[PATCH-mac80211] cfg80211: disable CSA for all drivers

[PATCH-mac80211] cfg80211: disable CSA for all drivers

[Simon Wunderlich]

The channel switch announcement code has some major locking problems
which can cause a deadlock in worst case. A series of fixes has been
proposed, but these are non-trivial and need to be tested first.
Therefore disable CSA completely for 3.13.

Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
This is based on mac80211.git and should go into 3.13 only
---
 net/wireless/core.c |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/wireless/core.c b/net/wireless/core.c
index aff959e..507e71f 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -451,6 +451,12 @@ int wiphy_register(struct wiphy *wiphy)
 	int i;
 	u16 ifmodes = wiphy->interface_modes;
 
+	/*
+	 * There are major locking problems in nl80211/mac80211 for CSA,
+	 * disable for all drivers until this has been reworked.
+	 */
+	wiphy->flags &= ~WIPHY_FLAG_HAS_CHANNEL_SWITCH;
+
 #ifdef CONFIG_PM
 	if (WARN_ON(wiphy->wowlan &&
 		    (wiphy->wowlan->flags & WIPHY_WOWLAN_GTK_REKEY_FAILURE) &&
-- 
1.7.10.4

Re: [PATCH-mac80211] cfg80211: disable CSA for all drivers

[Johannes Berg]

On Tue, 2013-11-26 at 16:07 +0100, Simon Wunderlich wrote:
> The channel switch announcement code has some major locking problems
> which can cause a deadlock in worst case. A series of fixes has been
> proposed, but these are non-trivial and need to be tested first.
> Therefore disable CSA completely for 3.13.
> 
> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
> ---
> This is based on mac80211.git and should go into 3.13 only

It didn't apply cleanly so I guess you didn't base it on the latest
version, but I picked it up.

johannes