| Message ID | 1357944049-29620-12-git-send-email-yinghai@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Friday, January 11, 2013 02:40:38 PM Yinghai Lu wrote: > From: Jiang Liu <jiang.liu@huawei.com> > > The code in pci_root_hp.c depends on function acpi_is_root_bridge() > to check whether an ACPI object is a PCI host bridge or not. > If an ACPI device hasn't been created for the ACPI object yet, > function acpi_is_root_bridge() will return false even if the object > is a PCI host bridge object. That behavior will cause two issues: > 1) No ACPI notification handler installed for PCI host bridges absent > at startup, so hotplug events for those bridges won't be handled. > 2) rescan_root_bridge() can't reenumerate offlined PCI host bridges > because the ACPI devices have been already destroyed. > > So use acpi_match_object_info_ids() to correctly detect PCI host bridges. > > -v2: update to use acpi_match_object_info_ids() from Tang Chen - Yinghai > -v3: drop the PNP0A008, according to Bjorn. > > Signed-off-by: Jiang Liu <jiang.liu@huawei.com> > Signed-off-by: Yinghai Lu <yinghai@kernel.org> > Cc: Len Brown <lenb@kernel.org> > Cc: linux-acpi@vger.kernel.org > --- > drivers/acpi/pci_root.c | 19 ++++++++++++++++++- > 1 file changed, 18 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c > index 5ae36d8..d30fb94 100644 > --- a/drivers/acpi/pci_root.c > +++ b/drivers/acpi/pci_root.c > @@ -923,6 +923,23 @@ static void handle_hotplug_event_root(acpi_handle handle, u32 type, > _handle_hotplug_event_root); > } > > +static bool acpi_is_root_bridge_object(acpi_handle handle) > +{ > + struct acpi_device_info *info = NULL; > + acpi_status status; > + bool ret; > + > + status = acpi_get_object_info(handle, &info); > + if (ACPI_FAILURE(status)) > + return false; > + > + ret = !acpi_match_object_info_ids(info, root_device_ids); > + Well, I kind of don't understand why don't we check info->flags against ACPI_PCI_ROOT_BRIDGE that acpi_get_object_info() sets for us if it finds a PCI root bridge? > + kfree(info); > + > + return ret; > +} > + > static acpi_status __init > find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv) > { > @@ -931,7 +948,7 @@ find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv) > .pointer = objname }; > int *count = (int *)context; > > - if (!acpi_is_root_bridge(handle)) > + if (!acpi_is_root_bridge_object(handle)) > return AE_OK; > > (*count)++; > Thanks, Rafael
On 01/13/2013 07:34 AM, Rafael J. Wysocki wrote: > On Friday, January 11, 2013 02:40:38 PM Yinghai Lu wrote: >> From: Jiang Liu <jiang.liu@huawei.com> >> >> The code in pci_root_hp.c depends on function acpi_is_root_bridge() >> to check whether an ACPI object is a PCI host bridge or not. >> If an ACPI device hasn't been created for the ACPI object yet, >> function acpi_is_root_bridge() will return false even if the object >> is a PCI host bridge object. That behavior will cause two issues: >> 1) No ACPI notification handler installed for PCI host bridges absent >> at startup, so hotplug events for those bridges won't be handled. >> 2) rescan_root_bridge() can't reenumerate offlined PCI host bridges >> because the ACPI devices have been already destroyed. >> >> So use acpi_match_object_info_ids() to correctly detect PCI host bridges. >> >> -v2: update to use acpi_match_object_info_ids() from Tang Chen - Yinghai >> -v3: drop the PNP0A008, according to Bjorn. >> >> Signed-off-by: Jiang Liu <jiang.liu@huawei.com> >> Signed-off-by: Yinghai Lu <yinghai@kernel.org> >> Cc: Len Brown <lenb@kernel.org> >> Cc: linux-acpi@vger.kernel.org >> --- >> drivers/acpi/pci_root.c | 19 ++++++++++++++++++- >> 1 file changed, 18 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c >> index 5ae36d8..d30fb94 100644 >> --- a/drivers/acpi/pci_root.c >> +++ b/drivers/acpi/pci_root.c >> @@ -923,6 +923,23 @@ static void handle_hotplug_event_root(acpi_handle handle, u32 type, >> _handle_hotplug_event_root); >> } >> >> +static bool acpi_is_root_bridge_object(acpi_handle handle) >> +{ >> + struct acpi_device_info *info = NULL; >> + acpi_status status; >> + bool ret; >> + >> + status = acpi_get_object_info(handle, &info); >> + if (ACPI_FAILURE(status)) >> + return false; >> + >> + ret = !acpi_match_object_info_ids(info, root_device_ids); >> + > > Well, I kind of don't understand why don't we check info->flags > against ACPI_PCI_ROOT_BRIDGE that acpi_get_object_info() sets for us if it > finds a PCI root bridge? Hi Rafael, Thanks for reminder, we should test ACPI_PCI_ROOT_BRIDGE flag instead of a redundant calling to acpi_match_object_info_ids(). To be honest, I don't know the existence of ACPI_PCI_ROOT_BRIDGE flag before:( > >> + kfree(info); >> + >> + return ret; >> +} >> + >> static acpi_status __init >> find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv) >> { >> @@ -931,7 +948,7 @@ find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv) >> .pointer = objname }; >> int *count = (int *)context; >> >> - if (!acpi_is_root_bridge(handle)) >> + if (!acpi_is_root_bridge_object(handle)) >> return AE_OK; >> >> (*count)++; >> > > Thanks, > Rafael > > -- 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/acpi/pci_root.c b/drivers/acpi/pci_root.c index 5ae36d8..d30fb94 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -923,6 +923,23 @@ static void handle_hotplug_event_root(acpi_handle handle, u32 type, _handle_hotplug_event_root); } +static bool acpi_is_root_bridge_object(acpi_handle handle) +{ + struct acpi_device_info *info = NULL; + acpi_status status; + bool ret; + + status = acpi_get_object_info(handle, &info); + if (ACPI_FAILURE(status)) + return false; + + ret = !acpi_match_object_info_ids(info, root_device_ids); + + kfree(info); + + return ret; +} + static acpi_status __init find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv) { @@ -931,7 +948,7 @@ find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv) .pointer = objname }; int *count = (int *)context; - if (!acpi_is_root_bridge(handle)) + if (!acpi_is_root_bridge_object(handle)) return AE_OK; (*count)++;