Return-path: Received: from wolverine02.qualcomm.com ([199.106.114.251]:7983 "EHLO wolverine02.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751952Ab1LPNHj (ORCPT ); Fri, 16 Dec 2011 08:07:39 -0500 From: Mohammed Shafi Shajakhan To: Felix Fietkau , "John W. Linville" CC: Jouni Malinen , , Rodriguez Luis , Balasubramanian senthilkumar , Vasanthakumar Thiagarajan , Rajkumar Manoharan , Vivek Natarajan , , Mohammed Shafi Shajakhan Subject: [PATCH 1/1] ath9k: fix a soft lockup Date: Fri, 16 Dec 2011 18:35:52 +0530 Message-ID: <1324040752-4583-1-git-send-email-mohammed@qca.qualcomm.com> (sfid-20111216_140747_384223_306247E4) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Mohammed Shafi Shajakhan with the recent changes in the tx path we got a soft lockup. introduced by the commit 3ad2952998b08442044690fa9b4ec38c6c3fc4a9 ath_send_bar seems to later call ath9k_tx which in turn seems to acquire the same axq_lock before calling ath_tx_start_dma Call Trace: [] __delay+0xe/0x10 [] do_raw_spin_lock+0xb2/0x100 [] _raw_spin_lock_bh+0x67/0x80 [] ? ath_tx_start+0x151/0x4c0 [ath9k] [] ath_tx_start+0x151/0x4c0 [ath9k] [] ath9k_tx+0x9c/0x1f0 [ath9k] [] __ieee80211_tx+0x18e/0x2d0 [mac80211] [] ieee80211_tx+0xfc/0x130 [mac80211] [] ? ieee80211_tx+0x33/0x130 [mac80211] [] ieee80211_xmit+0xc8/0x130 [mac80211] [] ? ieee80211_tx_pending+0x2e0/0x2e0 [mac80211] [] ieee80211_tx_skb_tid+0x4d/0x60 [mac80211] [] ieee80211_send_bar+0xd4/0xf0 [mac80211] [] ath_tx_complete_aggr+0x52a/0xaa0 [ath9k] [] ? ath_tx_complete_aggr+0xb0/0xaa0 [ath9k] [] ? setup_ht_cap+0x169/0x180 [ath9k] [] ? ath_tx_edma_tasklet+0x76/0x2a0 [ath9k] [] ? ath_tx_edma_tasklet+0x76/0x2a0 [ath9k] [] ath_tx_process_buffer+0x68/0xe0 [ath9k] [] ath_tx_edma_tasklet+0x175/0x2a0 [ath9k] [] ? ath9k_ioread32+0x2d/0x70 [ath9k] [] ath9k_tasklet+0x10b/0x1c0 [ath9k] Signed-off-by: Mohammed Shafi Shajakhan --- drivers/net/wireless/ath/ath9k/xmit.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index 23e80e6..ef81df0 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -189,8 +189,11 @@ static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid) tid->state &= ~AGGR_CLEANUP; } - if (sendbar) + if (sendbar) { + spin_unlock_bh(&txq->axq_lock); ath_send_bar(tid, tid->seq_start); + spin_lock_bh(&txq->axq_lock); + } } static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid, @@ -556,7 +559,9 @@ static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq, if (bar_index >= 0) { u16 bar_seq = ATH_BA_INDEX2SEQ(seq_first, bar_index); + spin_unlock_bh(&txq->axq_lock); ath_send_bar(tid, ATH_BA_INDEX2SEQ(seq_first, bar_index + 1)); + spin_lock_bh(&txq->axq_lock); if (BAW_WITHIN(tid->seq_start, tid->baw_size, bar_seq)) tid->bar_index = ATH_BA_INDEX(tid->seq_start, bar_seq); } -- 1.7.0.4