From owner-svn-src-head@freebsd.org Sat May 21 23:18:24 2016 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 414BEB45A25; Sat, 21 May 2016 23:18:24 +0000 (UTC) (envelope-from alc@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 121E61EE2; Sat, 21 May 2016 23:18:24 +0000 (UTC) (envelope-from alc@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id u4LNINaH028626; Sat, 21 May 2016 23:18:23 GMT (envelope-from alc@FreeBSD.org) Received: (from alc@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id u4LNINpB028625; Sat, 21 May 2016 23:18:23 GMT (envelope-from alc@FreeBSD.org) Message-Id: <201605212318.u4LNINpB028625@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: alc set sender to alc@FreeBSD.org using -f From: Alan Cox Date: Sat, 21 May 2016 23:18:23 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r300382 - head/sys/vm X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 21 May 2016 23:18:24 -0000 Author: alc Date: Sat May 21 23:18:23 2016 New Revision: 300382 URL: https://svnweb.freebsd.org/changeset/base/300382 Log: When descending a shadow chain of objects, it makes no sense to update the current offset (spelled: "fs.pindex") until it is known whether a backing object exists. In fact, if not for the fact that the backing object offset is zero when there is no backing object, this update would produce a broken offset. Reviewed by: kib Modified: head/sys/vm/vm_fault.c Modified: head/sys/vm/vm_fault.c ============================================================================== --- head/sys/vm/vm_fault.c Sat May 21 23:14:27 2016 (r300381) +++ head/sys/vm/vm_fault.c Sat May 21 23:18:23 2016 (r300382) @@ -705,7 +705,6 @@ vnode_locked: * Move on to the next object. Lock the next object before * unlocking the current one. */ - fs.pindex += OFF_TO_IDX(fs.object->backing_object_offset); next_object = fs.object->backing_object; if (next_object == NULL) { /* @@ -743,6 +742,8 @@ vnode_locked: vm_object_pip_add(next_object, 1); if (fs.object != fs.first_object) vm_object_pip_wakeup(fs.object); + fs.pindex += + OFF_TO_IDX(fs.object->backing_object_offset); VM_OBJECT_WUNLOCK(fs.object); fs.object = next_object; }