From 39d501d93d25e4c78fdaf9e83ae00f295ab88a97 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Fri, 26 Apr 2019 09:58:41 +0200 Subject: mt76usb: fix tx/rx stop Disabling tasklets on stopping rx/tx is wrong. If blocked tasklet is scheduled and we remove device we will get 100% cpu usage: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 9 root 20 0 0 0 0 R 93.8 0.0 1:47.19 ksoftirqd/0 by infinite loop in tasklet_action_common() and eventuall crash on next mt76usb module load: [ 2068.591964] RIP: 0010:tasklet_action_common.isra.17+0x66/0x100 [ 2068.591966] Code: 41 89 f5 eb 25 f0 48 0f ba 33 00 0f 83 b1 00 00 00 48 8b 7a 20 48 8b 42 18 e8 56 a3 b5 00 f0 80 23 fd 48 89 ea 48 85 ed 74 53 <48> 8b 2a 48 8d 5a 08 f0 48 0f ba 6a 08 01 72 0b 8b 42 10 85 c0 74 [ 2068.591968] RSP: 0018:ffff98758c34be58 EFLAGS: 00010206 [ 2068.591969] RAX: ffff98758e6966d0 RBX: ffff98756e69aef8 RCX: 0000000000000006 [ 2068.591970] RDX: 01060a053d060305 RSI: 0000000000000006 RDI: ffff98758e6966d0 [ 2068.591971] RBP: 01060a053d060305 R08: 0000000000000000 R09: 00000000000203c0 [ 2068.591971] R10: 000003ff65b34f08 R11: 0000000000000001 R12: ffff98758e6966d0 [ 2068.591972] R13: 0000000000000006 R14: 0000000000000040 R15: 0000000000000006 [ 2068.591974] FS: 0000000000000000(0000) GS:ffff98758e680000(0000) knlGS:0000000000000000 [ 2068.591975] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2068.591975] CR2: 00002c5f73a6cc20 CR3: 00000002f920a001 CR4: 00000000003606e0 [ 2068.591977] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 2068.591978] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 2068.591978] Call Trace: [ 2068.591985] __do_softirq+0xe3/0x30a [ 2068.591989] ? sort_range+0x20/0x20 [ 2068.591990] run_ksoftirqd+0x26/0x40 [ 2068.591992] smpboot_thread_fn+0xc5/0x160 [ 2068.591995] kthread+0x112/0x130 [ 2068.591997] ? kthread_create_on_node+0x40/0x40 [ 2068.591998] ret_from_fork+0x35/0x40 [ 2068.591999] Modules linked in: ccm arc4 fuse rfcomm cmac bnep sunrpc snd_hda_codec_hdmi snd_soc_skl snd_soc_core snd_soc_acpi_intel_match snd_hda_codec_realtek snd_soc_acpi snd_hda_codec_generic snd_soc_skl_ipc snd_soc_sst_ipc snd_soc_sst_dsp snd_hda_ext_core iTCO_wdt snd_hda_intel intel_rapl iTCO_vendor_support x86_pkg_temp_thermal intel_powerclamp btusb mei_wdt coretemp btrtl snd_hda_codec btbcm btintel intel_cstate snd_hwdep intel_uncore uvcvideo snd_hda_core videobuf2_vmalloc videobuf2_memops intel_rapl_perf wmi_bmof videobuf2_v4l2 intel_wmi_thunderbolt snd_seq bluetooth joydev videobuf2_common snd_seq_device snd_pcm videodev media i2c_i801 snd_timer idma64 ecdh_generic intel_lpss_pci intel_lpss mei_me mei ucsi_acpi typec_ucsi processor_thermal_device intel_soc_dts_iosf intel_pch_thermal typec thinkpad_acpi wmi snd soundcore rfkill int3403_thermal int340x_thermal_zone int3400_thermal acpi_thermal_rel acpi_pad pcc_cpufreq uas usb_storage crc32c_intel i915 i2c_algo_bit nvme serio_raw [ 2068.592033] drm_kms_helper e1000e nvme_core drm video ipv6 [last unloaded: cfg80211] Fortunate thing is that this not happen frequently, as scheduling tasklet on blocked state is very exceptional, though might happen. Due to different RX/TX tasklet processing fix is different for those. For RX we have to assure rx_tasklet do fail to resubmit buffers by poisoning urb's and kill the tasklet. For TX we need to handle all stop cases properly (suspend, module unload, device removal). Signed-off-by: Stanislaw Gruszka Signed-off-by: Felix Fietkau --- drivers/net/wireless/mediatek/mt76/mac80211.c | 3 +- drivers/net/wireless/mediatek/mt76/mt76.h | 7 +- drivers/net/wireless/mediatek/mt76/mt76x0/usb.c | 10 +-- drivers/net/wireless/mediatek/mt76/mt76x2/usb.c | 8 +-- .../net/wireless/mediatek/mt76/mt76x2/usb_init.c | 1 - .../net/wireless/mediatek/mt76/mt76x2/usb_main.c | 1 + drivers/net/wireless/mediatek/mt76/usb.c | 78 +++++++++++++++------- 7 files changed, 66 insertions(+), 42 deletions(-) (limited to 'drivers/net/wireless') diff --git a/drivers/net/wireless/mediatek/mt76/mac80211.c b/drivers/net/wireless/mediatek/mt76/mac80211.c index 60b86ca00b3d..12c8f16096d9 100644 --- a/drivers/net/wireless/mediatek/mt76/mac80211.c +++ b/drivers/net/wireless/mediatek/mt76/mac80211.c @@ -390,7 +390,7 @@ void mt76_rx(struct mt76_dev *dev, enum mt76_rxq_id q, struct sk_buff *skb) } EXPORT_SYMBOL_GPL(mt76_rx); -static bool mt76_has_tx_pending(struct mt76_dev *dev) +bool mt76_has_tx_pending(struct mt76_dev *dev) { struct mt76_queue *q; int i; @@ -403,6 +403,7 @@ static bool mt76_has_tx_pending(struct mt76_dev *dev) return false; } +EXPORT_SYMBOL_GPL(mt76_has_tx_pending); void mt76_set_channel(struct mt76_dev *dev) { diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h index 75a0d150a224..90d6e9df02a9 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76.h +++ b/drivers/net/wireless/mediatek/mt76/mt76.h @@ -696,6 +696,7 @@ void mt76_release_buffered_frames(struct ieee80211_hw *hw, u16 tids, int nframes, enum ieee80211_frame_release_type reason, bool more_data); +bool mt76_has_tx_pending(struct mt76_dev *dev); void mt76_set_channel(struct mt76_dev *dev); int mt76_get_survey(struct ieee80211_hw *hw, int idx, struct survey_info *survey); @@ -790,10 +791,10 @@ int mt76u_vendor_request(struct mt76_dev *dev, u8 req, void mt76u_single_wr(struct mt76_dev *dev, const u8 req, const u16 offset, const u32 val); int mt76u_init(struct mt76_dev *dev, struct usb_interface *intf); -int mt76u_submit_rx_buffers(struct mt76_dev *dev); int mt76u_alloc_queues(struct mt76_dev *dev); -void mt76u_stop_queues(struct mt76_dev *dev); -void mt76u_stop_stat_wk(struct mt76_dev *dev); +void mt76u_stop_tx(struct mt76_dev *dev); +void mt76u_stop_rx(struct mt76_dev *dev); +int mt76u_resume_rx(struct mt76_dev *dev); void mt76u_queues_deinit(struct mt76_dev *dev); struct sk_buff * diff --git a/drivers/net/wireless/mediatek/mt76/mt76x0/usb.c b/drivers/net/wireless/mediatek/mt76/mt76x0/usb.c index 53ec7dc38b9d..406ebfa74195 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x0/usb.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x0/usb.c @@ -86,7 +86,7 @@ static void mt76x0u_mac_stop(struct mt76x02_dev *dev) clear_bit(MT76_STATE_RUNNING, &dev->mt76.state); cancel_delayed_work_sync(&dev->cal_work); cancel_delayed_work_sync(&dev->mt76.mac_work); - mt76u_stop_stat_wk(&dev->mt76); + mt76u_stop_tx(&dev->mt76); mt76x02u_exit_beacon_config(dev); if (test_bit(MT76_REMOVED, &dev->mt76.state)) @@ -313,7 +313,7 @@ static int __maybe_unused mt76x0_suspend(struct usb_interface *usb_intf, { struct mt76x02_dev *dev = usb_get_intfdata(usb_intf); - mt76u_stop_queues(&dev->mt76); + mt76u_stop_rx(&dev->mt76); clear_bit(MT76_STATE_MCU_RUNNING, &dev->mt76.state); mt76x0_chip_onoff(dev, false, false); @@ -323,16 +323,12 @@ static int __maybe_unused mt76x0_suspend(struct usb_interface *usb_intf, static int __maybe_unused mt76x0_resume(struct usb_interface *usb_intf) { struct mt76x02_dev *dev = usb_get_intfdata(usb_intf); - struct mt76_usb *usb = &dev->mt76.usb; int ret; - ret = mt76u_submit_rx_buffers(&dev->mt76); + ret = mt76u_resume_rx(&dev->mt76); if (ret < 0) goto err; - tasklet_enable(&usb->rx_tasklet); - tasklet_enable(&dev->mt76.tx_tasklet); - ret = mt76x0u_init_hardware(dev); if (ret) goto err; diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2/usb.c b/drivers/net/wireless/mediatek/mt76/mt76x2/usb.c index c55ad617edce..7a994a783510 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2/usb.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x2/usb.c @@ -107,7 +107,7 @@ static int __maybe_unused mt76x2u_suspend(struct usb_interface *intf, { struct mt76x02_dev *dev = usb_get_intfdata(intf); - mt76u_stop_queues(&dev->mt76); + mt76u_stop_rx(&dev->mt76); return 0; } @@ -115,16 +115,12 @@ static int __maybe_unused mt76x2u_suspend(struct usb_interface *intf, static int __maybe_unused mt76x2u_resume(struct usb_interface *intf) { struct mt76x02_dev *dev = usb_get_intfdata(intf); - struct mt76_usb *usb = &dev->mt76.usb; int err; - err = mt76u_submit_rx_buffers(&dev->mt76); + err = mt76u_resume_rx(&dev->mt76); if (err < 0) goto err; - tasklet_enable(&usb->rx_tasklet); - tasklet_enable(&dev->mt76.tx_tasklet); - err = mt76x2u_init_hardware(dev); if (err < 0) goto err; diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2/usb_init.c b/drivers/net/wireless/mediatek/mt76/mt76x2/usb_init.c index 96ee596a69ec..f2c57d5b87f9 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2/usb_init.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x2/usb_init.c @@ -244,7 +244,6 @@ fail: void mt76x2u_stop_hw(struct mt76x02_dev *dev) { - mt76u_stop_stat_wk(&dev->mt76); cancel_delayed_work_sync(&dev->cal_work); cancel_delayed_work_sync(&dev->mt76.mac_work); mt76x2u_mac_stop(dev); diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2/usb_main.c b/drivers/net/wireless/mediatek/mt76/mt76x2/usb_main.c index dcf67f4845be..305977a874a4 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2/usb_main.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x2/usb_main.c @@ -42,6 +42,7 @@ static void mt76x2u_stop(struct ieee80211_hw *hw) mutex_lock(&dev->mt76.mutex); clear_bit(MT76_STATE_RUNNING, &dev->mt76.state); + mt76u_stop_tx(&dev->mt76); mt76x2u_stop_hw(dev); mutex_unlock(&dev->mt76.mutex); } diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c index d2c6718b5933..c299c6591072 100644 --- a/drivers/net/wireless/mediatek/mt76/usb.c +++ b/drivers/net/wireless/mediatek/mt76/usb.c @@ -540,7 +540,7 @@ static void mt76u_rx_tasklet(unsigned long data) rcu_read_unlock(); } -int mt76u_submit_rx_buffers(struct mt76_dev *dev) +static int mt76u_submit_rx_buffers(struct mt76_dev *dev) { struct mt76_queue *q = &dev->q_rx[MT_RXQ_MAIN]; unsigned long flags; @@ -558,7 +558,6 @@ int mt76u_submit_rx_buffers(struct mt76_dev *dev) return err; } -EXPORT_SYMBOL_GPL(mt76u_submit_rx_buffers); static int mt76u_alloc_rx(struct mt76_dev *dev) { @@ -605,14 +604,29 @@ static void mt76u_free_rx(struct mt76_dev *dev) memset(&q->rx_page, 0, sizeof(q->rx_page)); } -static void mt76u_stop_rx(struct mt76_dev *dev) +void mt76u_stop_rx(struct mt76_dev *dev) { struct mt76_queue *q = &dev->q_rx[MT_RXQ_MAIN]; int i; for (i = 0; i < q->ndesc; i++) - usb_kill_urb(q->entry[i].urb); + usb_poison_urb(q->entry[i].urb); + + tasklet_kill(&dev->usb.rx_tasklet); +} +EXPORT_SYMBOL_GPL(mt76u_stop_rx); + +int mt76u_resume_rx(struct mt76_dev *dev) +{ + struct mt76_queue *q = &dev->q_rx[MT_RXQ_MAIN]; + int i; + + for (i = 0; i < q->ndesc; i++) + usb_unpoison_urb(q->entry[i].urb); + + return mt76u_submit_rx_buffers(dev); } +EXPORT_SYMBOL_GPL(mt76u_resume_rx); static void mt76u_tx_tasklet(unsigned long data) { @@ -834,38 +848,54 @@ static void mt76u_free_tx(struct mt76_dev *dev) } } -static void mt76u_stop_tx(struct mt76_dev *dev) +void mt76u_stop_tx(struct mt76_dev *dev) { + struct mt76_queue_entry entry; struct mt76_queue *q; - int i, j; + int i, j, ret; - for (i = 0; i < IEEE80211_NUM_ACS; i++) { - q = dev->q_tx[i].q; - for (j = 0; j < q->ndesc; j++) - usb_kill_urb(q->entry[j].urb); - } -} + ret = wait_event_timeout(dev->tx_wait, !mt76_has_tx_pending(dev), HZ/5); + if (!ret) { + dev_err(dev->dev, "timed out waiting for pending tx\n"); -void mt76u_stop_queues(struct mt76_dev *dev) -{ - tasklet_disable(&dev->usb.rx_tasklet); - tasklet_disable(&dev->tx_tasklet); + for (i = 0; i < IEEE80211_NUM_ACS; i++) { + q = dev->q_tx[i].q; + for (j = 0; j < q->ndesc; j++) + usb_kill_urb(q->entry[j].urb); + } - mt76u_stop_rx(dev); - mt76u_stop_tx(dev); -} -EXPORT_SYMBOL_GPL(mt76u_stop_queues); + tasklet_kill(&dev->tx_tasklet); + + /* On device removal we maight queue skb's, but mt76u_tx_kick() + * will fail to submit urb, cleanup those skb's manually. + */ + for (i = 0; i < IEEE80211_NUM_ACS; i++) { + q = dev->q_tx[i].q; + + /* Assure we are in sync with killed tasklet. */ + spin_lock_bh(&q->lock); + while (q->queued) { + entry = q->entry[q->head]; + q->head = (q->head + 1) % q->ndesc; + q->queued--; + + dev->drv->tx_complete_skb(dev, i, &entry); + } + spin_unlock_bh(&q->lock); + } + } -void mt76u_stop_stat_wk(struct mt76_dev *dev) -{ cancel_delayed_work_sync(&dev->usb.stat_work); clear_bit(MT76_READING_STATS, &dev->state); + + mt76_tx_status_check(dev, NULL, true); } -EXPORT_SYMBOL_GPL(mt76u_stop_stat_wk); +EXPORT_SYMBOL_GPL(mt76u_stop_tx); void mt76u_queues_deinit(struct mt76_dev *dev) { - mt76u_stop_queues(dev); + mt76u_stop_rx(dev); + mt76u_stop_tx(dev); mt76u_free_rx(dev); mt76u_free_tx(dev); -- cgit v1.2.3