From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753522AbbE1F5M (ORCPT ); Thu, 28 May 2015 01:57:12 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:34036 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752201AbbE1F5J (ORCPT ); Thu, 28 May 2015 01:57:09 -0400 Date: Thu, 28 May 2015 00:54:59 -0500 From: Felipe Balbi To: Sudip Mukherjee CC: Greg KH , Alan Stern , Heikki Krogerus , Tal Shorer , Sasha Levin , USB list , "" , David Cohen , Felipe Balbi , Lu Baolu Subject: Re: [PATCH] usb: ulpi: don't register drivers if bus doesn't exist Message-ID: <20150528055459.GC10509@saruman.tx.rr.com> Reply-To: References: <20150527083933.GA13844@kuha.fi.intel.com> <20150527152116.GA1972@kroah.com> <20150528053938.GB2944@sudip-PC> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="E/DnYTRukya0zdZ1" Content-Disposition: inline In-Reply-To: <20150528053938.GB2944@sudip-PC> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --E/DnYTRukya0zdZ1 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, May 28, 2015 at 11:09:38AM +0530, Sudip Mukherjee wrote: > On Wed, May 27, 2015 at 08:21:16AM -0700, Greg KH wrote: > > On Wed, May 27, 2015 at 11:16:34AM -0400, Alan Stern wrote: > > > On Wed, 27 May 2015, Heikki Krogerus wrote: > >=20 > > Maybe we need to test for this in the driver core, not allowing drivers > > for busses that are not registered, that might solve the main problem > > here. I'll try to look at it tonight. > may i suggest something like this ? > buildtest with allmodconfig and allyesconfig on x86_64. > built and booted on x86. >=20 >=20 > diff --git a/drivers/base/bus.c b/drivers/base/bus.c > index 5005924..95cefa0 100644 > --- a/drivers/base/bus.c > +++ b/drivers/base/bus.c > @@ -943,6 +943,7 @@ int bus_register(struct bus_type *bus) > if (retval) > goto bus_groups_fail; > =20 > + bus->registered =3D true; once set, it's never cleared. > pr_debug("bus: '%s': registered\n", bus->name); > return 0; > =20 > diff --git a/drivers/base/driver.c b/drivers/base/driver.c > index 4eabfe2..1acae5b 100644 > --- a/drivers/base/driver.c > +++ b/drivers/base/driver.c > @@ -150,6 +150,11 @@ int driver_register(struct device_driver *drv) > int ret; > struct device_driver *other; > =20 > + if (!drv->bus->registered) { > + pr_err("Driver %s registration failed. bus not yet registered\n", > + drv->name); > + return -ENODEV; > + } > BUG_ON(!drv->bus->p); > =20 > if ((drv->bus->probe && drv->probe) || > diff --git a/include/linux/device.h b/include/linux/device.h > index 00ac57c..8fe4745 100644 > --- a/include/linux/device.h > +++ b/include/linux/device.h > @@ -126,6 +126,7 @@ struct bus_type { > const struct dev_pm_ops *pm; > =20 > const struct iommu_ops *iommu_ops; > + bool registered; /* DON'T TOUCH THIS */ I would rather use an atomic_t --=20 balbi --E/DnYTRukya0zdZ1 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJVZq2zAAoJEIaOsuA1yqRE0lQP/j6PsHz74CIF0fBe5PsjqVww IbFV5WnWGjt6kQIJ+fpq48KTQMIasfMYLfS+JZ+mbkYX4Zsd2jKIA2KxttQhPjyT LcOb7T6BDjw1fA0zjG3m1uYZGIKpcd/CIR1AzsnyWR13m7nkHCP/bwc2bUF3uuBa DbtJwnI3IyKnJrIYB49nY6qT5eEhGXX3jP8zzTiGiaUsevJ4ccbSvPdIu9MK918L KWdEwHAfOkAeId1knB1VAy8Z562cSbhrbeHYEv9EGbnPsgPtgXYXMdr8XE9JNuSe D8RZdqZ+iFqlkEECUfudyWg7mqP+HBrT3T1JqKLLN3yhHGnguHBj7939+liIgKZw OxyNifjTuShcBIoS+KMqTJ+Bo7n5TJ7qXWPat3KwcdPiuAu23fzybFGhfE62yvT8 tU84xhPtYEqEvJiPDZVAzdmPrt9G0JCdV2QHUPBUJlv2C3LxuJZ96macZuTqxmD0 +ry4OL1xjQX4WzygZXy44XhTpF7m9JQ+gk7lS8/YaC8lVnyhkYm/RkHgEcrFSKxF sMlZ192lg1RhFeHlY814pdReyMeOxvOkc0sQRzWU9fTWjt/PLTnQA6cKyx6v3pHb ELZZELf9WqfuQmayM55SVHL2s7VpH5iUGopkvloz/e08ul00lNvcIUQIlwOfQ0Ot kQx644PhKOJDWL02qJas =9CiX -----END PGP SIGNATURE----- --E/DnYTRukya0zdZ1--