Re: Problem hanging Bulk IN, with USB 3.x, perhaps due to wMaxPacketSize = 1024 and wMaxBurst = 6 (OUT) and 2 (IN), tested and reproduceable with i.MX8MP and Raspberry Pi Compute Module 5 (CM5)

["Michał Pecio" <michal.pecio@gmail.com>]

Hi,

On Fri, 8 Aug 2025 23:47:07 +0200, Martin Maurer wrote:
> What can I do/test next?
> 
> Try again on a AMD x64 controller? Perhaps with main/latest of Linux Kernel?

You are describing some fairly complex setups, can you confidently
say that the problem is USB and not elsewhere? For example, you have
tcpdump running on the USB host machine and packets go out through
the USB network interface but nothing comes back?

What driver are you using with this USB device? Any errors/diagnostics
from the driver, or from xhci_hcd (I guess that's your host)?

You tried usbmon and what happened? Is the driver submitting IN URBs?
Are they coming back empty? With error status? Not completing at all?

Trying on a PC with newer kernel makes sense, debugging may be easier
that way and lower risk of:
- chasing bugs in downstream kernels that nobody here can help with
- fixing something that has already been figured out and fixed

Regards,
Michal