package/mac80211/patches/405-b43_locking_fix.patch

   1 Subject: [PATCH] b43: work around a locking issue in ->set_tim()
   2
   3 ops->set_tim() must be atomic, so b43 trying to acquire a mutex leads
   4 to a kernel crash. This patch trades an easy to trigger crash in AP
   5 mode for an unlikely race condition. According to Michael, the real
   6 fix would be to allow set_tim() callbacks to sleep, since b43 is
   7 not the only driver that needs to sleep in all callbacks.
   8
   9 Signed-off-by: Felix Fietkau <nbd@openwrt.org>
  10
  11 --- a/drivers/net/wireless/b43/main.c
  12 +++ b/drivers/net/wireless/b43/main.c
  13 @@ -4534,9 +4534,8 @@ static int b43_op_beacon_set_tim(struct
  14  {
  15         struct b43_wl *wl = hw_to_b43_wl(hw);
  16
  17 -       mutex_lock(&wl->mutex);
  18 +       /* FIXME: add locking */
  19         b43_update_templates(wl);
  20 -       mutex_unlock(&wl->mutex);
  21
  22         return 0;
  23  }