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Re: Reboot resistant USB bug



On 16/10/18 16:00, Christos Zoulas wrote:
In article <20181016122719.GI16483%homeworld.netbsd.org@localhost>,
Emmanuel Dreyfus  <manu%netbsd.org@localhost> wrote:
On Thu, Oct 11, 2018 at 02:11:22PM +0000, Emmanuel Dreyfus wrote:
On both netbsd-8 and -current, I have a problem with USB devices that
get stuck in a non-functionning state even after a reboot.

I investigated a lot: in my example, the pn533 chip seems to corrupts
its USB config, interface and endpoint descriptors. They contain
garbage, and on reboot the kernel cannot figure enough  about the
device, and disable the USB port.

But if I detect the condition in usbd_get_desc() and inject
fake descriptors (see below), the device is correctly attached
on reboot, and it works again. Is it an acceptable workaround?
[snip]


Isn't there a way to reset it?

Doesn't the hub power the port down? The bug is probably in uhub.c


christos



Nick


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