usb/105361: [panic] Kernel panic during unmounting mass storage (Creative mp3 player)

[Rahul Siddharthan]

The following reply was made to PR usb/105361; it has been noted by GNATS.

From: "Rahul Siddharthan" <rsidd at online.fr>
To: bug-followup at freebsd.org, linimon at freebsd.org
Cc:  
Subject: Re: usb/105361: [panic] Kernel panic during unmounting mass storage (Creative mp3 player)
Date: Fri, 24 Aug 2007 15:11:36 +0530

 linimon wrote:
 > Does this panic occur if you umnount the device before removal? (We are
 > aware of the problem if a device is removed before unmounting).
 
 I am experimenting with FreeBSD (7.0-CURRENT) after a few years.  My
 USB stick was not initialised by the system: it was recognised but no
 device node was created.  When I inserted and removed it a few times,
 the system panicked.  (As I said, there was no device node, so no mounting.)
 
 I can submit a backtrace for this if anyone is interested.
 
 I followed the suggested change to usb_subr.c here:
    http://lists.freebsd.org/pipermail/freebsd-questions/2006-February/112698.html
 and, after this, the system creates a da0 device, and
    mount -t msdosfs /dev/da0s1 /mnt
 works.  I haven't yet got a panic by unmounting and removing, but removing
 without unmounting does cause a panic still (as you say you are aware).
 
 Other than this issue FreeBSD-7 seems remarkably stable so far.   But this
 problem with removable media has been around since floppy disk days, and
 really seems to preclude using FreeBSD on any desktop machine where
 uptime is important (eg, a compute workstation where long-term jobs
 are running).