From owner-freebsd-current@FreeBSD.ORG Fri Nov 5 07:39:15 2010 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5C2A0106564A; Fri, 5 Nov 2010 07:39:15 +0000 (UTC) (envelope-from avg@freebsd.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 7537C8FC08; Fri, 5 Nov 2010 07:39:14 +0000 (UTC) Received: from porto.topspin.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id JAA08050; Fri, 05 Nov 2010 09:39:13 +0200 (EET) (envelope-from avg@freebsd.org) Received: from localhost.topspin.kiev.ua ([127.0.0.1]) by porto.topspin.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1PEGtE-000HWJ-No; Fri, 05 Nov 2010 09:39:12 +0200 Message-ID: <4CD3B4A0.6060207@freebsd.org> Date: Fri, 05 Nov 2010 09:39:12 +0200 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.2.12) Gecko/20101029 Lightning/1.0b2 Thunderbird/3.1.6 MIME-Version: 1.0 To: freebsd-current@freebsd.org, freebsd-fs@freebsd.org References: <4CD2656D.8050701@icyb.net.ua> <4CD2C706.6000100@icyb.net.ua> In-Reply-To: <4CD2C706.6000100@icyb.net.ua> X-Enigmail-Version: 1.1.2 Content-Type: text/plain; charset=x-viet-vps Content-Transfer-Encoding: 7bit Cc: Subject: Re: processes stuck on a vnode lock X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Nov 2010 07:39:15 -0000 on 04/11/2010 16:45 Andriy Gapon said the following: > on 04/11/2010 09:49 Andriy Gapon said the following: >> >> I see a few processes stuck on the same vnode, trying to take or to upgrade to >> an exclusive lock on it, while the lock data suggests that it is already >> shared-locked. The vnode is a root vnode of one of ZFS filesystems (it's not a >> global root). >> >> I couldn't find any (other) threads that could actually hold the vnode lock, but >> lock shared count is suspiciously or coincidentally the same as number of >> threads in zfs_root call. > > BTW, I still have the system alive and online, so if anyone has ideas I can try them. > The kernel is not live now, but I have saved it and vmcore of the system. Kostik, just a pure guesswork here - could r214049 have something to do with this? I looked at the change and it looks completely correct - I don't think that a vnode lock can be leaked by that code. But, OTOH, it has some special handling for VV_ROOT, it's in NFS code and and it's in a right time-frame, so just asking. Here's a link to the start of this report thread: http://thread.gmane.org/gmane.os.freebsd.devel.file-systems/10659/focus=128893 -- Andriy Gapon