From owner-freebsd-stable@FreeBSD.ORG Mon Jun 29 15:01:17 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 0426E10656C0 for ; Mon, 29 Jun 2009 15:01:17 +0000 (UTC) (envelope-from asmrookie@gmail.com) Received: from mail-fx0-f218.google.com (mail-fx0-f218.google.com [209.85.220.218]) by mx1.freebsd.org (Postfix) with ESMTP id 7FB088FC1C for ; Mon, 29 Jun 2009 15:01:16 +0000 (UTC) (envelope-from asmrookie@gmail.com) Received: by mail-fx0-f218.google.com with SMTP id 18so1935191fxm.43 for ; Mon, 29 Jun 2009 08:01:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to:cc :content-type:content-transfer-encoding; bh=xKg12OYQWHFDJsT6+WMacl7qTZHpjlyQZyDpGj3el4s=; b=FY4GTDUQ06KMmyNPMKsaHD1CsR4Y7IdvWeoTtb/NYJGc3pj4d/hY0QWRc5MkO4qESi LiRNouuugDCsHH4skCf+E71/l+X4Jd678NPaIKTDCytaWWKXL/fBZL5egl7NsAu1pexV cGf+1e02CCHkCOkNE5o1JApmwBVP5+PQB0VtI= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=h4IeoJi1/4lMo6Ko/IgfkC/trolsLJdYqvt+Sh5/lX+AqPkTd9+SXo8X1lc48yLPw7 YqPyHV+1b5PZl/F78qidjKOoS4aQGIs97ZbOeakC3pC3LtmhD9Kg3t5foEsW8oJqejit 7TgmDvrPX54s9SfScqf7hfrRkuK+joATQnVAQ= MIME-Version: 1.0 Sender: asmrookie@gmail.com Received: by 10.223.113.9 with SMTP id y9mr4499850fap.19.1246287676104; Mon, 29 Jun 2009 08:01:16 -0700 (PDT) In-Reply-To: References: <3bbf2fe10906290458v3d57441ar44c4ed8f36c957f@mail.gmail.com> <3bbf2fe10906290611j683a0ddawbd524e406e832d54@mail.gmail.com> <3bbf2fe10906290620r7005f47dtfef8becc7f439515@mail.gmail.com> <3bbf2fe10906290706q349211c1pe00cc57cc18a1315@mail.gmail.com> Date: Mon, 29 Jun 2009 17:01:16 +0200 X-Google-Sender-Auth: 2421c93e0afc7a40 Message-ID: <3bbf2fe10906290801l3ed2e04ey44dd5f40f541a714@mail.gmail.com> From: Attilio Rao To: pluknet Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: freebsd-stable Subject: Re: [nfs] process locks in "bo_wwait" on 6.4 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: Mon, 29 Jun 2009 15:01:17 -0000 2009/6/29 pluknet : > 2009/6/29 Attilio Rao : >> 2009/6/29 pluknet : >>> 2009/6/29 Attilio Rao : >>>> 2009/6/29 pluknet : >>>>> 2009/6/29 Attilio Rao : >>>>>> 2009/6/29 pluknet : >>>>>>> 2009/6/29 Attilio Rao : >>>>>>>> 2009/6/29 pluknet : >>>>>>>>> 2009/6/26 pluknet : >>>>>>>>>> 2009/6/26 pluknet : >>>>>>>>>>> Hello. >>>>>>>>>>> >>>>>>>>>>> While building a module on nfs mounted /usr/src >>>>>>>>>>> I got an unkillable process waiting forever in bo_wwait. >>>>>>>>>> >>>>>>>>>> Small note: iface on NFS server has mtu changed from 1500 to 1450. >>>>>>>>>> Can this be a source of the problem? >>>>>>>>> >>>>>>>>> This is 100% reproducible. Lock in the same place. Any hints? >>>>>>>> >>>>>>>> Can you also show the value of ps? >>>>>>>> A precise map of what processes are doing would give an help. >>>>>>>> Also would be useful to printout traces for other threads and not only >>>>>>>> the stucked one. >>>>>>>> >>>>>>> >>>>>>> >From another run: >>>>>> >>>>>> I'm unable to see who would be locking the buffer object in question. >>>>>> Do you have INVARIANT_SUPPORT/INVARIANTS on? >>>>> >>>>> Yes, I do both. >>>>> >>>>>> What revision of /usr/src/sys/kern/vfs_bio.c are you running with? >>>>>> >>>>> >>>>> As of 6.4-R: CVS rev 1.491.2.12.4.1 / SVN rev 183531. >>>> >>>> Please try this patch and report. >>>> >>>> Thanks, >>>> Attilio >>>> >>>> --- src/sys/nfsclient/nfs_vnops.c 2008/02/13 20:44:18 1.281 >>>> +++ src/sys/nfsclient/nfs_vnops.c 2008/03/22 09:15:15 1.282 >>>> @@ -33,7 +33,7 @@ >>>> */ >>>> >>>> #include >>>> -__FBSDID("$FreeBSD: >>>> /usr/local/www/cvsroot/FreeBSD/src/sys/nfsclient/nfs_vnops.c,v 1.281 >>>> 2008/02/13 20:44:18 attilio Exp $"); >>>> +__FBSDID("$FreeBSD: >>>> /usr/local/www/cvsroot/FreeBSD/src/sys/nfsclient/nfs_vnops.c,v 1.282 >>>> 2008/03/22 09:15:15 jeff Exp $"); >>>> >>> >>> Do you refer to the whole svn r177493, or is its nfs part will be enough? >>> This only vfs_vnops.c diff seems not applicable without underneath >>> kernel part changes. >>> >>> I'll try. Thanks. >> >> The NFS part should be enough, though I don't understand why it >> doesn't trigger a panic on STABLE_6 as long as, at least in my >> revision, there is an assert for the buffer object lock to be held in >> bufobj_wwait(). What's your sys/kern/vfs_bio.c rev? >> > > As of 6.4-R. > $FreeBSD: src/sys/kern/vfs_bio.c,v 1.491.2.12.4.1 2008/10/02 02:57:24 > kensmith Exp $ That's it, the revision doesn't have the assert. If it does fix the problem for you, I will let you test a more comprehensive patch as there is also at least another fix I want to bring in along with this one (and the relative asserts). Thanks, Attilio -- Peace can only be achieved by understanding - A. Einstein