From owner-svn-src-head@FreeBSD.ORG Tue Sep 25 22:10:15 2012 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 404BE1065670; Tue, 25 Sep 2012 22:10:15 +0000 (UTC) (envelope-from emaste@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id 2CB5F8FC14; Tue, 25 Sep 2012 22:10:15 +0000 (UTC) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.4/8.14.4) with ESMTP id q8PMAFTS003953; Tue, 25 Sep 2012 22:10:15 GMT (envelope-from emaste@svn.freebsd.org) Received: (from emaste@localhost) by svn.freebsd.org (8.14.4/8.14.4/Submit) id q8PMAEx5003950; Tue, 25 Sep 2012 22:10:14 GMT (envelope-from emaste@svn.freebsd.org) Message-Id: <201209252210.q8PMAEx5003950@svn.freebsd.org> From: Ed Maste Date: Tue, 25 Sep 2012 22:10:14 +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: r240938 - head/sys/net X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.5 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: Tue, 25 Sep 2012 22:10:15 -0000 Author: emaste Date: Tue Sep 25 22:10:14 2012 New Revision: 240938 URL: http://svn.freebsd.org/changeset/base/240938 Log: Avoid INVARIANTS panic destroying an in-use tap(4) The requirement (implied by the KASSERT in tap_destroy) that the tap is closed isn't valid; destroy_dev will block in devdrn while other threads are in d_* functions. Note: if_tun had the same issue, addressed in SVN revisions r186391, r186483 and r186497. The use of the condvar there appears to be redundant with the functionality provided by destroy_dev. Sponsored by: ADARA Networks Reviewed by: dwhite MFC after: 2 weeks Modified: head/sys/net/if_tap.c head/sys/net/if_tapvar.h Modified: head/sys/net/if_tap.c ============================================================================== --- head/sys/net/if_tap.c Tue Sep 25 21:33:36 2012 (r240937) +++ head/sys/net/if_tap.c Tue Sep 25 22:10:14 2012 (r240938) @@ -213,14 +213,10 @@ tap_destroy(struct tap_softc *tp) { struct ifnet *ifp = tp->tap_ifp; - /* Unlocked read. */ - KASSERT(!(tp->tap_flags & TAP_OPEN), - ("%s flags is out of sync", ifp->if_xname)); - CURVNET_SET(ifp->if_vnet); + destroy_dev(tp->tap_dev); seldrain(&tp->tap_rsel); knlist_destroy(&tp->tap_rsel.si_note); - destroy_dev(tp->tap_dev); ether_ifdetach(ifp); if_free(ifp); Modified: head/sys/net/if_tapvar.h ============================================================================== --- head/sys/net/if_tapvar.h Tue Sep 25 21:33:36 2012 (r240937) +++ head/sys/net/if_tapvar.h Tue Sep 25 22:10:14 2012 (r240938) @@ -64,6 +64,7 @@ struct tap_softc { SLIST_ENTRY(tap_softc) tap_next; /* next device in chain */ struct cdev *tap_dev; struct mtx tap_mtx; /* per-softc mutex */ + struct cv tap_cv; /* protect ref'd dev destroy */ }; #endif /* !_NET_IF_TAPVAR_H_ */