From owner-freebsd-stable@FreeBSD.ORG Fri Jan 16 14:14:19 2009 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3CA62106564A; Fri, 16 Jan 2009 14:14:19 +0000 (UTC) (envelope-from petefrench@ticketswitch.com) Received: from constantine.ticketswitch.com (constantine.ticketswitch.com [IPv6:2002:57e0:1d4e:1::3]) by mx1.freebsd.org (Postfix) with ESMTP id EB1308FC1A; Fri, 16 Jan 2009 14:14:18 +0000 (UTC) (envelope-from petefrench@ticketswitch.com) Received: from dilbert.rattatosk ([10.64.50.6] helo=dilbert.ticketswitch.com) by constantine.ticketswitch.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.69 (FreeBSD)) (envelope-from ) id 1LNpSj-000HPJ-PW; Fri, 16 Jan 2009 14:14:17 +0000 Received: from petefrench by dilbert.ticketswitch.com with local (Exim 4.69 (FreeBSD)) (envelope-from ) id 1LNpSj-0004n7-Na; Fri, 16 Jan 2009 14:14:17 +0000 To: rwatson@FreeBSD.org In-Reply-To: Message-Id: From: Pete French Date: Fri, 16 Jan 2009 14:14:17 +0000 Cc: freebsd-stable@freebsd.org, drosih@rpi.edu, dchagin@freebsd.org, rblayzor.bulk@inoc.net Subject: Re: Big problems with 7.1 locking up :-( X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 16 Jan 2009 14:14:19 -0000 > I rather feared as much. Let's run down the path of "perhaps there's a > problem with the new UDP locking code" for a bit and see where it takes us. > Is it possible to run those boxes with WITNESS -- I believe that the fact that > "show alllocks" is failing is because WITNESS isn't present. Yes, I can do that. The only reason I wasn't running with WITNESS is that it didn't lock up when I added the BREAK_TO_DEBUGGER so I was seeing if a simple GENERIC kernel would lock up when I added that. I will go back and add WITNESS when you tell me theres nothing more we can get out of this lock up (recompiling will involve restarting the machine so I loose the 'boekn to debugger' state). Should I add anything else ? Skip spinlocks ? Invariants ? > The other thing we can do is revert UDP to using purely write locks -- the > risk there is that it might change the timing but not actually resolve the > bug, so if we can analyze it a bit using WITNESS first that would be useful. Yes, I will run with WITNESS and anything else you might want. Is there anything else you, or anyone else, wants from this kernel ? It may take another day to lock up when I've restarted it unfortunately. -pete.