(ZFS?): panic: lockmgr: locking against myself

Eric Anderson anderson at freebsd.org
Mon Jul 30 11:58:05 UTC 2007


Peter Schuller wrote:
>> Could you paste the output of:
>>
>> 	db> show vnode 0x<addr>
>>
>> Where <addr> is the first argument to vrele() function above.
> 
> I was not able to get ddb to include function arguments in backtraces for some 
> reason, but I inserted a pointer printout before each of the two calls to 
> vrele() in mountcheckdirs().
> 
> Based on the last printout prior to panic, it is the second call in the 
> function (code line wise; i.e., when locking rootvnode) that is triggering 
> the panic, on this vnode:
> 
> vnode 0xffffff00037473e0: tag devfs, type VDIR
>   usecount 0, writecount 0, refcount 1 mountedhere 0xffffff0003745ca0
>   flags (VV_ROOT)
>     lock type devfs: EXCL (count 1) by thread 0xffffff00010e6680 (pid 1)
> 
> Also, this time I triggered it after having dropped a drive (as opposed to 
> when I then booted back up again with two drives).
> 
> Am I understanding this correctly that the root filesystem has suddenly become 
> devfs?
> 


The VV_ROOT flag means that this particular vnode is the root of a file 
system, not that it is *the* root necessarily.


Eric


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