Re: Kernel panic during boot in usb_add_task

[Michael Neumann <mneumann@xxxxxxxx>]

Michael Neumann wrote:
> Michael Neumann schrieb:
> > Bill Hacker schrieb:
> > > Michael Neumann wrote:
> > > For starters, what does NetBSD report as the hardware and can you 
> > > capture *any* scan, dmesg, or other report from FreeBSD 7-BETA3 or DFLY?

I could track it down where the panic occurs:

http://opengrok.creo.hu/dragonfly/xref/src/sys/bus/usb/usb.c#374

More specifically:

  http://opengrok.creo.hu/dragonfly/xref/src/sys/sys/queue.h#428

  *(head)->tqh_last = (elm);

This expands to:

  *(&taskq->tasks)->tgh_last = task;

There a NULL pointer is dereferenced somehow.

usb_add_task is called from uhci_timeout:

  http://opengrok.creo.hu/dragonfly/xref/src/sys/bus/usb/uhci.c#1428

It seems to get only called when a timeout occurs. That's maybe that I 
am the only one having those problems :)

I couldn't track it down further. My pure guess would be that it would 
not panic if "uhci_abort_xfer(&uxfer->xfer, USBD_TIMEOUT);" is called 
instead (sc->sc_dying == 1), but I can't build a kernel right now, so I 
can't change the code and build an ISO image.

Any further ideas?

Regards,

  Michael