PCI: acpiphp: Re-enumerate devices when host bridge receives Bus Check
When a PCI host bridge device receives a Bus Check notification, we
must re-enumerate starting with the bridge to discover changes (devices
that have been added or removed).
Prior to 668192b678 ("PCI: acpiphp: Move host bridge hotplug to
pci_root.c"), this happened in _handle_hotplug_event_bridge(). After that
commit, _handle_hotplug_event_bridge() is not installed for host bridges,
and the host bridge notify handler, _handle_hotplug_event_root() did not
re-enumerate.
This patch adds re-enumeration to _handle_hotplug_event_root().
This fixes cases where we don't notice the addition or removal of
PCI devices, e.g., the PCI-to-USB ExpressCard in the bugzilla below.
[bhelgaas: changelog, references]
Reference: https://lkml.kernel.org/r/CAAh6nkmbKR3HTqm5ommevsBwhL_u0N8Rk7Wsms_LfP=nBgKNew@mail.gmail.com
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=57961
Reported-by: Gavin Guo <tuffkidtt@gmail.com>
Tested-by: Gavin Guo <tuffkidtt@gmail.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CC: stable@vger.kernel.org # v3.9+
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 96fed19..716aa93 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -950,6 +950,20 @@
return AE_OK ;
}
+void acpiphp_check_host_bridge(acpi_handle handle)
+{
+ struct acpiphp_bridge *bridge;
+
+ bridge = acpiphp_handle_to_bridge(handle);
+ if (bridge) {
+ acpiphp_check_bridge(bridge);
+ put_bridge(bridge);
+ }
+
+ acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
+ ACPI_UINT32_MAX, check_sub_bridges, NULL, NULL, NULL);
+}
+
static void _handle_hotplug_event_bridge(struct work_struct *work)
{
struct acpiphp_bridge *bridge;