Hi Qianfan,
do you have a serial console connected where the dmesg is sent to?
Be aware that in such a case, at 115kBaud, 1 ms is needed to
print 10 characters.
When i look at the timestamps between two lines of the stack dump,
i can see that ~10ms are needed to print one line which means 100 chars.
Thats reasonable.
I hit that pitfall in the past multiple times ....
Best regards
Carsten
-----Original Message-----
From: qianfan <qianfanguijin@xxxxxxx>
Sent: Freitag, 18. März 2022 03:08
To: Bin Liu <b-liu@xxxxxx>; Wim Van Sebroeck <wim@xxxxxxxxxxxxxxxxxx>; Guenter Roeck <linux@xxxxxxxxxxxx>
Cc: linux-usb@xxxxxxxxxxxxxxx; linux-watchdog@xxxxxxxxxxxxxxx
Subject: Re: dev_WARN_ONCE cause gpio-watchdog reset
在 2022/3/18 8:44, qianfan 写道:
> Hi:
>
> I have a custom AM3352 board with linux v5.15 support. I had enabled
> gpio-watchdog driver and the timeout of gpio-watchdog is 1.6s .
>
> The system will reboot when AM3352's MUSB driver print warn message:
> (next is the log)
>
> [ 1555.665496] ------------[ cut here ]------------
> [ 1555.670343] WARNING: CPU: 0 PID: 345 at
> drivers/usb/musb/musb_host.c:115 musb_h_tx_flush_fifo+0x11c/0x13c
> [ 1555.680395] musb-hdrc musb-hdrc.0: Could not flush host TX10 fifo:
> csr: 2403
> [ 1555.687779] Modules linked in:
> [ 1555.690989] CPU: 0 PID: 345 Comm: kworker/0:1 Not tainted
> 5.15.0-00013-g0ccd7df8f5ad #122
> [ 1555.699560] Hardware name: Generic AM33XX (Flattened Device Tree)
> [ 1555.705946] Workqueue: usb_hub_wq hub_event
> [ 1555.710359] [<c0111438>] (unwind_backtrace) from [<c010b9f4>]
> (show_stack+0x10/0x14)
> [ 1555.718497] [<c010b9f4>] (show_stack) from [<c0adc24c>]
> (dump_stack_lvl+0x40/0x4c)
> [ 1555.726453] [<c0adc24c>] (dump_stack_lvl) from [<c0136264>]
> (__warn+0xf0/0x104)
> [ 1555.734126] [<c0136264>] (__warn) from [<c01362ec>]
> (warn_slowpath_fmt+0x74/0xbc)
> [ 1555.741973] [<c01362ec>] (warn_slowpath_fmt) from [<c07e8b40>]
> (musb_h_tx_flush_fifo+0x11c/0x13c)
> [ 1555.751280] [<c07e8b40>] (musb_h_tx_flush_fifo) from [<c07ea024>]
> (musb_cleanup_urb+0x128/0x204)
> [ 1555.760495] [<c07ea024>] (musb_cleanup_urb) from [<c07ea1e4>]
> (musb_urb_dequeue+0xe4/0x17c)
> [ 1555.769253] [<c07ea1e4>] (musb_urb_dequeue) from [<c07c33f4>]
> (usb_hcd_flush_endpoint+0x118/0x130)
> [ 1555.778654] [<c07c33f4>] (usb_hcd_flush_endpoint) from [<c07c66ec>]
> (usb_disable_endpoint+0x58/0xa4)
> [ 1555.788232] [<c07c66ec>] (usb_disable_endpoint) from [<c07c6828>]
> (usb_disable_interface+0x3c/0x54)
> [ 1555.797716] [<c07c6828>] (usb_disable_interface) from [<c07c8f3c>]
> (usb_unbind_interface+0x160/0x224)
> [ 1555.807385] [<c07c8f3c>] (usb_unbind_interface) from [<c06a731c>]
> (device_release_driver_internal+0x1d0/0x1d8)
> [ 1555.817882] [<c06a731c>] (device_release_driver_internal) from
> [<c07b062c>] (usbnet_cdc_unbind+0x70/0x78)
> [ 1555.827926] [<c07b062c>] (usbnet_cdc_unbind) from [<c07b2098>]
> (usbnet_disconnect+0x48/0xd8)
> [ 1555.836780] [<c07b2098>] (usbnet_disconnect) from [<c07c8e40>]
> (usb_unbind_interface+0x64/0x224)
> [ 1555.845993] [<c07c8e40>] (usb_unbind_interface) from [<c06a731c>]
> (device_release_driver_internal+0x1d0/0x1d8)
> [ 1555.856480] [<c06a731c>] (device_release_driver_internal) from
> [<c06a5bf4>] (bus_remove_device+0xc8/0xf8)
> [ 1555.866515] [<c06a5bf4>] (bus_remove_device) from [<c06a0e5c>]
> (device_del+0x180/0x404)
> [ 1555.874909] [<c06a0e5c>] (device_del) from [<c07c68c8>]
> (usb_disable_device+0x88/0x130)
> [ 1555.883300] [<c07c68c8>] (usb_disable_device) from [<c07bd410>]
> (usb_disconnect+0xb0/0x234)
> [ 1555.892057] [<c07bd410>] (usb_disconnect) from [<c07bf968>]
> (hub_event+0xf3c/0x1288)
> [ 1555.900179] [<c07bf968>] (hub_event) from [<c015306c>]
> (process_one_work+0x22c/0x55c)
> [ 1555.908401] [<c015306c>] (process_one_work) from [<c01533c8>]
> (worker_thread+0x2c/0x5cc)
> [ 1555.916889] [<c01533c8>] (worker_thread) from [<c015b028>]
> (kthread+0x140/0x168)
> [ 1555.924652] [<c015b028>] (kthread) from [<c0100150>]
> (ret_from_fork+0x14/0x24)
> [ 1555.932226] Exception stack(0▒
> U-Boot SPL 2022.01-rc1-00183-gfa5b4e2d19 (Feb 24 2022 - 15:48:38 +0800)
> Trying to boot from NAND
>
> Could you please give me some advice?
>
> Thanks
>
Adding a printk message on gpio_wdt_ping and redroduce this question:
diff --git a/drivers/watchdog/gpio_wdt.c b/drivers/watchdog/gpio_wdt.c
index 4102328a522f..fcfd07e0445a 100644
--- a/drivers/watchdog/gpio_wdt.c
+++ b/drivers/watchdog/gpio_wdt.c
@@ -57,6 +57,7 @@ static int gpio_wdt_ping(struct watchdog_device *wdd)
case HW_ALGO_TOGGLE:
/* Toggle output pin */
priv->state = !priv->state;
+ printk("gwp\n");
gpiod_set_value_cansleep(priv->gpiod, priv->state);
break;
case HW_ALGO_LEVEL:
Next is the log:
[ 90.222821] gwp
[ 91.024956] gwp
[ 91.826936] gwp
[ 92.628898] gwp
[ 93.430888] gwp
[ 94.232859] gwp
[ 94.264325] musb-hdrc musb-hdrc.0: ep11 RX three-strikes error
[ 95.034845] gwp
[ 95.836791] gwp
[ 96.164582] gwp
[ 96.269984] usb 1-1: USB disconnect, device number 3
[ 96.275556] rndis_host 1-1:1.0 usb0: unregister 'rndis_host'
usb-musb-hdrc.0-1, RNDIS device
[ 97.279609] ------------[ cut here ]------------
[ 97.284455] WARNING: CPU: 0 PID: 67 at
drivers/usb/musb/musb_host.c:115 musb_h_tx_flush_fifo+0x11c/0x13c
[ 97.294417] musb-hdrc musb-hdrc.0: Could not flush host TX10 fifo:
csr: 2403
[ 97.301801] Modules linked in:
[ 97.305012] CPU: 0 PID: 67 Comm: kworker/0:12 Not tainted
5.15.0-00013-g0ccd7df8f5ad-dirty #123
[ 97.314130] Hardware name: Generic AM33XX (Flattened Device Tree)
[ 97.320515] Workqueue: usb_hub_wq hub_event
[ 97.324928] [<c0111438>] (unwind_backtrace) from [<c010b9f4>]
(show_stack+0x10/0x14)
[ 97.333066] [<c010b9f4>] (show_stack) from [<c0adc25c>]
(dump_stack_lvl+0x40/0x4c)
[ 97.341023] [<c0adc25c>] (dump_stack_lvl) from [<c0136264>]
(__warn+0xf0/0x104)
[ 97.348697] [<c0136264>] (__warn) from [<c01362ec>]
(warn_slowpath_fmt+0x74/0xbc)
[ 97.356545] [<c01362ec>] (warn_slowpath_fmt) from [<c07e8b40>]
(musb_h_tx_flush_fifo+0x11c/0x13c)
[ 97.365854] [<c07e8b40>] (musb_h_tx_flush_fifo) from [<c07ea024>]
(musb_cleanup_urb+0x128/0x204)
[ 97.375069] [<c07ea024>] (musb_cleanup_urb) from [<c07ea1e4>]
(musb_urb_dequeue+0xe4/0x17c)
[ 97.383829] [<c07ea1e4>] (musb_urb_dequeue) from [<c07c33f4>]
(usb_hcd_flush_endpoint+0x118/0x130)
[ 97.393230] [<c07c33f4>] (usb_hcd_flush_endpoint) from [<c07c66ec>]
(usb_disable_endpoint+0x58/0xa4)
[ 97.402810] [<c07c66ec>] (usb_disable_endpoint) from [<c07c6828>]
(usb_disable_interface+0x3c/0x54)
[ 97.412294] [<c07c6828>] (usb_disable_interface) from [<c07c8f3c>]
(usb_unbind_interface+0x160/0x224)
[ 97.421963] [<c07c8f3c>] (usb_unbind_interface) from [<c06a731c>]
(device_release_driver_internal+0x1d0/0x1d8)
[ 97.432461] [<c06a731c>] (device_release_driver_internal) from
[<c07b062c>] (usbnet_cdc_unbind+0x70/0x78)
[ 97.442505] [<c07b062c>] (usbnet_cdc_unbind) from [<c07b2098>]
(usbnet_disconnect+0x48/0xd8)
[ 97.451359] [<c07b2098>] (usbnet_disconnect) from [<c07c8e40>]
(usb_unbind_interface+0x64/0x224)
[ 97.460573] [<c07c8e40>] (usb_unbind_interface) from [<c06a731c>]
(device_release_driver_internal+0x1d0/0x1d8)
[ 97.471061] [<c06a731c>] (device_release_driver_internal) from
[<c06a5bf4>] (bus_remove_device+0xc8/0xf8)
[ 97.481097] [<c06a5bf4>] (bus_remove_device) from [<c06a0e5c>]
(device_del+0x180/0x404)
[ 97.489491] [<c06a0e5c>] (device_del) from [<c07c68c8>]
(usb_disable_device+0x88/0x130)
[ 97.497882] [<c07c68c8>] (usb_disable_device) from [<c07bd410>]
(usb_disconnect+0xb0/0x234)
[ 97.506640] [<c07bd410>] (usb_disconnect) from [<c07bf968>]
(hub_event+0xf3c/0x1288)
[ 97.514762] [<c07bf968>] (hub_event) from [<c015306c>]
(process_one_work+0x22c/0x55c)
[ 97.522986] [<c015306c>] (process_one_work) from [<c01533c8>]
(worker_thread+0x2c/0x5cc)
[ 97.531473] [<c01533c8>] (worker_thread) from [<c015b028>]
(kthread+0x140/0x168)
[ 97.539237] [<c015b028>] (kthread) from [<c0100150>]
(ret_from_fork+0x14/0x24)
[ 97.546812] Exception stack(0xc3157fb0 to 0xc3157ff8)
[ 97.552106] 7fa0: 00000000
00000000 00000000 00000000
[ 97.560674] 7fc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[ 97.569241] 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[ 97.576170] ---[ end trace 96798796855f16a3 ]---
[ 97.582427] gwp
[ 98.384391] gwp
[ 99.186369] gwp
[ 99.988316] gwp
The last time before dev_WARN_ONCE is [ 96.164582] and the next time
is [ 97.582427]. It took about 1.4 seconds.
But It should be 0.8s. Here is my dts configurations about gpio-watchdog:
watchdog: watchdog {
compatible = "linux,wdt-gpio";
pinctrl-names = "default";
pinctrl-0 = <&gpiowdt_pins>;
gpios = <&gpio3 8 GPIO_ACTIVE_HIGH>;
enable-gpios = <&gpio3 7 GPIO_ACTIVE_LOW>;
always-running;
hw_algo = "toggle";
hw_margin_ms = <1600>;
};
The watchdog ping work is trigger by kthread_queue_work, is it means
dev_WARN_ONCE delayed kthread_queue_work?
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