[PATCH 3/3] udevHandleOneDevice: Remove old instance of device on "move"
When a device is "move"-d (this basically means it was renamed),
we add the new device onto our list but keep the old there too.
Fortunately, udev sets this DEVPATH_OLD property which points to
the old device path. We can use it to remove the old instance.
To test this try renaming an interface, for instance:
# ip link set tunl0 name tunl1
# ip link set tunl1 name tunl0
One problem with udev is that it sends old ifname in INTERFACE
property, which creates a problem for us, the property is where
we get the ifname from and use it then to query all kind of info
about the interface. Well, if it is non-existent then we can't
query anything. This happens if ifname rename is suppressed
(net.ifnames=0 on kernel cmd line for instance). Fortunately, we
can use "kernel" source for udev events which has always the
fresh info.
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
src/node_device/node_device_udev.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/src/node_device/node_device_udev.c b/src/node_device/node_device_udev.c
index e9a76a7b01..386f23ef3a 100644
--- a/src/node_device/node_device_udev.c
+++ b/src/node_device/node_device_udev.c
@@ -1507,7 +1507,14 @@ udevHandleOneDevice(struct udev_device *device)
return udevRemoveOneDevice(device);
if (STREQ(action, "move")) {
- /* TODO: implement a way of finding and removing the old device */
+ const char *devpath_old = udevGetDeviceProperty(device,
"DEVPATH_OLD");
+
+ if (devpath_old) {
+ g_autofree char *devpath_old_fixed = g_strdup_printf("/sys%s",
devpath_old);
+
+ udevRemoveOneDeviceSysPath(devpath_old_fixed);
+ }
+
return udevAddOneDevice(device);
}
@@ -1872,7 +1879,7 @@ nodeStateInitialize(bool privileged,
virObjectLock(priv);
- priv->udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
+ priv->udev_monitor = udev_monitor_new_from_netlink(udev, "kernel");
if (!priv->udev_monitor) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("udev_monitor_new_from_netlink returned NULL"));
--
2.25.3