From owner-svn-src-all@freebsd.org Tue Dec 31 18:58:30 2019 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 629FE1DB611; Tue, 31 Dec 2019 18:58:30 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 47nNqV2245z4b67; Tue, 31 Dec 2019 18:58:30 +0000 (UTC) (envelope-from mav@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 mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 3FFD71E972; Tue, 31 Dec 2019 18:58:30 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id xBVIwUrs048910; Tue, 31 Dec 2019 18:58:30 GMT (envelope-from mav@FreeBSD.org) Received: (from mav@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id xBVIwUSh048909; Tue, 31 Dec 2019 18:58:30 GMT (envelope-from mav@FreeBSD.org) Message-Id: <201912311858.xBVIwUSh048909@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mav set sender to mav@FreeBSD.org using -f From: Alexander Motin Date: Tue, 31 Dec 2019 18:58:30 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r356240 - head/sys/netinet X-SVN-Group: head X-SVN-Commit-Author: mav X-SVN-Commit-Paths: head/sys/netinet X-SVN-Commit-Revision: 356240 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 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: Tue, 31 Dec 2019 18:58:30 -0000 Author: mav Date: Tue Dec 31 18:58:29 2019 New Revision: 356240 URL: https://svnweb.freebsd.org/changeset/base/356240 Log: Relax locking of carp_forus(). This fixes deadlock between CARP and bridge. Bridge calls this function taking CARP lock while holding bridge lock. Same time CARP tries to send its announcements via the bridge while holding CARP lock. Use of CARP_LOCK() here does not solve anything, since sc_addr is constant while race on sc_state is harmless and use of the lock does not close it. Reviewed by: glebius MFC after: 2 weeks Sponsored by: iXsystems, Inc. Modified: head/sys/netinet/ip_carp.c Modified: head/sys/netinet/ip_carp.c ============================================================================== --- head/sys/netinet/ip_carp.c Tue Dec 31 18:28:25 2019 (r356239) +++ head/sys/netinet/ip_carp.c Tue Dec 31 18:58:29 2019 (r356240) @@ -1230,14 +1230,15 @@ carp_forus(struct ifnet *ifp, u_char *dhost) CIF_LOCK(ifp->if_carp); IFNET_FOREACH_CARP(ifp, sc) { - CARP_LOCK(sc); + /* + * CARP_LOCK() is not here, since would protect nothing, but + * cause deadlock with if_bridge, calling this under its lock. + */ if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), ETHER_ADDR_LEN)) { - CARP_UNLOCK(sc); CIF_UNLOCK(ifp->if_carp); return (1); } - CARP_UNLOCK(sc); } CIF_UNLOCK(ifp->if_carp);