BUG: soft lockup - is this XFS problem?

[Nick Piggin]

On Tue, Dec 23, 2008 at 12:12:59PM -0500, Christoph Hellwig wrote:
> 
> Nick, I've seen various reports like this by Roman.  It seems to be
> caused by an interaction of the lockless pagecache with the xfs
> I/O code.  Any idea what might be wrong here:

Hmm, it could get into a loop here if there is a page in the pagecache
with a zero refcount, which might be a problem with XFS... other looping
conditions might indicate a problem iwth lockless pagecache or radix
tree. It would be very helpful to know what condition it is looping on...