diff options
Diffstat (limited to 'net/mac80211/main.c')
| -rw-r--r-- | net/mac80211/main.c | 33 |
1 files changed, 25 insertions, 8 deletions
diff --git a/net/mac80211/main.c b/net/mac80211/main.c index ebdec7106d63..4bfac4b41c51 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -564,14 +564,6 @@ static int ieee80211_stop(struct net_device *dev) synchronize_rcu(); skb_queue_purge(&sdata->u.sta.skb_queue); - if (local->scan_sdata == sdata) { - if (!local->ops->hw_scan) { - local->sta_sw_scanning = 0; - cancel_delayed_work(&local->scan_work); - } else - local->sta_hw_scanning = 0; - } - sdata->u.sta.flags &= ~IEEE80211_STA_PRIVACY_INVOKED; kfree(sdata->u.sta.extra_ie); sdata->u.sta.extra_ie = NULL; @@ -585,6 +577,31 @@ static int ieee80211_stop(struct net_device *dev) } /* fall through */ default: + if (local->scan_sdata == sdata) { + if (!local->ops->hw_scan) + cancel_delayed_work_sync(&local->scan_work); + /* + * The software scan can no longer run now, so we can + * clear out the scan_sdata reference. However, the + * hardware scan may still be running. The complete + * function must be prepared to handle a NULL value. + */ + local->scan_sdata = NULL; + /* + * The memory barrier guarantees that another CPU + * that is hardware-scanning will now see the fact + * that this interface is gone. + */ + smp_mb(); + /* + * If software scanning, complete the scan but since + * the scan_sdata is NULL already don't send out a + * scan event to userspace -- the scan is incomplete. + */ + if (local->sta_sw_scanning) + ieee80211_scan_completed(&local->hw); + } + conf.vif = &sdata->vif; conf.type = sdata->vif.type; conf.mac_addr = dev->dev_addr; |