Date: Tue, 31 Jan 2012 18:20:14 GMT From: dfilter@FreeBSD.ORG (dfilter service) To: freebsd-xen@FreeBSD.org Subject: Re: kern/154302: commit references a PR Message-ID: <201201311820.q0VIKEF8073390@freefall.freebsd.org>
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The following reply was made to PR kern/154302; it has been noted by GNATS. From: dfilter@FreeBSD.ORG (dfilter service) To: bug-followup@FreeBSD.org Cc: Subject: Re: kern/154302: commit references a PR Date: Tue, 31 Jan 2012 18:13:59 +0000 (UTC) Author: gibbs Date: Tue Jan 31 18:13:49 2012 New Revision: 230831 URL: http://svn.freebsd.org/changeset/base/230831 Log: MFC r225708 into stable/8: 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 Modified: stable/8/sys/dev/xen/netfront/netfront.c Directory Properties: stable/8/sys/ (props changed) stable/8/sys/amd64/include/xen/ (props changed) stable/8/sys/cddl/contrib/opensolaris/ (props changed) stable/8/sys/contrib/dev/acpica/ (props changed) stable/8/sys/contrib/pf/ (props changed) Modified: stable/8/sys/dev/xen/netfront/netfront.c ============================================================================== --- stable/8/sys/dev/xen/netfront/netfront.c Tue Jan 31 17:51:30 2012 (r230830) +++ stable/8/sys/dev/xen/netfront/netfront.c Tue Jan 31 18:13:49 2012 (r230831) @@ -402,11 +402,33 @@ 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++) { @@ -447,7 +469,7 @@ 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 @@ -457,7 +479,7 @@ netfront_attach(device_t dev) &xn_enable_lro, 0, "Large Receive Offload"); #endif - return 0; + return (0); } @@ -2020,11 +2042,8 @@ 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); @@ -2066,8 +2085,7 @@ create_netdev(device_t dev) exit: gnttab_free_grant_references(np->gref_tx_head); out: - panic("do something smart"); - + return (err); } /** _______________________________________________ svn-src-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscribe@freebsd.org"
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