| Message ID | 1357663945-16054-3-git-send-email-jiang.liu@huawei.com |
|---|---|
| State | Superseded |
| Headers | show |
On Wednesday, January 09, 2013 12:52:21 AM Jiang Liu wrote: > When handling BUS_NOTIFY_ADD_DEVICE event for a PCI bridge device, > the notification handler can't hold reference count to the new PCI bus > because the device object for the new bus (pci_dev->subordinate->dev) > hasn't been initialized yet. > > Split the registration of PCI bus device into two stages as below, > so that the event handler could hold reference count to the new PCI bus > when handling BUS_NOTIFY_ADD_DEVICE event. > > 1) device_initialize(&pci_dev->dev) > 2) device_initialize(&pci_dev->subordinate->dev) > 3) notify BUS_NOTIFY_ADD_DEVICE event for pci_dev > 4) device_add(&pci_dev->dev) > 5) device_add(&pci_dev->subordinate->dev) > > Signed-off-by: Jiang Liu <jiang.liu@huawei.com> > Signed-off-by: Yinghai Lu <yinghai@kernel.org> > --- > drivers/pci/bus.c | 2 +- > drivers/pci/probe.c | 4 +++- > drivers/pci/remove.c | 10 +++++----- > 3 files changed, 9 insertions(+), 7 deletions(-) > > diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c > index ad6a8b6..2fea481 100644 > --- a/drivers/pci/bus.c > +++ b/drivers/pci/bus.c > @@ -198,7 +198,7 @@ int pci_bus_add_child(struct pci_bus *bus) > if (bus->bridge) > bus->dev.parent = bus->bridge; > > - retval = device_register(&bus->dev); > + retval = device_add(&bus->dev); > if (retval) > return retval; > > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > index e557d6f..a8315c2 100644 > --- a/drivers/pci/probe.c > +++ b/drivers/pci/probe.c > @@ -642,6 +642,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, > */ > child->dev.class = &pcibus_class; > dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr); > + device_initialize(&child->dev); > > /* > * Set up the primary, secondary and subordinate > @@ -1678,7 +1679,8 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > b->dev.class = &pcibus_class; > b->dev.parent = b->bridge; > dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus); > - error = device_register(&b->dev); > + device_initialize(&b->dev); > + error = device_add(&b->dev); Well, the change here isn't really necessary, as far as I can say. > if (error) > goto class_dev_reg_err; > > diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c > index fc38c48..a1fdd0f 100644 > --- a/drivers/pci/remove.c > +++ b/drivers/pci/remove.c > @@ -48,11 +48,11 @@ void pci_remove_bus(struct pci_bus *bus) > list_del(&bus->node); > pci_bus_release_busn_res(bus); > up_write(&pci_bus_sem); > - if (!bus->is_added) > - return; > - > - pci_remove_legacy_files(bus); > - device_unregister(&bus->dev); > + if (bus->is_added) { > + pci_remove_legacy_files(bus); > + device_del(&bus->dev); > + } > + put_device(&bus->dev); > } > EXPORT_SYMBOL(pci_remove_bus); > > Apart from the above Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On 01/09/2013 07:29 AM, Rafael J. Wysocki wrote: > On Wednesday, January 09, 2013 12:52:21 AM Jiang Liu wrote: snip >> @@ -1678,7 +1679,8 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, >> b->dev.class = &pcibus_class; >> b->dev.parent = b->bridge; >> dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus); >> - error = device_register(&b->dev); >> + device_initialize(&b->dev); >> + error = device_add(&b->dev); > > Well, the change here isn't really necessary, as far as I can say. Hi Rafael, The kernel documentation recommends to pair device_add() with device_del(), so the above change is to follow that recommendation because pci_remove_bus() now invokes device_del(). > >> if (error) >> goto class_dev_reg_err; >> >> diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c >> index fc38c48..a1fdd0f 100644 >> --- a/drivers/pci/remove.c >> +++ b/drivers/pci/remove.c >> @@ -48,11 +48,11 @@ void pci_remove_bus(struct pci_bus *bus) >> list_del(&bus->node); >> pci_bus_release_busn_res(bus); >> up_write(&pci_bus_sem); >> - if (!bus->is_added) >> - return; >> - >> - pci_remove_legacy_files(bus); >> - device_unregister(&bus->dev); >> + if (bus->is_added) { >> + pci_remove_legacy_files(bus); >> + device_del(&bus->dev); >> + } >> + put_device(&bus->dev); >> } >> EXPORT_SYMBOL(pci_remove_bus); >> >> > > Apart from the above > > Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Thanks for your review and Ack. Regards! Gerry -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index ad6a8b6..2fea481 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -198,7 +198,7 @@ int pci_bus_add_child(struct pci_bus *bus) if (bus->bridge) bus->dev.parent = bus->bridge; - retval = device_register(&bus->dev); + retval = device_add(&bus->dev); if (retval) return retval; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index e557d6f..a8315c2 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -642,6 +642,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, */ child->dev.class = &pcibus_class; dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr); + device_initialize(&child->dev); /* * Set up the primary, secondary and subordinate @@ -1678,7 +1679,8 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, b->dev.class = &pcibus_class; b->dev.parent = b->bridge; dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus); - error = device_register(&b->dev); + device_initialize(&b->dev); + error = device_add(&b->dev); if (error) goto class_dev_reg_err; diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index fc38c48..a1fdd0f 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -48,11 +48,11 @@ void pci_remove_bus(struct pci_bus *bus) list_del(&bus->node); pci_bus_release_busn_res(bus); up_write(&pci_bus_sem); - if (!bus->is_added) - return; - - pci_remove_legacy_files(bus); - device_unregister(&bus->dev); + if (bus->is_added) { + pci_remove_legacy_files(bus); + device_del(&bus->dev); + } + put_device(&bus->dev); } EXPORT_SYMBOL(pci_remove_bus);