I should be more clear - there are a couple of reasons why I don't think 
Roland's patch is the cause, or a fix, for this problem. First, because when I 
dug through QLogic's bug database I found incidents like this going back to 
2007. Second, when I first began looking at this I noticed the patch and built 
a version that moved the cancel_delayed_work() calls in ib_cancel_rmpp_recvs() 
back inside the locked area and the problem still occurred.

Finally, I should note that this isn't a spinlock type hang; what's happening 
is that destroy_rmpp_recv() appears to be sleeping, waiting for a completion 
that never arrives. I'm guessing that what is going on is that the reference 
count in an rmpp_recv is wrong, but what is causing the problem is unknown. 

-----Original Message-----
From: [email protected] 
[mailto:[email protected]] On Behalf Of Mike Heinz
Sent: Monday, May 03, 2010 1:07 PM
To: Hefty, Sean
Cc: LINUX-RDMA
Subject: RE: Hang in ib_umad when attempting to unregister.

Ah. Got it. Thanks.

They do seem to be related. 0e442afd92fcdde2cc63b6f25556b8934e42b7d2 seems to 
be directly related - but I think that fix is already in OFED 1.5:

core_0310-IB-mad-Fix-lock-lock-timer-deadlock-in-RMPP-code.patch

seems to be the same patch as 0e442afd92fcdde2cc63b6f25556b8934e42b7d2.

-----Original Message-----
From: Hefty, Sean [mailto:[email protected]] 
Sent: Monday, May 03, 2010 12:40 PM
To: Mike Heinz
Subject: RE: Hang in ib_umad when attempting to unregister.

>Where did you get those commit #s? I looked in my local copy of
>
>git://git.openfabrics.org/ofed_1_5/linux-2.6
>
>and they don't seem to be valid objects for that repo. Am I pulling from the
>wrong place?

These are from the upstream kernel.

>commit 6b2eef8fd78ff909c3396b8671d57c42559cc51d
>commit 0e442afd92fcdde2cc63b6f25556b8934e42b7d2

--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to