From e55b32c110b025ce07b40227f620e99700bf8741 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Mon, 28 Nov 2011 10:33:40 +0100 Subject: [PATCH] rtlwifi: fix lps_lock deadlock rtl_lps_leave can be called from interrupt context, so we have to disable interrupts when taking lps_lock. Below is full lockdep info about deadlock: [ 93.815269] ================================= [ 93.815390] [ INFO: inconsistent lock state ] [ 93.815472] 2.6.41.1-3.offch.fc15.x86_64.debug #1 [ 93.815556] --------------------------------- [ 93.815635] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 93.815743] swapper/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 93.815832] (&(&rtlpriv->locks.lps_lock)->rlock){+.?...}, at: [] rtl_lps_leave+0x26/0x103 [rtlwifi] [ 93.815947] {SOFTIRQ-ON-W} state was registered at: [ 93.815947] [] __lock_acquire+0x369/0xd0c [ 93.815947] [] lock_acquire+0xf3/0x13e [ 93.815947] [] _raw_spin_lock+0x45/0x79 [ 93.815947] [] rtl_swlps_rf_awake+0x5a/0x76 [rtlwifi] [ 93.815947] [] rtl_op_config+0x12a/0x32a [rtlwifi] [ 93.815947] [] ieee80211_hw_config+0x124/0x129 [mac80211] [ 93.815947] [] ieee80211_dynamic_ps_disable_work+0x32/0x47 [mac80211] [ 93.815947] [] process_one_work+0x205/0x3e7 [ 93.815947] [] worker_thread+0xda/0x15d [ 93.815947] [] kthread+0xa8/0xb0 [ 93.815947] [] kernel_thread_helper+0x4/0x10 [ 93.815947] irq event stamp: 547822 [ 93.815947] hardirqs last enabled at (547822): [] _raw_spin_unlock_irqrestore+0x45/0x61 [ 93.815947] hardirqs last disabled at (547821): [] _raw_spin_lock_irqsave+0x22/0x8e [ 93.815947] softirqs last enabled at (547790): [] _local_bh_enable+0x13/0x15 [ 93.815947] softirqs last disabled at (547791): [] call_softirq+0x1c/0x30 [ 93.815947] [ 93.815947] other info that might help us debug this: [ 93.815947] Possible unsafe locking scenario: [ 93.815947] [ 93.815947] CPU0 [ 93.815947] ---- [ 93.815947] lock(&(&rtlpriv->locks.lps_lock)->rlock); [ 93.815947] [ 93.815947] lock(&(&rtlpriv->locks.lps_lock)->rlock); [ 93.815947] [ 93.815947] *** DEADLOCK *** [ 93.815947] [ 93.815947] no locks held by swapper/0. [ 93.815947] [ 93.815947] stack backtrace: [ 93.815947] Pid: 0, comm: swapper Not tainted 2.6.41.1-3.offch.fc15.x86_64.debug #1 [ 93.815947] Call Trace: [ 93.815947] [] print_usage_bug+0x1e7/0x1f8 [ 93.815947] [] ? save_stack_trace+0x2c/0x49 [ 93.815947] [] ? print_irq_inversion_bug.part.18+0x1a0/0x1a0 [ 93.815947] [] mark_lock+0x106/0x220 [ 93.815947] [] __lock_acquire+0x2f5/0xd0c [ 93.815947] [] ? native_sched_clock+0x34/0x36 [ 93.830125] [] ? sched_clock+0x9/0xd [ 93.830125] [] ? sched_clock_local+0x12/0x75 [ 93.830125] [] ? rtl_lps_leave+0x26/0x103 [rtlwifi] [ 93.830125] [] lock_acquire+0xf3/0x13e [ 93.830125] [] ? rtl_lps_leave+0x26/0x103 [rtlwifi] [ 93.830125] [] _raw_spin_lock+0x45/0x79 [ 93.830125] [] ? rtl_lps_leave+0x26/0x103 [rtlwifi] [ 93.830125] [] ? skb_dequeue+0x62/0x6d [ 93.830125] [] rtl_lps_leave+0x26/0x103 [rtlwifi] [ 93.830125] [] _rtl_pci_ips_leave_tasklet+0xe/0x10 [rtlwifi] [ 93.830125] [] tasklet_action+0x8d/0xee [ 93.830125] [] __do_softirq+0x112/0x25a [ 93.830125] [] call_softirq+0x1c/0x30 [ 93.830125] [] do_softirq+0x4b/0xa1 [ 93.830125] [] irq_exit+0x5d/0xcf [ 93.830125] [] do_IRQ+0x8e/0xa5 [ 93.830125] [] common_interrupt+0x73/0x73 [ 93.830125] [] ? trace_hardirqs_off+0xd/0xf [ 93.830125] [] ? intel_idle+0xe5/0x10c [ 93.830125] [] ? intel_idle+0xe1/0x10c [ 93.830125] [] cpuidle_idle_call+0x11c/0x1fe [ 93.830125] [] cpu_idle+0xab/0x101 [ 93.830125] [] rest_init+0xd7/0xde [ 93.830125] [] ? csum_partial_copy_generic+0x16c/0x16c [ 93.830125] [] start_kernel+0x3dd/0x3ea [ 93.830125] [] x86_64_start_reservations+0xaf/0xb3 [ 93.830125] [] ? early_idt_handlers+0x140/0x140 [ 93.830125] [] x86_64_start_kernel+0x102/0x111 Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=755154 Reported-by: vjain02@students.poly.edu Reported-and-tested-by: Oliver Paukstadt Cc: stable@vger.kernel.org Acked-by: Larry Finger Signed-off-by: Stanislaw Gruszka Signed-off-by: John W. Linville --- drivers/net/wireless/rtlwifi/ps.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/net/wireless/rtlwifi/ps.c b/drivers/net/wireless/rtlwifi/ps.c index a693feffbe..0b04b2e 100644 --- a/drivers/net/wireless/rtlwifi/ps.c +++ b/drivers/net/wireless/rtlwifi/ps.c @@ -394,7 +394,7 @@ void rtl_lps_enter(struct ieee80211_hw *hw) if (mac->link_state != MAC80211_LINKED) return; - spin_lock(&rtlpriv->locks.lps_lock); + spin_lock_irq(&rtlpriv->locks.lps_lock); /* Idle for a while if we connect to AP a while ago. */ if (mac->cnt_after_linked >= 2) { @@ -406,7 +406,7 @@ void rtl_lps_enter(struct ieee80211_hw *hw) } } - spin_unlock(&rtlpriv->locks.lps_lock); + spin_unlock_irq(&rtlpriv->locks.lps_lock); } /*Leave the leisure power save mode.*/ @@ -415,8 +415,9 @@ void rtl_lps_leave(struct ieee80211_hw *hw) struct rtl_priv *rtlpriv = rtl_priv(hw); struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw)); struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw)); + unsigned long flags; - spin_lock(&rtlpriv->locks.lps_lock); + spin_lock_irqsave(&rtlpriv->locks.lps_lock, flags); if (ppsc->fwctrl_lps) { if (ppsc->dot11_psmode != EACTIVE) { @@ -437,7 +438,7 @@ void rtl_lps_leave(struct ieee80211_hw *hw) rtl_lps_set_psmode(hw, EACTIVE); } } - spin_unlock(&rtlpriv->locks.lps_lock); + spin_unlock_irqrestore(&rtlpriv->locks.lps_lock, flags); } /* For sw LPS*/ @@ -538,9 +539,9 @@ void rtl_swlps_rf_awake(struct ieee80211_hw *hw) RT_CLEAR_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM); } - spin_lock(&rtlpriv->locks.lps_lock); + spin_lock_irq(&rtlpriv->locks.lps_lock); rtl_ps_set_rf_state(hw, ERFON, RF_CHANGE_BY_PS); - spin_unlock(&rtlpriv->locks.lps_lock); + spin_unlock_irq(&rtlpriv->locks.lps_lock); } void rtl_swlps_rfon_wq_callback(void *data) @@ -573,9 +574,9 @@ void rtl_swlps_rf_sleep(struct ieee80211_hw *hw) if (rtlpriv->link_info.busytraffic) return; - spin_lock(&rtlpriv->locks.lps_lock); + spin_lock_irq(&rtlpriv->locks.lps_lock); rtl_ps_set_rf_state(hw, ERFSLEEP, RF_CHANGE_BY_PS); - spin_unlock(&rtlpriv->locks.lps_lock); + spin_unlock_irq(&rtlpriv->locks.lps_lock); if (ppsc->reg_rfps_level & RT_RF_OFF_LEVL_ASPM && !RT_IN_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM)) { -- 2.7.4