From owner-svn-src-all@FreeBSD.ORG Sun Feb 8 19:55:03 2009 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C484E106566C; Sun, 8 Feb 2009 19:55:03 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id AEEFC8FC20; Sun, 8 Feb 2009 19:55:03 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id n18Jt3UP032531; Sun, 8 Feb 2009 19:55:03 GMT (envelope-from kib@svn.freebsd.org) Received: (from kib@localhost) by svn.freebsd.org (8.14.3/8.14.3/Submit) id n18Jt3Po032530; Sun, 8 Feb 2009 19:55:03 GMT (envelope-from kib@svn.freebsd.org) Message-Id: <200902081955.n18Jt3Po032530@svn.freebsd.org> From: Konstantin Belousov Date: Sun, 8 Feb 2009 19:55:03 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Subject: svn commit: r188323 - head/sys/vm X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 08 Feb 2009 19:55:04 -0000 Author: kib Date: Sun Feb 8 19:55:03 2009 New Revision: 188323 URL: http://svn.freebsd.org/changeset/base/188323 Log: Lock the new map in vmspace_fork(). The newly allocated map should not be accessible outside vmspace_fork() yet, but locking it would satisfy the protocol of the vm_map_entry_link() and other functions called from vmspace_fork(). Use trylock that is supposedly cannot fail, to silence WITNESS warning of the nested acquisition of the sx lock with the same name. Suggested and reviewed by: tegge Modified: head/sys/vm/vm_map.c Modified: head/sys/vm/vm_map.c ============================================================================== --- head/sys/vm/vm_map.c Sun Feb 8 19:53:37 2009 (r188322) +++ head/sys/vm/vm_map.c Sun Feb 8 19:55:03 2009 (r188323) @@ -2679,6 +2679,7 @@ vmspace_fork(struct vmspace *vm1) vm_map_entry_t old_entry; vm_map_entry_t new_entry; vm_object_t object; + int locked; vm_map_lock(old_map); @@ -2689,6 +2690,8 @@ vmspace_fork(struct vmspace *vm1) vm2->vm_daddr = vm1->vm_daddr; vm2->vm_maxsaddr = vm1->vm_maxsaddr; new_map = &vm2->vm_map; /* XXX */ + locked = vm_map_trylock(new_map); /* trylock to silence WITNESS */ + KASSERT(locked, ("vmspace_fork: lock failed")); new_map->timestamp = 1; old_entry = old_map->header.next; @@ -2780,6 +2783,8 @@ vmspace_fork(struct vmspace *vm1) } unlock_and_return: vm_map_unlock(old_map); + if (vm2 != NULL) + vm_map_unlock(new_map); return (vm2); }