From: Senthil Balasubramanian Date: Mon, 1 Sep 2008 14:28:20 +0000 (+0530) Subject: ath9: Fix ath_rx_flush_tid() for IRQs disabled kernel warning message. X-Git-Tag: v2.6.27-rc6~49^2~3 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=773b4e02be28220e9ead80a5fdb180031361439a;p=linux-2.6-omap-h63xx.git ath9: Fix ath_rx_flush_tid() for IRQs disabled kernel warning message. This patch addresses an issue with the locking order. ath_rx_flush_tid() uses spin_lock/unlock_bh when IRQs are disabled in sta_notify by mac80211. As node clean up is still pending with ath9k and this problematic portion of the code is expected to change anyway, thinking of a proper fix may not be worthwhile. So having this interim fix helps the users to get rid of the kernel warning message. Pasted the kernel warning message for reference. kernel: ath0: No ProbeResp from current AP 00:1b:11:60:7a:3d - assume out of range kernel: ------------[ cut here ]------------ kernel: WARNING: at kernel/softirq.c:136 local_bh_enable+0x3c/0xab() kernel: Pid: 1029, comm: ath9k Not tainted 2.6.27-rc4-wt-w1fi-wl kernel: kernel: Call Trace: kernel: [] warn_on_slowpath+0x51/0x77 kernel: [] check_preempt_wakeup+0xf3/0x123 kernel: [] autoremove_wake_function+0x9/0x2e kernel: [] local_bh_enable+0x3c/0xab kernel: [] ath_rx_node_cleanup+0x38/0x6e [ath9k] kernel: [] ath_node_detach+0x3b/0xb6 [ath9k] kernel: [] ath9k_sta_notify+0x12b/0x165 [ath9k] kernel: [] queue_work+0x1d/0x49 kernel: [] add_todo+0x70/0x99 [mac80211] kernel: [] __sta_info_unlink+0x16b/0x19e [mac80211] kernel: [] sta_info_unlink+0x18/0x43 [mac80211] kernel: [] ieee80211_associated+0xaa/0x16d [mac80211] kernel: [] ieee80211_sta_work+0x4fb/0x6b4 [mac80211] kernel: [] thread_return+0x30/0xa9 kernel: [] ieee80211_sta_work+0x0/0x6b4 [mac80211] kernel: [] run_workqueue+0xb1/0x17a kernel: [] worker_thread+0xd0/0xdb kernel: [] autoremove_wake_function+0x0/0x2e kernel: [] worker_thread+0x0/0xdb kernel: [] kthread+0x47/0x75 kernel: [] schedule_tail+0x18/0x50 kernel: [] child_rip+0xa/0x11 kernel: [] kthread+0x0/0x75 kernel: [] child_rip+0x0/0x11 kernel: kernel: ---[ end trace e9bb5da661055827 ]--- Signed-off-by: Senthil Balasubramanian Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/ath9k/recv.c b/drivers/net/wireless/ath9k/recv.c index 2fe806175c0..20ddb7acdb9 100644 --- a/drivers/net/wireless/ath9k/recv.c +++ b/drivers/net/wireless/ath9k/recv.c @@ -360,8 +360,9 @@ static void ath_rx_flush_tid(struct ath_softc *sc, struct ath_arx_tid *rxtid, int drop) { struct ath_rxbuf *rxbuf; + unsigned long flag; - spin_lock_bh(&rxtid->tidlock); + spin_lock_irqsave(&rxtid->tidlock, flag); while (rxtid->baw_head != rxtid->baw_tail) { rxbuf = rxtid->rxbuf + rxtid->baw_head; if (!rxbuf->rx_wbuf) { @@ -382,7 +383,7 @@ static void ath_rx_flush_tid(struct ath_softc *sc, INCR(rxtid->baw_head, ATH_TID_MAX_BUFS); INCR(rxtid->seq_next, IEEE80211_SEQ_MAX); } - spin_unlock_bh(&rxtid->tidlock); + spin_unlock_irqrestore(&rxtid->tidlock, flag); } static struct sk_buff *ath_rxbuf_alloc(struct ath_softc *sc,