Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755504AbYLEO5T (ORCPT ); Fri, 5 Dec 2008 09:57:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752523AbYLEO5F (ORCPT ); Fri, 5 Dec 2008 09:57:05 -0500 Received: from mx2.redhat.com ([66.187.237.31]:53698 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751919AbYLEO5D (ORCPT ); Fri, 5 Dec 2008 09:57:03 -0500 Subject: Re: [PATCH] virtio: make PCI devices take a virtio_pci module ref From: Mark McLoughlin Reply-To: Mark McLoughlin To: Jiri Slaby Cc: Michael Tokarev , Rusty Russell , linux-kernel , kvm , Anthony Liguori In-Reply-To: <493929D2.4070900@gmail.com> References: <1228394671.3732.77.camel@blaa> <49385DB7.4060306@gmail.com> <4938EE0B.8020501@msgid.tls.msk.ru> <493929D2.4070900@gmail.com> Content-Type: text/plain Date: Fri, 05 Dec 2008 14:55:21 +0000 Message-Id: <1228488921.3858.25.camel@blaa> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3238 Lines: 88 On Fri, 2008-12-05 at 14:17 +0100, Jiri Slaby wrote: > Michael Tokarev napsal(a): > > Jiri Slaby wrote: > >> On 12/04/2008 01:44 PM, Mark McLoughlin wrote: > >>> Nothing takes a ref on virtio_pci, so even if you have > >>> devices in use, rmmod will attempt to unload the module. > >> It unbinds the device properly as any other driver. So what's the problem here? > > > > Here's what we get when rmmod'ing (a zero-refcounted but > > in use) virtio_pci (I did it by a chance, cut-n-pasted > > the wrong line): > > > > WARNING: at drivers/base/core.c:122 device_release+0x5f/0x70() > > Device 'virtio1' does not have a release() function, it is broken and must be fixed. > > Modules linked in: ext3 jbd mbcache acpiphp dock pci_hotplug virtio_net virtio_blk virtio_pci(-) virtio_ring virtio > > > > Pid: 361, comm: rmmod Tainted: G S 2.6.27-i686smp #2.6.27.7 > > [] warn_slowpath+0x6f/0xa0 > > [] prepare_set+0x30/0x80 > > [] __wake_up+0x3e/0x60 > > [] release_sysfs_dirent+0x45/0xb0 > > ... > > So why don't you fix the root cause and add such a crap into the probe > function (not even counting probe can fail later)? > > Fix the virtio bus instead. Yeah, the patch I posted wasn't meant as a fix for this traceback. Here's one that does fix it. Cheers, Mark. From: Mark McLoughlin Subject: [PATCH] virtio: add device release() function Add a release() function for virtio_pci devices so as to avoid: Device 'virtio0' does not have a release() function, it is broken and must be fixed The struct device is embedded in the struct virtio_pci_device which is freed by virtio_pci_remove(), so virtio_pci_release_dev() need not actually do anything. Signed-off-by: Mark McLoughlin --- drivers/virtio/virtio_pci.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c index c7dc37c..7d4899c 100644 --- a/drivers/virtio/virtio_pci.c +++ b/drivers/virtio/virtio_pci.c @@ -70,12 +70,17 @@ static struct pci_device_id virtio_pci_id_table[] = { MODULE_DEVICE_TABLE(pci, virtio_pci_id_table); +static void virtio_pci_release_dev(struct device *dev) +{ +} + /* A PCI device has it's own struct device and so does a virtio device so * we create a place for the virtio devices to show up in sysfs. I think it * would make more sense for virtio to not insist on having it's own device. */ static struct device virtio_pci_root = { .parent = NULL, .bus_id = "virtio-pci", + .release = virtio_pci_release_dev, }; /* Convert a generic virtio device to our structure */ @@ -328,6 +333,7 @@ static int __devinit virtio_pci_probe(struct pci_dev *pci_dev, return -ENOMEM; vp_dev->vdev.dev.parent = &virtio_pci_root; + vp_dev->vdev.dev.release = virtio_pci_release_dev; vp_dev->vdev.config = &virtio_pci_config_ops; vp_dev->pci_dev = pci_dev; INIT_LIST_HEAD(&vp_dev->virtqueues); -- 1.6.0.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/