From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933619Ab1LGQWn (ORCPT ); Wed, 7 Dec 2011 11:22:43 -0500 Received: from cantor2.suse.de ([195.135.220.15]:34033 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933596Ab1LGQWi (ORCPT ); Wed, 7 Dec 2011 11:22:38 -0500 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Dec 7 08:12:17 2011 Message-Id: <20111207161217.318885552@clark.kroah.org> User-Agent: quilt/0.50-23.1 Date: Wed, 07 Dec 2011 08:11:33 -0800 From: Greg KH To: , Cc: , , , Larry Finger , Stanislaw Gruszka , "John W. Linville" Subject: [031/104] rtlwifi: fix lps_lock deadlock In-Reply-To: <20111207161246.GA10995@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stanislaw Gruszka commit e55b32c110b025ce07b40227f620e99700bf8741 upstream. 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 Acked-by: Larry Finger Signed-off-by: Stanislaw Gruszka Signed-off-by: John W. Linville Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/rtlwifi/ps.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) --- 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 * 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 * } } - 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 * 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 * 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 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 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)) {