From: Long Li <longli@xxxxxxxxxxxxx>
hv_pci_devices_present is called in hv_pci_remove when we remove a PCI
device from host (e.g. by disabling SRIOV on a device). In hv_pci_remove,
the bus is already removed before the call, so we don't need to rescan the
bus in the workqueue scheduled from hv_pci_devices_present.
By introducing status hv_pcibus_removed, we can avoid this situation.
Signed-off-by: Long Li <longli@xxxxxxxxxxxxx>
Reported-by: Xiaofeng Wang <xiaofwan@xxxxxxxxxx>
Acked-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
---
drivers/pci/host/pci-hyperv.c | 20 +++++++++++++++++---
1 file changed, 17 insertions(+), 3 deletions(-)
diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c
index ada9856..39fafda 100644
--- a/drivers/pci/host/pci-hyperv.c
+++ b/drivers/pci/host/pci-hyperv.c
@@ -350,6 +350,7 @@ enum hv_pcibus_state {
hv_pcibus_init = 0,
hv_pcibus_probed,
hv_pcibus_installed,
+ hv_pcibus_removed,
hv_pcibus_maximum
};
@@ -1504,13 +1505,24 @@ static void pci_devices_present_work(struct work_struct *work)
put_pcichild(hpdev, hv_pcidev_ref_initial);
}
- /* Tell the core to rescan bus because there may have been changes. */
- if (hbus->state == hv_pcibus_installed) {
+ switch(hbus->state) {
+ case hv_pcibus_installed:
+ /*
+ * Tell the core to rescan bus
+ * because there may have been changes.
+ */
pci_lock_rescan_remove();
pci_scan_child_bus(hbus->pci_bus);
pci_unlock_rescan_remove();
- } else {
+ break;
+
+ case hv_pcibus_init:
+ case hv_pcibus_probed:
survey_child_resources(hbus);
+ break;
+
+ default:
+ break;
}
up(&hbus->enum_sem);
@@ -2185,6 +2197,7 @@ static int hv_pci_probe(struct hv_device *hdev,
hbus = kzalloc(sizeof(*hbus), GFP_KERNEL);
if (!hbus)
return -ENOMEM;
+ hbus->state = hv_pcibus_init;
/*
* The PCI bus "domain" is what is called "segment" in ACPI and
@@ -2348,6 +2361,7 @@ static int hv_pci_remove(struct hv_device *hdev)
pci_stop_root_bus(hbus->pci_bus);
pci_remove_root_bus(hbus->pci_bus);
pci_unlock_rescan_remove();
+ hbus->state = hv_pcibus_removed;
}
hv_pci_bus_exit(hdev);
--
2.7.4
