From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id 36B247CA4 for ; Tue, 6 Sep 2016 16:54:10 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay1.corp.sgi.com (Postfix) with ESMTP id E04698F8037 for ; Tue, 6 Sep 2016 14:54:06 -0700 (PDT) Received: from mx5-phx2.redhat.com (mx5-phx2.redhat.com [209.132.183.37]) by cuda.sgi.com with ESMTP id S2QENK5FmuYrkSVV (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Tue, 06 Sep 2016 14:54:04 -0700 (PDT) Date: Tue, 6 Sep 2016 17:53:59 -0400 (EDT) From: CAI Qian Message-ID: <58974432.234567.1473198839605.JavaMail.zimbra@redhat.com> In-Reply-To: <20160903003919.GI30056@dastard> References: <723420070.1340881.1472835555274.JavaMail.zimbra@redhat.com> <1832555471.1341372.1472835736236.JavaMail.zimbra@redhat.com> <20160903003919.GI30056@dastard> Subject: Re: xfs_file_splice_read: possible circular locking dependency detected MIME-Version: 1.0 List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: linux-xfs , Linus Torvalds , Al Viro , xfs@oss.sgi.com ----- Original Message ----- > Fundamentally a splice infrastructure problem. If we let splice race > with hole punch and other fallocate() based extent manipulations to > avoid this lockdep warning, we allow potential for read or write to > regions of the file that have been freed. We can live with having > lockdep complain about this potential deadlock as it is unlikely to > ever occur in practice. The other option is simply not an acceptible > solution.... The problem with living with having this lockdep complain that it seems once this lockdep happens, it will prevent other complains from showing up. For example, I have to apply the commit dc3a04d to fix an early rcu lockdep first during the bisecting. CAI Qian _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs