From: nbd <nbd@3c298f89-4303-0410-b956-a3cf2f4a3e73>
Date: Sat, 7 Nov 2009 17:40:52 +0000 (+0000)
Subject: b43: work around a locking issue, might fix #5996
X-Git-Url: http://git.ozo.com/?p=openwrt-10.03%2F.git;a=commitdiff_plain;h=da02086104984438513c27ab0ff21fff81b5ea07

b43: work around a locking issue, might fix #5996

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@18338 3c298f89-4303-0410-b956-a3cf2f4a3e73
---

diff --git a/package/mac80211/patches/405-b43_locking_fix.patch b/package/mac80211/patches/405-b43_locking_fix.patch
new file mode 100644
index 000000000..c90890a7a
--- /dev/null
+++ b/package/mac80211/patches/405-b43_locking_fix.patch
@@ -0,0 +1,23 @@
+Subject: [PATCH] b43: work around a locking issue in ->set_tim()
+
+ops->set_tim() must be atomic, so b43 trying to acquire a mutex leads
+to a kernel crash. This patch trades an easy to trigger crash in AP
+mode for an unlikely race condition. According to Michael, the real
+fix would be to allow set_tim() callbacks to sleep, since b43 is
+not the only driver that needs to sleep in all callbacks.
+
+Signed-off-by: Felix Fietkau <nbd@openwrt.org>
+
+--- a/drivers/net/wireless/b43/main.c
++++ b/drivers/net/wireless/b43/main.c
+@@ -4534,9 +4534,8 @@ static int b43_op_beacon_set_tim(struct 
+ {
+ 	struct b43_wl *wl = hw_to_b43_wl(hw);
+ 
+-	mutex_lock(&wl->mutex);
++	/* FIXME: add locking */
+ 	b43_update_templates(wl);
+-	mutex_unlock(&wl->mutex);
+ 
+ 	return 0;
+ }