lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Sun, 29 Dec 2013 19:30:18 -0800 From: Yinghai Lu <yinghai@...nel.org> To: "Rafael J. Wysocki" <rjw@...ysocki.net> Cc: Bjorn Helgaas <bhelgaas@...gle.com>, Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Linux PCI <linux-pci@...r.kernel.org>, ACPI Devel Maling List <linux-acpi@...r.kernel.org>, LKML <linux-kernel@...r.kernel.org>, Yasuaki Ishimatsu <isimatu.yasuaki@...fujitsu.com>, Tejun Heo <tj@...nel.org> Subject: Re: [PATCH][tentative] PCI / ACPI: Rework PCI host bridge removal to avoid sysfs warnings On Sat, Dec 28, 2013 at 3:20 PM, Rafael J. Wysocki <rjw@...ysocki.net> wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@...el.com> > > The device_del(&host_bridge->dev) in pci_stop_root_bus() is > problematic, because it causes all sysfs directories below > the host bridge to be removed recursively and when > pci_remove_root_bus() attempts to remove devices on the root > bus (whose sysfs directories are gone now along with all their > subdirectories), it causes warnings similar to this one to be > printed: > > WARNING: CPU: 0 PID: 6 at fs/sysfs/group.c:214 sysfs_remove_group+0xc6/0xd0() > sysfs group ffffffff819ac5c0 not found for kobject '0001:ff:10.2' > Modules linked in: <irrelevant list> > CPU: 0 PID: 6 Comm: kworker/u512:0 Tainted: G W 3.13.0-rc5+ #11 > Hardware name: > Workqueue: kacpi_hotplug acpi_hotplug_work_fn > 0000000000000009 ffff8808738d3bd8 ffffffff815d84ea ffff8808738d3c20 > ffff8808738d3c10 ffffffff8106594d 0000000000000000 ffffffff819ac5c0 > ffff880871b9d0a8 ffff8a07d1895000 0000000000000103 ffff8808738d3c70 > Call Trace: > [<ffffffff815d84ea>] dump_stack+0x45/0x56 > [<ffffffff8106594d>] warn_slowpath_common+0x7d/0xa0 > [<ffffffff810659bc>] warn_slowpath_fmt+0x4c/0x50 > [<ffffffff8122b52e>] ? sysfs_get_dirent_ns+0x4e/0x70 > [<ffffffff8122c806>] sysfs_remove_group+0xc6/0xd0 > [<ffffffff813b83f3>] dpm_sysfs_remove+0x43/0x50 > [<ffffffff813ae105>] device_del+0x45/0x1c0 > [<ffffffff812e51f6>] pci_remove_bus_device+0x66/0xd0 > [<ffffffff812e5363>] pci_remove_root_bus+0x73/0x80 > [<ffffffff813276ab>] acpi_pci_root_remove+0x42/0x4f > [<ffffffff81323070>] acpi_bus_trim+0x56/0x89 > [<ffffffff81323052>] acpi_bus_trim+0x38/0x89 > [<ffffffff813245df>] acpi_device_hotplug+0x137/0x33b > [<ffffffff8131efba>] acpi_hotplug_work_fn+0x1c/0x27 > [<ffffffff81080f1b>] process_one_work+0x17b/0x460 > [<ffffffff81081ccb>] worker_thread+0x11b/0x400 > [<ffffffff81081bb0>] ? rescuer_thread+0x3e0/0x3e0 > [<ffffffff81088a12>] kthread+0xd2/0xf0 > [<ffffffff81088940>] ? kthread_create_on_node+0x180/0x180 > [<ffffffff815e823c>] ret_from_fork+0x7c/0xb0 > [<ffffffff81088940>] ? kthread_create_on_node+0x180/0x180 > > To avoid that, the host bridge device has to be deleted after all of > its children, so merge pci_stop_root_bus() and pci_remove_root_bus() > into one function, pci_stop_and_remove_root_bus(), that first will > use pci_stop_and_remove_bus_device() to stop and remove all devices > on the root bus and then will delete the host bridge device, remove > its bus and drop the final reference to it. > > Reported-by: Yasuaki Ishimatsu <isimatu.yasuaki@...fujitsu.com> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com> > --- > > Hi, > > I can't really test this patch, but I don't know how it can break anything. > > The only user of pci_stop_root_bus() and pci_remove_root_bus() is > acpi_pci_root_remove() and the code ordering there seems to be somewhat > arbitrary. If you are aware of any reason why it may not work, please let > me know. :-) > > Thanks, > Rafael > > --- > drivers/acpi/pci_root.c | 4 +--- > drivers/pci/remove.c | 23 ++++------------------- > include/linux/pci.h | 3 +-- > 3 files changed, 6 insertions(+), 24 deletions(-) > > Index: linux-pm/drivers/acpi/pci_root.c > =================================================================== > --- linux-pm.orig/drivers/acpi/pci_root.c > +++ linux-pm/drivers/acpi/pci_root.c > @@ -611,12 +611,10 @@ static void acpi_pci_root_remove(struct > { > struct acpi_pci_root *root = acpi_driver_data(device); > > - pci_stop_root_bus(root->bus); > - > device_set_run_wake(root->bus->bridge, false); > pci_acpi_remove_bus_pm_notifier(device); > > - pci_remove_root_bus(root->bus); > + pci_stop_and_remove_root_bus(root->bus); > > kfree(root); > } We have patches that need to stop ioapic and iommu between pci_stop_root_bus and pci_remove_root_bus. Please check if the problem still happen after http://git.kernel.org/cgit/linux/kernel/git/helgaas/pci.git/patch/?id=c4a0a5d964e90b93eb4101c3927b788e083e530f http://git.kernel.org/cgit/linux/kernel/git/helgaas/pci.git/patch/?id=e3b439e1d315aff59c1b4f0fc43c5cd2d82b4138 or just try: git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git pci/deletion Thanks Yinghai -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists