From owner-svn-src-head@FreeBSD.ORG Wed Sep 21 00:13:04 2011 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 99842106566B; Wed, 21 Sep 2011 00:13:04 +0000 (UTC) (envelope-from gibbs@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id 7EE6F8FC0C; Wed, 21 Sep 2011 00:13:04 +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 p8L0D4cE050851; Wed, 21 Sep 2011 00:13:04 GMT (envelope-from gibbs@svn.freebsd.org) Received: (from gibbs@localhost) by svn.freebsd.org (8.14.4/8.14.4/Submit) id p8L0D4hi050849; Wed, 21 Sep 2011 00:13:04 GMT (envelope-from gibbs@svn.freebsd.org) Message-Id: <201109210013.p8L0D4hi050849@svn.freebsd.org> From: "Justin T. Gibbs" Date: Wed, 21 Sep 2011 00:13:04 +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: r225708 - head/sys/dev/xen/netfront 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: Wed, 21 Sep 2011 00:13:04 -0000 Author: gibbs Date: Wed Sep 21 00:13:04 2011 New Revision: 225708 URL: http://svn.freebsd.org/changeset/base/225708 Log: Modify the netfront driver so it can successfully attach to PV devices with the ioemu attribute set. sys/dev/xen/netfront/netfront.c: o If a mac address for the interface cannot be found in the front-side XenStore tree, look for an entry in the back-side tree. With ioemu devices, the emulator does not populate the front side tree and neither does Xend. o Return an error rather than panic when an attach attempt fails. Reported by: Janne Snabb (fix inspired by patch provided) PR: kern/154302 Approved by: re Modified: head/sys/dev/xen/netfront/netfront.c Modified: head/sys/dev/xen/netfront/netfront.c ============================================================================== --- head/sys/dev/xen/netfront/netfront.c Wed Sep 21 00:08:25 2011 (r225707) +++ head/sys/dev/xen/netfront/netfront.c Wed Sep 21 00:13:04 2011 (r225708) @@ -406,11 +406,33 @@ xen_net_read_mac(device_t dev, uint8_t m { int error, i; char *s, *e, *macstr; + const char *path; - error = xs_read(XST_NIL, xenbus_get_node(dev), "mac", NULL, - (void **) &macstr); - if (error) + path = xenbus_get_node(dev); + error = xs_read(XST_NIL, path, "mac", NULL, (void **) &macstr); + if (error == ENOENT) { + /* + * Deal with missing mac XenStore nodes on devices with + * HVM emulation (the 'ioemu' configuration attribute) + * enabled. + * + * The HVM emulator may execute in a stub device model + * domain which lacks the permission, only given to Dom0, + * to update the guest's XenStore tree. For this reason, + * the HVM emulator doesn't even attempt to write the + * front-side mac node, even when operating in Dom0. + * However, there should always be a mac listed in the + * backend tree. Fallback to this version if our query + * of the front side XenStore location doesn't find + * anything. + */ + path = xenbus_get_otherend_path(dev); + error = xs_read(XST_NIL, path, "mac", NULL, (void **) &macstr); + } + if (error != 0) { + xenbus_dev_fatal(dev, error, "parsing %s/mac", path); return (error); + } s = macstr; for (i = 0; i < ETHER_ADDR_LEN; i++) { @@ -451,7 +473,7 @@ netfront_attach(device_t dev) err = create_netdev(dev); if (err) { xenbus_dev_fatal(dev, err, "creating netdev"); - return err; + return (err); } #if __FreeBSD_version >= 700000 @@ -461,7 +483,7 @@ netfront_attach(device_t dev) &xn_enable_lro, 0, "Large Receive Offload"); #endif - return 0; + return (0); } static int @@ -2067,11 +2089,8 @@ create_netdev(device_t dev) } err = xen_net_read_mac(dev, np->mac); - if (err) { - xenbus_dev_fatal(dev, err, "parsing %s/mac", - xenbus_get_node(dev)); + if (err) goto out; - } /* Set up ifnet structure */ ifp = np->xn_ifp = if_alloc(IFT_ETHER); @@ -2105,8 +2124,7 @@ create_netdev(device_t dev) exit: gnttab_free_grant_references(np->gref_tx_head); out: - panic("do something smart"); - + return (err); } /**