Re: [PATCH v2] usb: hub: fix detection of high tier USB3 devices behind suspended hubs

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 6/25/25 5:11 PM, Mathias Nyman wrote:
> On 24.6.2025 19.40, Konrad Dybcio wrote:
>> On 6/24/25 11:47 AM, Mathias Nyman wrote:
>>> On 23.6.2025 23.31, Konrad Dybcio wrote:
>>>> On 6/11/25 1:24 PM, Mathias Nyman wrote:

[...]

> I added some memory debugging but wasn't able to trigger this.
> 
> Does this oneliner help? It's a shot in the dark.
> 
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index d41a6c239953..1cc853c428fc 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -1418,6 +1418,7 @@ static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
>  
>     /* Stop hub_wq and related activity */
>     timer_delete_sync(&hub->irq_urb_retry);
> +    flush_delayed_work(&hub->init_work);
>     usb_kill_urb(hub->urb);
>     if (hub->has_indicators)
>         cancel_delayed_work_sync(&hub->leds);

I can't seem to trigger the bug anymore with this (and Alan's change)!

> If not, then could you add 'initcall_debug' to kernel cmd line, and usb core
> dynamic debug before suspend test
> 
> mount -t debugfs none /sys/kernel/debug
> echo 'module usbcore =p' >/sys/kernel/debug/dynamic_debug/control
> 
> Also curious about lsusb -t output

Just hubs:

[root@sc8280xp-crd ~]# lsusb -t
/:  Bus 001.Port 001: Dev 001, Class=root_hub, Driver=xhci-hcd/1p, 480M
/:  Bus 002.Port 001: Dev 001, Class=root_hub, Driver=xhci-hcd/1p, 10000M
/:  Bus 003.Port 001: Dev 001, Class=root_hub, Driver=xhci-hcd/1p, 480M
/:  Bus 004.Port 001: Dev 001, Class=root_hub, Driver=xhci-hcd/1p, 10000M

Konrad