Re: NETDEV WATCHDOG: eth0 (atl1c): transmit queue 0 timed out
From: Thomas Meyer <hidden>
Date: 2012-02-25 09:52:57
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Am Freitag, den 24.02.2012, 20:20 +0100 schrieb Eric Dumazet:
Le mardi 21 février 2012 à 19:14 +0100, Eric Dumazet a écrit :quoted
Le mardi 21 février 2012 à 18:56 +0100, Thomas Meyer a écrit :quoted
Bad news. Just did hit the issue again, with above patch applied. abrt_version: 2.0.7 cmdline: BOOT_IMAGE=/vmlinuz-3.2.6 root=/dev/sda2 rootfstype=ext4 rootflags=data=writeback ro quiet rhgb kernel: 3.2.6 reason: [177799.342250] WARNING: at net/sched/sch_generic.c:255 dev_watchdog+0x1e7/0x1f0() time: Di 21 Feb 2012 18:09:16 CET backtrace: :[177799.342250] WARNING: at net/sched/sch_generic.c:255 dev_watchdog+0x1e7/0x1f0() :[177799.342254] Hardware name: Aspire 1810T :[177799.342256] NETDEV WATCHDOG: eth0 (atl1c): transmit queue 0 timed out :[177799.342259] Modules linked in: vfat fat fuse bluetooth nf_conntrack_ipv6 nf_defrag_ipv6 ip6t_REJECT ip6table_filter ip6_tables snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq arc4 snd_seq_device snd_pcm iwlwifi uvcvideo mac80211 snd_timer videodev cfg80211 snd usb_storage v4l2_compat_ioctl32 atl1c acer_wmi soundcore sparse_keymap snd_page_alloc rfkill wmi joydev acerhdf pcspkr virtio_net virtio virtio_ring kvm_intel kvm uinput ipv6 [last unloaded: scsi_wait_scan] :[177799.342303] Pid: 4980, comm: alsa-sink Not tainted 3.2.6 #7 :[177799.342306] Call Trace: :[177799.342309] <IRQ> [<ffffffff810322ca>] warn_slowpath_common+0x7a/0xb0 :[177799.342320] [<ffffffff810323a1>] warn_slowpath_fmt+0x41/0x50 :[177799.342325] [<ffffffff8100375b>] ? do_IRQ+0x5b/0xd0 :[177799.342330] [<ffffffff813e94b7>] dev_watchdog+0x1e7/0x1f0 :[177799.342336] [<ffffffff8103cfcf>] run_timer_softirq+0xef/0x210 :[177799.342341] [<ffffffff813e92d0>] ? qdisc_reset+0x50/0x50 :[177799.342345] [<ffffffff81037827>] __do_softirq+0x87/0x110 :[177799.342350] [<ffffffff8149483a>] call_softirq+0x1a/0x30 :[177799.342354] [<ffffffff810038bd>] do_softirq+0x4d/0x80 :[177799.342358] [<ffffffff81037a8e>] irq_exit+0x7e/0xa0 :[177799.342363] [<ffffffff8101903a>] smp_apic_timer_interrupt+0x5a/0x90 :[177799.342368] [<ffffffff814942a9>] apic_timer_interrupt+0x69/0x70 :[177799.342371] <EOI> [<ffffffff814948d7>] ? sysenter_dispatch+0x7/0x26 END:Thanks This driver xmit function is racy I suspect, and several patches will be needed to fix bugs.Here is a cumulative patch to hopefuly remove the races in this driver, could you please test it ?
Hi, just building a 3.2.7 kernel with your patch applied. I will watch out for the warning in the next days. many thanks for the patch! kind regards thomas
quoted hunk ↗ jump to hunk
diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c.h b/drivers/net/ethernet/atheros/atl1c/atl1c.h index ca70e16..3b2851b 100644 --- a/drivers/net/ethernet/atheros/atl1c/atl1c.h +++ b/drivers/net/ethernet/atheros/atl1c/atl1c.h@@ -576,7 +576,6 @@ struct atl1c_adapter { u16 link_duplex; spinlock_t mdio_lock; - spinlock_t tx_lock; atomic_t irq_sem; struct work_struct common_task;diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c index 1ff3c6d..896eb20 100644 --- a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c +++ b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c@@ -784,7 +784,6 @@ static int __devinit atl1c_sw_init(struct atl1c_adapter *adapter) atl1c_set_rxbufsize(adapter, adapter->netdev); atomic_set(&adapter->irq_sem, 1); spin_lock_init(&adapter->mdio_lock); - spin_lock_init(&adapter->tx_lock); set_bit(__AT_DOWN, &adapter->flags); return 0;@@ -1653,9 +1652,11 @@ static bool atl1c_clean_tx_irq(struct atl1c_adapter *adapter, atomic_set(&tpd_ring->next_to_clean, next_to_clean); } - if (netif_queue_stopped(adapter->netdev) && - netif_carrier_ok(adapter->netdev)) { - netif_wake_queue(adapter->netdev); + if (netif_carrier_ok(adapter->netdev)) { + /* make sure atl1c_xmit_frame() see our changes */ + smp_mb(); + if (netif_queue_stopped(adapter->netdev)) + netif_wake_queue(adapter->netdev); } return true;@@ -2228,7 +2229,6 @@ static netdev_tx_t atl1c_xmit_frame(struct sk_buff *skb, struct net_device *netdev) { struct atl1c_adapter *adapter = netdev_priv(netdev); - unsigned long flags; u16 tpd_req = 1; struct atl1c_tpd_desc *tpd; enum atl1c_trans_queue type = atl1c_trans_normal;@@ -2239,24 +2239,20 @@ static netdev_tx_t atl1c_xmit_frame(struct sk_buff *skb, } tpd_req = atl1c_cal_tpd_req(skb); - if (!spin_trylock_irqsave(&adapter->tx_lock, flags)) { - if (netif_msg_pktdata(adapter)) - dev_info(&adapter->pdev->dev, "tx locked\n"); - return NETDEV_TX_LOCKED; - } if (atl1c_tpd_avail(adapter, type) < tpd_req) { /* no enough descriptor, just stop queue */ netif_stop_queue(netdev); - spin_unlock_irqrestore(&adapter->tx_lock, flags); - return NETDEV_TX_BUSY; + smp_mb(); + if (atl1c_tpd_avail(adapter, type) < tpd_req) + return NETDEV_TX_BUSY; + netif_wake_queue(netdev); } tpd = atl1c_get_tpd(adapter, type); /* do TSO and check sum */ if (atl1c_tso_csum(adapter, skb, &tpd, type) != 0) { - spin_unlock_irqrestore(&adapter->tx_lock, flags); dev_kfree_skb_any(skb); return NETDEV_TX_OK; }@@ -2277,7 +2273,6 @@ static netdev_tx_t atl1c_xmit_frame(struct sk_buff *skb, atl1c_tx_map(adapter, skb, tpd, type); atl1c_tx_queue(adapter, skb, tpd, type); - spin_unlock_irqrestore(&adapter->tx_lock, flags); return NETDEV_TX_OK; }