| Message ID | 1357944049-29620-7-git-send-email-yinghai@kernel.org |
|---|---|
| State | Superseded |
| Headers | show |
On Friday, January 11, 2013 02:40:33 PM Yinghai Lu wrote: > From: Jiang Liu <jiang.liu@huawei.com> > > 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. It doesn't look like BUS_NOTIFY_ADD_DEVICE is used by the PCI bus type in the mainline. Is it in linux-next? If not, then I don't see why we need this patch. Thanks, Rafael > 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 847f3ca..5f9c728 100644 > --- a/drivers/pci/bus.c > +++ b/drivers/pci/bus.c > @@ -200,7 +200,7 @@ 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 48b35e1..dc4fde3 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); > >
On 01/13/2013 06:34 AM, Rafael J. Wysocki wrote: > On Friday, January 11, 2013 02:40:33 PM Yinghai Lu wrote: >> From: Jiang Liu <jiang.liu@huawei.com> >> >> 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. > > It doesn't look like BUS_NOTIFY_ADD_DEVICE is used by the PCI bus type > in the mainline. > > Is it in linux-next? > > If not, then I don't see why we need this patch. Hi Rafael, Originally it's a preparation patch for pci_slot/acpiphp/pci_bind related fixups. With recent work from you to remove bind/unbind from struct acpi_bus_type, we have no dependency on this patch anymore. Regards! Gerry > > Thanks, > Rafael > > >> 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 847f3ca..5f9c728 100644 >> --- a/drivers/pci/bus.c >> +++ b/drivers/pci/bus.c >> @@ -200,7 +200,7 @@ 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 48b35e1..dc4fde3 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); >> >> -- 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
On Sun, Jan 13, 2013 at 7:25 AM, Jiang Liu <liuj97@gmail.com> wrote: > On 01/13/2013 06:34 AM, Rafael J. Wysocki wrote: >> On Friday, January 11, 2013 02:40:33 PM Yinghai Lu wrote: >>> From: Jiang Liu <jiang.liu@huawei.com> >>> >>> 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. >> >> It doesn't look like BUS_NOTIFY_ADD_DEVICE is used by the PCI bus type >> in the mainline. >> >> Is it in linux-next? >> >> If not, then I don't see why we need this patch. > Hi Rafael, > Originally it's a preparation patch for pci_slot/acpiphp/pci_bind > related fixups. With recent work from you to remove bind/unbind from struct > acpi_bus_type, we have no dependency on this patch anymore. ok, will drop this one. Yinghai -- 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 847f3ca..5f9c728 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -200,7 +200,7 @@ 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 48b35e1..dc4fde3 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);