redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

PCI: hv: Properly handle PCI bus remove 

hv_pci_devices_present() is called in hv_pci_remove() when we remove a PCI
device from the host, e.g., by disabling SR-IOV 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 bus state hv_pcibus_removed, we can avoid this situation.

Reported-by: Xiaofeng Wang <xiaofwan@redhat.com>
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: K. Y. Srinivasan <kys@microsoft.com>
hifive-unleashed-5.1
Long Li 2017-03-23 14:58:10 -07:00 committed by Bjorn Helgaas
parent c1ae3cfa0e
commit d3a78d8bf7
1 changed files with 17 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
drivers/pci/host/pci-hyperv.c
View File

@ -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);