From 98104fdeda63d57631c9f89e90a7b83b58fcee40 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Sat, 16 Jun 2012 00:19:54 +0200 Subject: [PATCH] cfg80211: add P2P Device abstraction In order to support using a different MAC address for the P2P Device address we must first have a P2P Device abstraction that can be assigned a MAC address. This abstraction will also be useful to support offloading P2P operations to the device, e.g. periodic listen for discoverability. Currently, the driver is responsible for assigning a MAC address to the P2P Device, but this could be changed by allowing a MAC address to be given to the NEW_INTERFACE command. As it has no associated netdev, a P2P Device can only be identified by its wdev identifier but the previous patches allowed using the wdev identifier in various APIs, e.g. remain-on-channel. Signed-off-by: Johannes Berg --- include/linux/nl80211.h | 30 ++++++++++-- include/net/cfg80211.h | 40 +++++++++++++++- net/mac80211/iface.c | 3 ++ net/mac80211/util.c | 2 + net/wireless/chan.c | 7 ++- net/wireless/core.c | 53 ++++++++++++++++++++- net/wireless/mlme.c | 10 ++-- net/wireless/nl80211.c | 122 +++++++++++++++++++++++++++++++++++++++++++++--- net/wireless/util.c | 18 ++++++- 9 files changed, 265 insertions(+), 20 deletions(-) diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h index 2f38788..4584162 100644 --- a/include/linux/nl80211.h +++ b/include/linux/nl80211.h @@ -565,6 +565,14 @@ * %NL80211_ATTR_IFINDEX is now on %NL80211_ATTR_WIPHY_FREQ with * %NL80211_ATTR_WIPHY_CHANNEL_TYPE. * + * @NL80211_CMD_START_P2P_DEVICE: Start the given P2P Device, identified by + * its %NL80211_ATTR_WDEV identifier. It must have been created with + * %NL80211_CMD_NEW_INTERFACE previously. After it has been started, the + * P2P Device can be used for P2P operations, e.g. remain-on-channel and + * public action frame TX. + * @NL80211_CMD_STOP_P2P_DEVICE: Stop the given P2P Device, identified by + * its %NL80211_ATTR_WDEV identifier. + * * @NL80211_CMD_MAX: highest used command number * @__NL80211_CMD_AFTER_LAST: internal use */ @@ -708,6 +716,9 @@ enum nl80211_commands { NL80211_CMD_CH_SWITCH_NOTIFY, + NL80211_CMD_START_P2P_DEVICE, + NL80211_CMD_STOP_P2P_DEVICE, + /* add new commands above here */ /* used to define NL80211_CMD_MAX below */ @@ -1575,6 +1586,10 @@ enum nl80211_attrs { * @NL80211_IFTYPE_MESH_POINT: mesh point * @NL80211_IFTYPE_P2P_CLIENT: P2P client * @NL80211_IFTYPE_P2P_GO: P2P group owner + * @NL80211_IFTYPE_P2P_DEVICE: P2P device interface type, this is not a netdev + * and therefore can't be created in the normal ways, use the + * %NL80211_CMD_START_P2P_DEVICE and %NL80211_CMD_STOP_P2P_DEVICE + * commands to create and destroy one * @NL80211_IFTYPE_MAX: highest interface type number currently defined * @NUM_NL80211_IFTYPES: number of defined interface types * @@ -1593,6 +1608,7 @@ enum nl80211_iftype { NL80211_IFTYPE_MESH_POINT, NL80211_IFTYPE_P2P_CLIENT, NL80211_IFTYPE_P2P_GO, + NL80211_IFTYPE_P2P_DEVICE, /* keep last */ NUM_NL80211_IFTYPES, @@ -2994,12 +3010,18 @@ enum nl80211_ap_sme_features { * @NL80211_FEATURE_CELL_BASE_REG_HINTS: This driver has been tested * to work properly to suppport receiving regulatory hints from * cellular base stations. + * @NL80211_FEATURE_P2P_DEVICE_NEEDS_CHANNEL: If this is set, an active + * P2P Device (%NL80211_IFTYPE_P2P_DEVICE) requires its own channel + * in the interface combinations, even when it's only used for scan + * and remain-on-channel. This could be due to, for example, the + * remain-on-channel implementation requiring a channel context. */ enum nl80211_feature_flags { - NL80211_FEATURE_SK_TX_STATUS = 1 << 0, - NL80211_FEATURE_HT_IBSS = 1 << 1, - NL80211_FEATURE_INACTIVITY_TIMER = 1 << 2, - NL80211_FEATURE_CELL_BASE_REG_HINTS = 1 << 3, + NL80211_FEATURE_SK_TX_STATUS = 1 << 0, + NL80211_FEATURE_HT_IBSS = 1 << 1, + NL80211_FEATURE_INACTIVITY_TIMER = 1 << 2, + NL80211_FEATURE_CELL_BASE_REG_HINTS = 1 << 3, + NL80211_FEATURE_P2P_DEVICE_NEEDS_CHANNEL = 1 << 4, }; /** diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 493fa0c..4c518f1 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1437,7 +1437,8 @@ struct cfg80211_gtk_rekey_data { * @add_virtual_intf: create a new virtual interface with the given name, * must set the struct wireless_dev's iftype. Beware: You must create * the new netdev in the wiphy's network namespace! Returns the struct - * wireless_dev, or an ERR_PTR. + * wireless_dev, or an ERR_PTR. For P2P device wdevs, the driver must + * also set the address member in the wdev. * * @del_virtual_intf: remove the virtual interface * @@ -1616,6 +1617,9 @@ struct cfg80211_gtk_rekey_data { * @get_channel: Get the current operating channel for the virtual interface. * For monitor interfaces, it should return %NULL unless there's a single * current monitoring channel. + * + * @start_p2p_device: Start the given P2P device. + * @stop_p2p_device: Stop the given P2P device. */ struct cfg80211_ops { int (*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow); @@ -1832,6 +1836,11 @@ struct cfg80211_ops { (*get_channel)(struct wiphy *wiphy, struct wireless_dev *wdev, enum nl80211_channel_type *type); + + int (*start_p2p_device)(struct wiphy *wiphy, + struct wireless_dev *wdev); + void (*stop_p2p_device)(struct wiphy *wiphy, + struct wireless_dev *wdev); }; /* @@ -2395,6 +2404,8 @@ struct cfg80211_cached_keys; * @cleanup_work: work struct used for cleanup that can't be done directly * @beacon_interval: beacon interval used on this device for transmitting * beacons, 0 when not valid + * @address: The address for this device, valid only if @netdev is %NULL + * @p2p_started: true if this is a P2P Device that has been started */ struct wireless_dev { struct wiphy *wiphy; @@ -2413,7 +2424,9 @@ struct wireless_dev { struct work_struct cleanup_work; - bool use_4addr; + bool use_4addr, p2p_started; + + u8 address[ETH_ALEN] __aligned(sizeof(u16)); /* currently used for IBSS and SME - might be rearranged later */ u8 ssid[IEEE80211_MAX_SSID_LEN]; @@ -2461,6 +2474,13 @@ struct wireless_dev { #endif }; +static inline u8 *wdev_address(struct wireless_dev *wdev) +{ + if (wdev->netdev) + return wdev->netdev->dev_addr; + return wdev->address; +} + /** * wdev_priv - return wiphy priv from wireless_dev * @@ -3528,6 +3548,22 @@ void cfg80211_ch_switch_notify(struct net_device *dev, int freq, */ u32 cfg80211_calculate_bitrate(struct rate_info *rate); +/** + * cfg80211_unregister_wdev - remove the given wdev + * @wdev: struct wireless_dev to remove + * + * Call this function only for wdevs that have no netdev assigned, + * e.g. P2P Devices. It removes the device from the list so that + * it can no longer be used. It is necessary to call this function + * even when cfg80211 requests the removal of the interface by + * calling the del_virtual_intf() callback. The function must also + * be called when the driver wishes to unregister the wdev, e.g. + * when the device is unbound from the driver. + * + * Requires the RTNL to be held. + */ +void cfg80211_unregister_wdev(struct wireless_dev *wdev); + /* Logging, debugging and troubleshooting/diagnostic helpers. */ /* wiphy_printk helpers, similar to dev_printk */ diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index fbab7a8..366d9d3 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -449,6 +449,7 @@ static int ieee80211_do_open(struct net_device *dev, bool coming_up) case NUM_NL80211_IFTYPES: case NL80211_IFTYPE_P2P_CLIENT: case NL80211_IFTYPE_P2P_GO: + case NL80211_IFTYPE_P2P_DEVICE: /* cannot happen */ WARN_ON(1); break; @@ -1146,6 +1147,8 @@ static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata, case NL80211_IFTYPE_WDS: case NL80211_IFTYPE_AP_VLAN: break; + case NL80211_IFTYPE_P2P_DEVICE: + /* not yet supported */ case NL80211_IFTYPE_UNSPECIFIED: case NUM_NL80211_IFTYPES: BUG(); diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 7dff94e..9a4e4e3 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -1390,6 +1390,8 @@ int ieee80211_reconfig(struct ieee80211_local *local) case NL80211_IFTYPE_MONITOR: /* ignore virtual */ break; + case NL80211_IFTYPE_P2P_DEVICE: + /* not yet supported */ case NL80211_IFTYPE_UNSPECIFIED: case NUM_NL80211_IFTYPES: case NL80211_IFTYPE_P2P_CLIENT: diff --git a/net/wireless/chan.c b/net/wireless/chan.c index d355f67..2f876b9 100644 --- a/net/wireless/chan.c +++ b/net/wireless/chan.c @@ -105,7 +105,7 @@ cfg80211_get_chan_state(struct wireless_dev *wdev, ASSERT_WDEV_LOCK(wdev); - if (!netif_running(wdev->netdev)) + if (wdev->netdev && !netif_running(wdev->netdev)) return; switch (wdev->iftype) { @@ -143,6 +143,11 @@ cfg80211_get_chan_state(struct wireless_dev *wdev, case NL80211_IFTYPE_WDS: /* these interface types don't really have a channel */ return; + case NL80211_IFTYPE_P2P_DEVICE: + if (wdev->wiphy->features & + NL80211_FEATURE_P2P_DEVICE_NEEDS_CHANNEL) + *chanmode = CHAN_MODE_EXCLUSIVE; + return; case NL80211_IFTYPE_UNSPECIFIED: case NUM_NL80211_IFTYPES: WARN_ON(1); diff --git a/net/wireless/core.c b/net/wireless/core.c index 31b40cc..91b3004 100644 --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -230,9 +230,24 @@ static int cfg80211_rfkill_set_block(void *data, bool blocked) rtnl_lock(); mutex_lock(&rdev->devlist_mtx); - list_for_each_entry(wdev, &rdev->wdev_list, list) - if (wdev->netdev) + list_for_each_entry(wdev, &rdev->wdev_list, list) { + if (wdev->netdev) { dev_close(wdev->netdev); + continue; + } + /* otherwise, check iftype */ + switch (wdev->iftype) { + case NL80211_IFTYPE_P2P_DEVICE: + if (!wdev->p2p_started) + break; + rdev->ops->stop_p2p_device(&rdev->wiphy, wdev); + wdev->p2p_started = false; + rdev->opencount--; + break; + default: + break; + } + } mutex_unlock(&rdev->devlist_mtx); rtnl_unlock(); @@ -407,6 +422,11 @@ static int wiphy_verify_combinations(struct wiphy *wiphy) if (WARN_ON(wiphy->software_iftypes & types)) return -EINVAL; + /* Only a single P2P_DEVICE can be allowed */ + if (WARN_ON(types & BIT(NL80211_IFTYPE_P2P_DEVICE) && + c->limits[j].max > 1)) + return -EINVAL; + cnt += c->limits[j].max; /* * Don't advertise an unsupported type @@ -734,6 +754,35 @@ static void wdev_cleanup_work(struct work_struct *work) dev_put(wdev->netdev); } +void cfg80211_unregister_wdev(struct wireless_dev *wdev) +{ + struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy); + + ASSERT_RTNL(); + + if (WARN_ON(wdev->netdev)) + return; + + mutex_lock(&rdev->devlist_mtx); + list_del_rcu(&wdev->list); + rdev->devlist_generation++; + + switch (wdev->iftype) { + case NL80211_IFTYPE_P2P_DEVICE: + if (!wdev->p2p_started) + break; + rdev->ops->stop_p2p_device(&rdev->wiphy, wdev); + wdev->p2p_started = false; + rdev->opencount--; + break; + default: + WARN_ON_ONCE(1); + break; + } + mutex_unlock(&rdev->devlist_mtx); +} +EXPORT_SYMBOL(cfg80211_unregister_wdev); + static struct device_type wiphy_type = { .name = "wlan", }; diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c index 1cdb1d5..8fd0242 100644 --- a/net/wireless/mlme.c +++ b/net/wireless/mlme.c @@ -736,7 +736,6 @@ int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev, const u8 *buf, size_t len, bool no_cck, bool dont_wait_for_ack, u64 *cookie) { - struct net_device *dev = wdev->netdev; const struct ieee80211_mgmt *mgmt; u16 stype; @@ -796,7 +795,7 @@ int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev, case NL80211_IFTYPE_AP: case NL80211_IFTYPE_P2P_GO: case NL80211_IFTYPE_AP_VLAN: - if (!ether_addr_equal(mgmt->bssid, dev->dev_addr)) + if (!ether_addr_equal(mgmt->bssid, wdev_address(wdev))) err = -EINVAL; break; case NL80211_IFTYPE_MESH_POINT: @@ -809,6 +808,11 @@ int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev, * cfg80211 doesn't track the stations */ break; + case NL80211_IFTYPE_P2P_DEVICE: + /* + * fall through, P2P device only supports + * public action frames + */ default: err = -EOPNOTSUPP; break; @@ -819,7 +823,7 @@ int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev, return err; } - if (!ether_addr_equal(mgmt->sa, dev->dev_addr)) + if (!ether_addr_equal(mgmt->sa, wdev_address(wdev))) return -EINVAL; /* Transmit the Action frame as requested by user space */ diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 97026f3..787aeaa 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -1100,6 +1100,7 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags, if (nla_put_u32(msg, i, NL80211_CMD_REGISTER_BEACONS)) goto nla_put_failure; } + CMD(start_p2p_device, START_P2P_DEVICE); #ifdef CONFIG_NL80211_TESTMODE CMD(testmode_cmd, TESTMODE); @@ -1748,13 +1749,13 @@ static int nl80211_send_iface(struct sk_buff *msg, u32 pid, u32 seq, int flags, if (dev && (nla_put_u32(msg, NL80211_ATTR_IFINDEX, dev->ifindex) || - nla_put_string(msg, NL80211_ATTR_IFNAME, dev->name) || - nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, dev->dev_addr))) + nla_put_string(msg, NL80211_ATTR_IFNAME, dev->name))) goto nla_put_failure; if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) || nla_put_u32(msg, NL80211_ATTR_IFTYPE, wdev->iftype) || nla_put_u64(msg, NL80211_ATTR_WDEV, wdev_id(wdev)) || + nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, wdev_address(wdev)) || nla_put_u32(msg, NL80211_ATTR_GENERATION, rdev->devlist_generation ^ (cfg80211_rdev_list_generation << 2))) @@ -2021,8 +2022,10 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info) return PTR_ERR(wdev); } - if (type == NL80211_IFTYPE_MESH_POINT && - info->attrs[NL80211_ATTR_MESH_ID]) { + switch (type) { + case NL80211_IFTYPE_MESH_POINT: + if (!info->attrs[NL80211_ATTR_MESH_ID]) + break; wdev_lock(wdev); BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN != IEEE80211_MAX_MESH_ID_LEN); @@ -2031,6 +2034,26 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info) memcpy(wdev->ssid, nla_data(info->attrs[NL80211_ATTR_MESH_ID]), wdev->mesh_id_up_len); wdev_unlock(wdev); + break; + case NL80211_IFTYPE_P2P_DEVICE: + /* + * P2P Device doesn't have a netdev, so doesn't go + * through the netdev notifier and must be added here + */ + mutex_init(&wdev->mtx); + INIT_LIST_HEAD(&wdev->event_list); + spin_lock_init(&wdev->event_lock); + INIT_LIST_HEAD(&wdev->mgmt_registrations); + spin_lock_init(&wdev->mgmt_registrations_lock); + + mutex_lock(&rdev->devlist_mtx); + wdev->identifier = ++rdev->wdev_id; + list_add_rcu(&wdev->list, &rdev->wdev_list); + rdev->devlist_generation++; + mutex_unlock(&rdev->devlist_mtx); + break; + default: + break; } if (nl80211_send_iface(msg, info->snd_pid, info->snd_seq, 0, @@ -6053,6 +6076,7 @@ static int nl80211_register_mgmt(struct sk_buff *skb, struct genl_info *info) case NL80211_IFTYPE_AP_VLAN: case NL80211_IFTYPE_MESH_POINT: case NL80211_IFTYPE_P2P_GO: + case NL80211_IFTYPE_P2P_DEVICE: break; default: return -EOPNOTSUPP; @@ -6099,6 +6123,7 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info) case NL80211_IFTYPE_AP_VLAN: case NL80211_IFTYPE_MESH_POINT: case NL80211_IFTYPE_P2P_GO: + case NL80211_IFTYPE_P2P_DEVICE: break; default: return -EOPNOTSUPP; @@ -6195,6 +6220,7 @@ static int nl80211_tx_mgmt_cancel_wait(struct sk_buff *skb, struct genl_info *in case NL80211_IFTYPE_AP: case NL80211_IFTYPE_AP_VLAN: case NL80211_IFTYPE_P2P_GO: + case NL80211_IFTYPE_P2P_DEVICE: break; default: return -EOPNOTSUPP; @@ -6810,6 +6836,68 @@ static int nl80211_register_beacons(struct sk_buff *skb, struct genl_info *info) return 0; } +static int nl80211_start_p2p_device(struct sk_buff *skb, struct genl_info *info) +{ + struct cfg80211_registered_device *rdev = info->user_ptr[0]; + struct wireless_dev *wdev = info->user_ptr[1]; + int err; + + if (!rdev->ops->start_p2p_device) + return -EOPNOTSUPP; + + if (wdev->iftype != NL80211_IFTYPE_P2P_DEVICE) + return -EOPNOTSUPP; + + if (wdev->p2p_started) + return 0; + + mutex_lock(&rdev->devlist_mtx); + err = cfg80211_can_add_interface(rdev, wdev->iftype); + mutex_unlock(&rdev->devlist_mtx); + if (err) + return err; + + err = rdev->ops->start_p2p_device(&rdev->wiphy, wdev); + if (err) + return err; + + wdev->p2p_started = true; + mutex_lock(&rdev->devlist_mtx); + rdev->opencount++; + mutex_unlock(&rdev->devlist_mtx); + + return 0; +} + +static int nl80211_stop_p2p_device(struct sk_buff *skb, struct genl_info *info) +{ + struct cfg80211_registered_device *rdev = info->user_ptr[0]; + struct wireless_dev *wdev = info->user_ptr[1]; + + if (wdev->iftype != NL80211_IFTYPE_P2P_DEVICE) + return -EOPNOTSUPP; + + if (!rdev->ops->stop_p2p_device) + return -EOPNOTSUPP; + + if (!wdev->p2p_started) + return 0; + + rdev->ops->stop_p2p_device(&rdev->wiphy, wdev); + wdev->p2p_started = false; + + mutex_lock(&rdev->devlist_mtx); + rdev->opencount--; + mutex_unlock(&rdev->devlist_mtx); + + if (WARN_ON(rdev->scan_req && rdev->scan_req->wdev == wdev)) { + rdev->scan_req->aborted = true; + ___cfg80211_scan_done(rdev, true); + } + + return 0; +} + #define NL80211_FLAG_NEED_WIPHY 0x01 #define NL80211_FLAG_NEED_NETDEV 0x02 #define NL80211_FLAG_NEED_RTNL 0x04 @@ -6817,7 +6905,7 @@ static int nl80211_register_beacons(struct sk_buff *skb, struct genl_info *info) #define NL80211_FLAG_NEED_NETDEV_UP (NL80211_FLAG_NEED_NETDEV |\ NL80211_FLAG_CHECK_NETDEV_UP) #define NL80211_FLAG_NEED_WDEV 0x10 -/* If a netdev is associated, it must be UP */ +/* If a netdev is associated, it must be UP, P2P must be started */ #define NL80211_FLAG_NEED_WDEV_UP (NL80211_FLAG_NEED_WDEV |\ NL80211_FLAG_CHECK_NETDEV_UP) @@ -6878,6 +6966,13 @@ static int nl80211_pre_doit(struct genl_ops *ops, struct sk_buff *skb, } dev_hold(dev); + } else if (ops->internal_flags & NL80211_FLAG_CHECK_NETDEV_UP) { + if (!wdev->p2p_started) { + mutex_unlock(&cfg80211_mutex); + if (rtnl) + rtnl_unlock(); + return -ENETDOWN; + } } cfg80211_lock_rdev(rdev); @@ -7439,7 +7534,22 @@ static struct genl_ops nl80211_ops[] = { .internal_flags = NL80211_FLAG_NEED_NETDEV | NL80211_FLAG_NEED_RTNL, }, - + { + .cmd = NL80211_CMD_START_P2P_DEVICE, + .doit = nl80211_start_p2p_device, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + .internal_flags = NL80211_FLAG_NEED_WDEV | + NL80211_FLAG_NEED_RTNL, + }, + { + .cmd = NL80211_CMD_STOP_P2P_DEVICE, + .doit = nl80211_stop_p2p_device, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + .internal_flags = NL80211_FLAG_NEED_WDEV_UP | + NL80211_FLAG_NEED_RTNL, + }, }; static struct genl_multicast_group nl80211_mlme_mcgrp = { diff --git a/net/wireless/util.c b/net/wireless/util.c index ce393dd..d7b6722 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -800,6 +800,10 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev, if (otype == NL80211_IFTYPE_AP_VLAN) return -EOPNOTSUPP; + /* cannot change into P2P device type */ + if (ntype == NL80211_IFTYPE_P2P_DEVICE) + return -EOPNOTSUPP; + if (!rdev->ops->change_virtual_intf || !(rdev->wiphy.interface_modes & (1 << ntype))) return -EOPNOTSUPP; @@ -877,6 +881,9 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev, case NUM_NL80211_IFTYPES: /* not happening */ break; + case NL80211_IFTYPE_P2P_DEVICE: + WARN_ON(1); + break; } } @@ -1041,8 +1048,15 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev, list_for_each_entry(wdev_iter, &rdev->wdev_list, list) { if (wdev_iter == wdev) continue; - if (!netif_running(wdev_iter->netdev)) - continue; + if (wdev_iter->netdev) { + if (!netif_running(wdev_iter->netdev)) + continue; + } else if (wdev_iter->iftype == NL80211_IFTYPE_P2P_DEVICE) { + if (!wdev_iter->p2p_started) + continue; + } else { + WARN_ON(1); + } if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype)) continue; -- 2.7.4