Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:37441 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757179AbZFJITp (ORCPT ); Wed, 10 Jun 2009 04:19:45 -0400 From: "Luis R. Rodriguez" To: linville@tuxdriver.com, johannes@sipsolutions.net, j@w1.fi Cc: linux-wireless@vger.kernel.org, ath9k-devel@lists.ath9k.org, "Luis R. Rodriguez" Subject: [PATCH 01/18] mac80211: disable moving between PS modes during scan Date: Wed, 10 Jun 2009 04:19:18 -0400 Message-Id: <1244621975-1238-2-git-send-email-lrodriguez@atheros.com> In-Reply-To: <1244621975-1238-1-git-send-email-lrodriguez@atheros.com> References: <1244621975-1238-1-git-send-email-lrodriguez@atheros.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: We don't want to trigger moving between PS mode during scan. With this enabled we sometimes end up sending nullfunc frames during scan. We're supposed to only send one prior to scan and after scan. This fixes an oops which occured due to an assert in ath9k: http://marc.info/?l=linux-wireless&m=124277331319024 The assert was happening because the rate control algorithm figures it should find at least one valid dual stream or single stream rate. Since we allow mac80211 to send nullfunc frames during scan and dynamic PS was enabled at times we ended up trying to send nullfunc frames for the target sta on the wrong band for which we have no valid rate to communicate with it. This brakes the assumptions in rate control. We'll handle this sanity check next, but this fix does prevent the spurious nullfunc frames from actually being sent. Signed-off-by: Luis R. Rodriguez --- net/mac80211/tx.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 1436f74..e43fbb9 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1415,7 +1415,8 @@ int ieee80211_master_start_xmit(struct sk_buff *skb, struct net_device *dev) } if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) && - local->hw.conf.dynamic_ps_timeout > 0) { + local->hw.conf.dynamic_ps_timeout > 0 && + !local->sw_scanning && !local->hw_scanning) { if (local->hw.conf.flags & IEEE80211_CONF_PS) { ieee80211_stop_queues_by_reason(&local->hw, IEEE80211_QUEUE_STOP_REASON_PS); -- 1.6.0.6