Re: kern/42149: wapbl locking panic if watching DVD

[Nicolas Joly <njoly%pasteur.fr@localhost>]

The following reply was made to PR kern/42149; it has been noted by GNATS.

From: Nicolas Joly <njoly%pasteur.fr@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
        netbsd-bugs%netbsd.org@localhost
Subject: Re: kern/42149: wapbl locking panic if watching DVD
Date: Thu, 25 Feb 2010 17:04:23 +0100

 On Sun, Oct 04, 2009 at 04:05:00PM +0000, Matthias Drochner wrote:
 > >Number:         42149
 > >Category:       kern
 > >Synopsis:       wapbl locking panic if watching DVD
 > >Confidential:   no
 > >Severity:       serious
 > >Priority:       high
 > >Responsible:    kern-bug-people
 > >State:          open
 > >Class:          sw-bug
 > >Submitter-Id:   net
 > >Arrival-Date:   Sun Oct 04 16:05:00 +0000 2009
 > >Originator:     Matthias Drochner
 > >Release:        current of end-September
 > >Organization:
 > >Environment:
 > i386, DIAGNOSTIC+DEBUG kernel,
 > root filesystem is ffs+wapbl
 > >Description:
 > If I either finish watching a DVD (using vlc) or invoke a "sync" during 
 > playback, the kernel panics:
 [...]
 > So as this shows the device node is /dev/cd0d --the block device--
 > which is somewhat unintentional but should of course not cause a
 > panic.
 
 Just got hit by the same KASSERT, but with tunefs ...
 
 njoly@lanfeust [~]> tunefs -N /dev/wd0i
 tunefs: tuning /dev/wd0i
 tunefs: current settings of /dev/wd0i
         maximum contiguous block count 4
         maximum blocks per file in a cylinder group 4096
         minimum percentage of free space 5%
         optimization preference: time
         average file size: 16384
         expected number of files per directory: 64
         journal log file location: in filesystem
         journal log file size: 64MB (67108864 bytes)
         journal log flags:
 tunefs: no changes made
 [KASSERT]
 
 panic: kernel diagnostic assertion "rw_lock_held(&wl->wl_rwlock)" failed: file 
"/local/src/NetBSD/src/sys/kern/vfs_wapbl.c", line 1543
 fatal breakpoint trap in supervisor mode
 trap type 1 code 0 rip ffffffff80228eb5 cs 8 rflags 246 cr2 7f7ffdb05000 cpl 0 
rsp ffff8000495716b0
 Stopped in pid 136.1 (tunefs) at        netbsd:breakpoint+0x5:  leave
 
 -- 
 Nicolas Joly
 
 Biological Software and Databanks.
 Institut Pasteur, Paris.