Subject: kern/22218: USB isoc locks
To: None <gnats-bugs@gnats.netbsd.org>
From: None <coto@core.de>
List: netbsd-bugs
Date: 07/22/2003 10:04:13
>Number:         22218
>Category:       kern
>Synopsis:       using a USB isochronous endpoint freezes kernel
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Jul 22 08:05:00 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     Thomas Runge
>Release:        NetBSD 1.6U, snapshot from 07/20/03
>Organization:
>Environment:
Architecture: i386
Machine: i386
>Description:
	Using bktr2jpeg (version 2.0a9) with a USB webcam the kernel
freezes hard whenever the app reads from the isochronous endpoint. This
happens on 1.6.1_STABLE too.
>How-To-Repeat:
	Using said application available here:
http://core.de/~coto/projects/bktr2jpeg/ with a supported webcam
(ov511 based) or probably any other application reading from any isoc.
>Fix:
	There once was a suggestion to comment out the last line in
src/sys/dev/usb/ohci.c:ohci_device_isoc_done (remove xfer->hcpriv = NULL;)
as a workaround. This works (on -stable and -current), but seems to just
hide the bug.
>Release-Note:
>Audit-Trail:
>Unformatted: