From owner-freebsd-current Sun Oct 6 8:36:57 2002 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8DE1837B401; Sun, 6 Oct 2002 08:36:56 -0700 (PDT) Received: from troutmask.apl.washington.edu (troutmask.apl.washington.edu [128.208.78.105]) by mx1.FreeBSD.org (Postfix) with ESMTP id 32CB543E65; Sun, 6 Oct 2002 08:36:56 -0700 (PDT) (envelope-from sgk@troutmask.apl.washington.edu) Received: from troutmask.apl.washington.edu (localhost [127.0.0.1]) by troutmask.apl.washington.edu (8.12.6/8.12.5) with ESMTP id g96Fat4G022134; Sun, 6 Oct 2002 08:36:55 -0700 (PDT) (envelope-from sgk@troutmask.apl.washington.edu) Received: (from sgk@localhost) by troutmask.apl.washington.edu (8.12.6/8.12.6/Submit) id g96FatiA022133; Sun, 6 Oct 2002 08:36:55 -0700 (PDT) Date: Sun, 6 Oct 2002 08:36:55 -0700 From: Steve Kargl To: Brian Fundakowski Feldman Cc: current@FreeBSD.ORG Subject: Re: vnode locking screwed up in src/sys/ufs/ffs/ffs_snapshot.c:ffs_snapshot() Message-ID: <20021006153655.GA22115@troutmask.apl.washington.edu> References: <200210051546.g95FkkX1008580@green.bikeshed.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200210051546.g95FkkX1008580@green.bikeshed.org> User-Agent: Mutt/1.4i Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Sat, Oct 05, 2002 at 11:46:45AM -0400, Brian Fundakowski Feldman wrote: > I got a crash today because "xvp" did not have an interlock when the > call was made to vn_lock(LK_INTERLOCK): > 407 if (snapdebug) > 408 vprint("ffs_snapshot: busy vnode", xvp); > 409 if (vn_lock(xvp, LK_EXCLUSIVE | LK_INTERLOCK, td) != 0) > 410 goto loop; > 411 xp = VTOI(xvp); > 412 > > I don't in fact see any reason why "xvp" would have been locked already > and that this could possibly be valid in the face of a mountpoint which > had any vnodes at all open. This occurred on fscking my "/tmp" > filesystem because of crashes (due to an SSE utilization bug in the > kernel, it seems), which I'm sure was a filesystem in heavy use already. > > Does anyone have any insight on what the correct fix to this is? I > don't have any idea exactly how to correct the locking in this function. > Thanks for insight! > I had the exact same panic while doing a background fsck on /var. I sent the kernel trace to the list yesterday, and forwarded to Kirk. -- Steve To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message