> > You've deadlocked.  The problem is that ip_join_allmulti() has bumped the
 > > refcount on the ill and is waiting to enter the IPSQ, while the current
 > > thread inside the IPSQ is waiting for the ill refcounts to drop
 > > (ipsq_waitfor is 2 AKA ILL_DOWN).  This is exactly the sort of problem I
 > > was worried about when I warned about using ipsq_enter() a few weeks back.
 > > You should use ipsq_try_enter(), which will enqueue the request if it
 > > cannot immediately complete.
 > 
 > This is a major bummer, as the caller of ip_join_allmulti() doesn't have
 > a STREAMS queue to pass in so that ipsq_try_enter() can work.  It's kind
 > of silly that the ipsq itself doesn't simply have some utility STREAMS
 > queue that it can use for this purpose...

:-(  Another approach would be to acquire a soft reference using
ill_waiter_inc(), drop the ill reference, and then do an ipsq_enter().
Note that ipsq_enter() can fail in that case if you race with a teardown
(ILL_CONDEMNED will be set), in which case you'll want to give up.

-- 
meem

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