From f7969969f416e593bcc7dc24abf3f9fd6c27136d Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 21 Aug 2009 12:23:49 +0200 Subject: cfg80211: make spurious warnings less likely, configurable Bob reported that he got warnings in IBSS mode about the ssid_len being zero on a joined event, but only when kmemcheck was enabled. This appears to be due to a race condition between drivers and userspace, when the driver reports joined but the user in the meantime decided to leave the IBSS again, the warning would trigger. This was made more likely by kmemcheck delaying the code that does the check and sends the event. So first, make the warning trigger closer to the driver, which means it's not locked, but since only the warning depends on it that's ok. And secondly, users will not want to have spurious warnings at all, so make those that are known to be racy in such a way configurable. Reported-by: Bob Copeland Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/wireless/ibss.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'net/wireless/ibss.c') diff --git a/net/wireless/ibss.c b/net/wireless/ibss.c index 42840a01be74..c88338911979 100644 --- a/net/wireless/ibss.c +++ b/net/wireless/ibss.c @@ -22,7 +22,7 @@ void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid) if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC)) return; - if (WARN_ON(!wdev->ssid_len)) + if (!wdev->ssid_len) return; bss = cfg80211_get_bss(wdev->wiphy, NULL, bssid, @@ -58,6 +58,8 @@ void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid, gfp_t gfp) struct cfg80211_event *ev; unsigned long flags; + CFG80211_DEV_WARN_ON(!wdev->ssid_len); + ev = kzalloc(sizeof(*ev), gfp); if (!ev) return; -- cgit v1.2.3