usb/122287: Removal of usb serial Device with session (eg tip) attached panics system

[Vince Hoffman]

>Number:         122287
>Category:       usb
>Synopsis:       Removal of usb serial Device with session (eg tip) attached panics system
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-usb
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Mar 31 10:00:06 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator:     Vince Hoffman
>Release:        FreeBSD 7.0-STABLE  #52
>Organization:
none
>Environment:
System: FreeBSD prawn.unsane.co.uk 7.0-STABLE FreeBSD 7.0-STABLE #52: Tue Mar 25 13:45:50 GMT 2008     toor at prawn.unsane.co.uk:/usr/local/obj/usr/src/sys/PRAWN7ULE  i386


>Description:
	removing a USB device that has an open session (for example tip) will 
panic the kernel, this is 100% reproducable for me.
{root at prawn}#more info.14
Dump header from device /dev/ad0s3b
  Architecture: i386
  Architecture Version: 2
  Dump Length: 154411008B (147 MB)
  Blocksize: 512
  Dumptime: Mon Mar 31 09:25:54 2008
  Hostname: prawn.unsane.co.uk
  Magic: FreeBSD Kernel Dump
  Version String: FreeBSD 7.0-STABLE #52: Tue Mar 25 13:45:50 GMT 2008
    toor at prawn.unsane.co.uk:/usr/local/obj/usr/src/sys/PRAWN7ULE
  Panic String: page fault
  Dump Parity: 1302845723
  Bounds: 14
  Dump Status: good

I'm happy to build a kernel with debug symbols if needed but it should be easy
to reproduce.

I have only tried this with a UFTDI device. I have a uark device at home I can
try it with if needed.

>How-To-Repeat:
	With the following entry in /etc/remote
usb0:dv=/dev/ttyU0:br#9600:pa=none:
tip usb0
then unplug the usb serial adapter.
>Fix:

unknown as yet


>Release-Note:
>Audit-Trail:
>Unformatted: