Re: Suspicious RCU usage in mac80211

[Larry Finger <Larry.Finger@lwfinger.net>]

On 05/03/2012 03:47 AM, Catalin Marinas wrote:
>
> IIUC, Paul suggested that you should use rcu_dereference_check() here
> instead as the protected one is not safe in this context.

This patch also fails to fix the problem. Did I do what Paul suggested?


Index: wireless-testing-new/net/mac80211/sta_info.h
===================================================================
--- wireless-testing-new.orig/net/mac80211/sta_info.h
+++ wireless-testing-new/net/mac80211/sta_info.h
@@ -452,7 +452,7 @@ void ieee80211_assign_tid_tx(struct sta_
  static inline struct tid_ampdu_tx *
  rcu_dereference_protected_tid_tx(struct sta_info *sta, int tid)
  {
-       return rcu_dereference_protected(sta->ampdu_mlme.tid_tx[tid],
+       return rcu_dereference_check(sta->ampdu_mlme.tid_tx[tid],
                                          lockdep_is_held(&sta->lock) ||
                                          lockdep_is_held(&sta->ampdu_mlme.mtx));
  }