Re: ath: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x02000020DMADBG_7=0x00008040

From: Justin P. Mattock
Date: Sun Mar 25 2012 - 19:00:47 EST

On 03/20/2012 01:29 AM, Sujith Manoharan wrote:
Justin P. Mattock wrote:
yeah this works:

eading symbols from
(gdb) l *(ath_tx_start+0x284)
0xcad4 is in ath_tx_start (drivers/net/wireless/ath/ath9k/xmit.c:1878).
1873 ieee80211_is_data_qos(hdr->frame_control)) {
1874 tidno = ieee80211_get_qos_ctl(hdr)[0]&
1876 tid = ATH_AN_2_TID(txctl->an, tidno);
1878 WARN_ON(tid->ac->txq != txctl->txq);
1879 }
1881 if ((tx_info->flags& IEEE80211_TX_CTL_AMPDU)&& tid) {
1882 /*

Can you try this patch ?

From: Sujith Manoharan<c_manoha@xxxxxxxxxxxxxxxx>
Date: Tue, 20 Mar 2012 13:51:26 +0530
Subject: [PATCH] ath9k: Use HW HT capabilites properly

The commit "ath9k: Remove aggregation flags" changed how
nodes were being initialized. Use the HW HT cap bits
to initialize/de-initialize nodes, else we would be
accessing an uninitialized entry during a suspend/resume cycle,
resulting in a panic.

Reported-by: Justin P. Mattock<justinmattock@xxxxxxxxx>
Signed-off-by: Sujith Manoharan<c_manoha@xxxxxxxxxxxxxxxx>
drivers/net/wireless/ath/ath9k/main.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 3879485..215eb25 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -640,7 +640,7 @@ static void ath_node_attach(struct ath_softc *sc, struct ieee80211_sta *sta,
an->sta = sta;
an->vif = vif;

- if (sta->ht_cap.ht_supported) {
+ if (sc->sc_ah->caps.hw_caps& ATH9K_HW_CAP_HT) {
ath_tx_node_init(sc, an);
an->maxampdu = 1<< (IEEE80211_HT_MAX_AMPDU_FACTOR +
@@ -659,7 +659,7 @@ static void ath_node_detach(struct ath_softc *sc, struct ieee80211_sta *sta)
an->sta = NULL;

- if (sta->ht_cap.ht_supported)
+ if (sc->sc_ah->caps.hw_caps& ATH9K_HW_CAP_HT)
ath_tx_node_cleanup(sc, an);

I would have to say this patch above does get rid of this crash I was seeing. as a quick test I simply connect to a WPA network, then connect to an open network going back and forth triggers this freeze for me after applying this I am able to toggle back and forth without a freeze.


Justin P. Mattock
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