_intf(adapter->wiphy, &priv->wdev);
+		wiphy_unlock(adapter->wiphy);
 		rtnl_unlock();
 	}
 
diff --git a/drivers/net/wireless/quantenna/qtnfmac/core.c b/drivers/net/wireless/quantenna/qtnfmac/core.c
index 18964e2a9f28..b4dd60b2ebc9 100644
--- a/drivers/net/wireless/quantenna/qtnfmac/core.c
+++ b/drivers/net/wireless/quantenna/qtnfmac/core.c
@@ -611,8 +611,9 @@ static int qtnf_core_mac_attach(struct qtnf_bus *bus, unsigned int macid)
 	mac->wiphy_registered = 1;
 
 	rtnl_lock();
-
+	wiphy_lock(priv_to_wiphy(mac));
 	ret = qtnf_core_net_attach(mac, vif, "wlan%d", NET_NAME_ENUM);
+	wiphy_unlock(priv_to_wiphy(mac));
 	rtnl_unlock();
 
 	if (ret) {
diff --git a/drivers/net/wireless/virt_wifi.c b/drivers/net/wireless/virt_wifi.c
index c878097f0dda..4b455a4ae15b 100644
--- a/drivers/net/wireless/virt_wifi.c
+++ b/drivers/net/wireless/virt_wifi.c
@@ -537,7 +537,9 @@ static int virt_wifi_newlink(struct net *src_net, struct net_device *dev,
 	dev->ieee80211_ptr->iftype = NL80211_IFTYPE_STATION;
 	dev->ieee80211_ptr->wiphy = common_wiphy;
 
+	wiphy_lock(common_wiphy);
 	err = register_netdevice(dev);
+	wiphy_unlock(common_wiphy);
 	if (err) {
 		dev_err(&priv->lowerdev->dev, "can't register_netdevice: %d\n",
 			err);
@@ -560,7 +562,9 @@ static int virt_wifi_newlink(struct net *src_net, struct net_device *dev,
 
 	return 0;
 unregister_netdev:
+	wiphy_lock(common_wiphy);
 	unregister_netdevice(dev);
+	wiphy_unlock(common_wiphy);
 free_wireless_dev:
 	kfree(dev->ieee80211_ptr);
 	dev->ieee80211_ptr = NULL;
@@ -586,7 +590,9 @@ static void virt_wifi_dellink(struct net_device *dev,
 	netdev_rx_handler_unregister(priv->lowerdev);
 	netdev_upper_dev_unlink(priv->lowerdev, dev);
 
+	wiphy_lock(common_wiphy);
 	unregister_netdevice_queue(dev, head);
+	wiphy_unlock(common_wiphy);
 	module_put(THIS_MODULE);
 
 	/* Deleting the wiphy is handled in the module destructor. */
@@ -625,7 +631,9 @@ static int virt_wifi_event(struct notifier_block *this, unsigned long event,
 		upper_dev = priv->upperdev;
 
 		upper_dev->rtnl_link_ops->dellink(upper_dev, &list_kill);
+		wiphy_lock(common_wiphy);
 		unregister_netdevice_many(&list_kill);
+		wiphy_unlock(common_wiphy);
 		break;
 	}
 
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index e7703fdbac8d..4741d71ead21 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -3632,9 +3632,10 @@ struct mgmt_frame_regs {
  * All callbacks except where otherwise noted should return 0
  * on success or a negative error code.
  *
- * All operations are currently invoked under rtnl for consistency with the
- * wireless extensions but this is subject to reevaluation as soon as this
- * code is used more widely and we have a first user without wext.
+ * All operations are invoked with the wiphy mutex held. The RTNL may be
+ * held in addition (due to wireless extensions) but this cannot be relied
+ * upon except in cases where documented below. Note that due to ordering,
+ * the RTNL also cannot be acquired in any handlers.
  *
  * @suspend: wiphy device needs to be suspended. The variable @wow will
  *	be %NULL or contain the enabled Wake-on-Wireless triggers that are
@@ -3649,11 +3650,14 @@ struct mgmt_frame_regs {
  *	the new netdev in the wiphy's network namespace! Returns the struct
  *	wireless_dev, or an ERR_PTR. For P2P device wdevs, the driver must
  *	also set the address member in the wdev.
+ *	This additionally holds the RTNL to be able to do netdev changes.
  *
  * @del_virtual_intf: remove the virtual interface
+ *	This additionally holds the RTNL to be able to do netdev changes.
  *
  * @change_virtual_intf: change type/configuration of virtual interface,
  *	keep the struct wireless_dev's iftype updated.
+ *	This additionally holds the RTNL to be able to do netdev changes.
  *
  * @add_key: add a key with the given parameters. @mac_addr will be %NULL
  *	when adding a group key.
@@ -4743,6 +4747,7 @@ struct wiphy_iftype_akm_suites {
 
 /**
  * struct wiphy - wireless hardware description
+ * @mtx: mutex for the data (structures) of this device
  * @reg_notifier: the driver's regulatory notification callback,
  *	note that if your driver uses wiphy_apply_custom_regulatory()
  *	the reg_notifier's request can be passed as NULL
@@ -4936,6 +4941,8 @@ struct wiphy_iftype_akm_suites {
  * @sar_capa: SAR control capabilities
  */
 struct wiphy {
+	struct mutex mtx;
+
 	/* assign these fields before you register the wiphy */
 
 	u8 perm_addr[ETH_ALEN];
@@ -5188,6 +5195,37 @@ static inline struct wiphy *wiphy_new(const struct cfg80211_ops *ops,
  */
 int wiphy_register(struct wiphy *wiphy);
 
+/* this is a define for better error reporting (file/line) */
+#define lockdep_assert_wiphy(wiphy) lockdep_assert_held(&(wiphy)->mtx)
+
+/**
+ * rcu_dereference_wiphy - rcu_dereference with debug checking
+ * @wiphy: the wiphy to check the locking on
+ * @p: The pointer to read, prior to dereferencing
+ *
+ * Do an rcu_dereference(p), but check caller either holds rcu_read_lock()
+ * or RTNL. Note: Please prefer wiphy_dereference() or rcu_dereference().
+ */
+#define rcu_dereference_wiphy(wiphy, p)				\
+        rcu_dereference_check(p, lockdep_is_held(&wiphy->mtx))
+
+/**
+ * wiphy_dereference - fetch RCU pointer when updates are prevented by wiphy mtx
+ * @wiphy: the wiphy to check the locking on
+ * @p: The pointer to read, prior to dereferencing
+ *
+ * Return the value of the specified RCU-protected pointer, but omit the
+ * READ_ONCE(), because caller holds the wiphy mutex used for updates.
+ */
+#define wiphy_dereference(wiphy, p)				\
+        rcu_dereference_protected(p, lockdep_is_held(&wiphy->mtx))
+
+/**
+ * get_wiphy_regdom - get custom regdomain for the given wiphy
+ * @wiphy: the wiphy to get the regdomain from
+ */
+const struct ieee80211_regdomain *get_wiphy_regdom(struct wiphy *wiphy);
+
 /**
  * wiphy_unregister - deregister a wiphy from cfg80211
  *
@@ -5213,13 +5251,45 @@ struct cfg80211_cached_keys;
 struct cfg80211_cqm_config;
 
 /**
+ * wiphy_lock - lock the wiphy
+ * @wiphy: the wiphy to lock
+ *
+ * This is mostly exposed so it can be done around registering and
+ * unregistering netdevs that aren't created through cfg80211 calls,
+ * since that requires locking in cfg80211 when the notifiers is
+ * called, but that cannot differentiate which way it's called.
+ *
+ * When cfg80211 ops are called, the wiphy is already locked.
+ */
+static inline void wiphy_lock(struct wiphy *wiphy)
+	__acquires(&wiphy->mtx)
+{
+	mutex_lock(&wiphy->mtx);
+	__acquire(&wiphy->mtx);
+}
+
+/**
+ * wiphy_unlock - unlock the wiphy again
+ * @wiphy: the wiphy to unlock
+ */
+static inline void wiphy_unlock(struct wiphy *wiphy)
+	__releases(&wiphy->mtx)
+{
+	__release(&wiphy->mtx);
+	mutex_unlock(&wiphy->mtx);
+}
+
+/**
  * struct wireless_dev - wireless device state
  *
  * For netdevs, this structure must be allocated by the driver
  * that uses the ieee80211_ptr field in struct net_device (this
  * is intentional so it can be allocated along with the netdev.)
  * It need not be registered then as netdev registration will
- * be intercepted by cfg80211 to see the new wireless device.
+ * be intercepted by cfg80211 to see the new wireless device,
+ * however, drivers must lock the wiphy before registering or
+ * unregistering netdevs if they pre-create any netdevs (in ops
+ * called from cfg80211, the wiphy is already locked.)
  *
  * For non-netdev uses, it must also be allocated by the driver
  * in response to the cfg80211 callbacks that require it, as
@@ -5981,18 +6051,18 @@ int regulatory_set_wiphy_regd(struct wiphy *wiphy,
 			      struct ieee80211_regdomain *rd);
 
 /**
- * regulatory_set_wiphy_regd_sync_rtnl - set regdom for self-managed drivers
+ * regulatory_set_wiphy_regd_sync - set regdom for self-managed drivers
  * @wiphy: the wireless device we want to process the regulatory domain on
  * @rd: the regulatory domain information to use for this wiphy
  *
- * This functions requires the RTNL to be held and applies the new regdomain
- * synchronously to this wiphy. For more details see
- * regulatory_set_wiphy_regd().
+ * This functions requires the RTNL and the wiphy mutex to be held and
+ * applies the new regdomain synchronously to this wiphy. For more details
+ * see regulatory_set_wiphy_regd().
  *
  * Return: 0 on success. -EINVAL, -EPERM
  */
-int regulatory_set_wiphy_regd_sync_rtnl(struct wiphy *wiphy,
-					struct ieee80211_regdomain *rd);
+int regulatory_set_wiphy_regd_sync(struct wiphy *wiphy,
+				   struct ieee80211_regdomain *rd);
 
 /**
  * wiphy_apply_custom_regulatory - apply a custom driver regulatory domain
@@ -6110,7 +6180,7 @@ void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid);
 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid);
 
 /**
- * cfg80211_sched_scan_stopped_rtnl - notify that the scheduled scan has stopped
+ * cfg80211_sched_scan_stopped_locked - notify that the scheduled scan has stopped
  *
  * @wiphy: the wiphy on which the scheduled scan stopped
  * @reqid: identifier for the related scheduled scan request
@@ -6118,9 +6188,9 @@ void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid);
  * The driver can call this function to inform cfg80211 that the
  * scheduled scan had to be stopped, for whatever reason.  The driver
  * is then called back via the sched_scan_stop operation when done.
- * This function should be called with rtnl locked.
+ * This function should be called with the wiphy mutex held.
  */
-void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy, u64 reqid);
+void cfg80211_sched_scan_stopped_locked(struct wiphy *wiphy, u64 reqid);
 
 /**
  * cfg80211_inform_bss_frame_data - inform cfg80211 of a received BSS frame
@@ -7557,7 +7627,7 @@ bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
  * also checks if IR-relaxation conditions apply, to allow beaconing under
  * more permissive conditions.
  *
- * Requires the RTNL to be held.
+ * Requires the