From 5d9b6f263995d7f43202d76cf2e23d43f9240a90 Mon Sep 17 00:00:00 2001 From: Mohammed Shafi Shajakhan Date: Tue, 28 Aug 2012 12:14:48 +0530 Subject: ath9k: Fix a crash in 2 WIRE btcoex chipsets Generic timers for BTCOEX functionality is applicable only for 3 WIRE BTCOEX (and MCI) chipsets. Hence btcoex->no_stomp_timer is allocated only 3 WIRE btcoex chipsets and in all the other cases its NULL. Make sure we stop the generic timer only if 'btcoex->hw_timer_enabled' is true(only if its up and running) Fixes the following crash [68757.020454] BUG: unable to handle kernel NULL pointer dereference at 0000000c [68757.020916] IP: [] ath9k_hw_gen_timer_stop+0x13/0x80 [ath9k_hw] [68757.021251] *pde = 00000000 [68757.024384] EIP: 0060:[] EFLAGS: 00010082 CPU: 0 [68757.024384] EIP is at ath9k_hw_gen_timer_stop+0x13/0x80 [ath9k_hw] [68757.024384] EAX: d32d0000 EBX: d32d0000 ECX: 00000000 EDX: 00000000 [68757.024384] ESI: e67c24c0 EDI: 00000296 EBP: e137be2c ESP: e137be20 [68757.024384] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 [68757.024384] CR0: 8005003b CR2: 0000000c CR3: 00b99000 CR4: 000407d0 [68757.024384] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [68757.024384] DR6: ffff0ff0 DR7: 00000400 [68757.024384] Process kworker/u:2 (pid: 8917, ti=e137a000 task=ea7a6860 task.ti=e137a000) [68757.024384] Stack: [68757.024384] c06c4676 d32d0000 e67c24c0 e137be38 f81c9590 e67c1ca0 e137be40 f81c95d9 [68757.024384] e137be64 f81cd1c5 00000246 00000002 d32d0000 e67c05e0 e67c1ca0 e67c05e0 [68757.024384] 00000000 e137beac f81cdfa0 e137be84 00000246 00000246 e67c1ca0 e67c1ca0 [68757.024384] Call Trace: [68757.024384] [] ? _raw_spin_lock_irqsave+0x86/0xa0 [68757.024384] [] ath9k_gen_timer_stop+0x10/0x40 [ath9k] [68757.024384] [] ath9k_btcoex_stop_gen_timer+0x19/0x20 [ath9k] [68757.024384] [] ath9k_ps_restore+0x85/0x110 [ath9k] [68757.024384] [] ath9k_config+0x220/0x520 [ath9k] [68757.024384] [] ? ath9k_flush+0x15d/0x1b0 [ath9k] [68757.024384] [] ieee80211_hw_config+0x135/0x2c0 [mac80211] [68757.024384] [] ieee80211_dynamic_ps_enable_work+0x198/0x5f0 [mac80211] Cc: Rajkumar Manoharan Cc: Bala Shanmugam Signed-off-by: Mohammed Shafi Shajakhan Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/gpio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath9k/gpio.c b/drivers/net/wireless/ath/ath9k/gpio.c index bacdb8f..9f83f71 100644 --- a/drivers/net/wireless/ath/ath9k/gpio.c +++ b/drivers/net/wireless/ath/ath9k/gpio.c @@ -341,7 +341,8 @@ void ath9k_btcoex_stop_gen_timer(struct ath_softc *sc) { struct ath_btcoex *btcoex = &sc->btcoex; - ath9k_gen_timer_stop(sc->sc_ah, btcoex->no_stomp_timer); + if (btcoex->hw_timer_enabled) + ath9k_gen_timer_stop(sc->sc_ah, btcoex->no_stomp_timer); } u16 ath9k_btcoex_aggr_limit(struct ath_softc *sc, u32 max_4ms_framelen) -- cgit v1.1