[PATCH 1/5] lnst.Devices.SoftDevice: destroy to use _ipr_wrapper

From: Ondrej Lichtner <olichtne(a)redhat.com&gt;

The _ipr_wrapper method implemented in the base Device class can safely
be used for the destroy operation of a SoftDevice. The methods are very
similar so this is just refactoring to reduce code duplication.

Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
---
 lnst/Devices/SoftDevice.py | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/lnst/Devices/SoftDevice.py b/lnst/Devices/SoftDevice.py
index 7a92c24..3373f1d 100644
--- a/lnst/Devices/SoftDevice.py
+++ b/lnst/Devices/SoftDevice.py
@@ -69,14 +69,5 @@ class SoftDevice(Device):
                 self.name, str(e)))
 
     def destroy(self):
-        with pyroute2.IPRoute() as ipr:
-            try:
-                logging.debug("Performing Netlink operation del for device {}
{}".
-                        format(self.ifindex, self.name))
-                ipr.link("del", index=self.ifindex)
-                self._if_manager.rescan_devices()
-            except Exception as e:
-                log_exc_traceback()
-                raise DeviceConfigError("Deleting link {} failed: {}".format(
-                    self.name, str(e)))
+        self._ipr_wrapper("link", "del", index=self.ifindex)
         return True
-- 
2.23.0

[PATCH 2/5] lnst.Slave.NetTestSlave: remove unnecessary rescan_device calls

From: Ondrej Lichtner <olichtne(a)redhat.com&gt;

Since the InterfaceManager.get_device class calls rescan_devices
internally, there's no need to call it externally as well.

Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
---
 lnst/Slave/NetTestSlave.py | 2 --
 1 file changed, 2 deletions(-)

diff --git a/lnst/Slave/NetTestSlave.py b/lnst/Slave/NetTestSlave.py
index 363f053..27f5cce 100644
--- a/lnst/Slave/NetTestSlave.py
+++ b/lnst/Slave/NetTestSlave.py
@@ -241,7 +241,6 @@ class SlaveMethods:
         return setattr(dev, name, value)
 
     def get_devices(self):
-        self._if_manager.rescan_devices()
         devices = self._if_manager.get_devices()
         result = {}
         for device in devices:
@@ -249,7 +248,6 @@ class SlaveMethods:
         return result
 
     def get_device(self, ifindex):
-        self._if_manager.rescan_devices()
         device = self._if_manager.get_device(ifindex)
         if device:
             return device._get_if_data()
-- 
2.23.0

[PATCH 3/5] lnst.Slave.InterfaceManager: redesign rescan_devices

From: Ondrej Lichtner <olichtne(a)redhat.com&gt;

The rescan_devices method historically used the NetUtils.scan_netdevs
method to externally dump the current configuration state of network
devices.

This introduced several race condition issues due to having 2
sockets/communication channels for the same information. The main
problem was that messages received on the main
InterfaceManager._nl_socket should be deprecated when a rescan_devices is
called, however in some situations some messages may already be being
processed and saved in a temporary list when a rescan is called.

This could lead to removing a device during the rescan_devices call,
then adding it back when handling of nl_socket messages resumes, leading
to all sorts of double remove issues.

The redesign to address this issue is to remove the second channel
created by the scan_netdevs method. The direct netlink socket connection
which we use to listen for notifications can also be used to directly
request the dump of the configuration state and add it to the end of the
FIFO message queue in the correct order, resolving any possible race
conditions.

Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
---
 lnst/Slave/InterfaceManager.py | 90 +++++++++-------------------------
 1 file changed, 23 insertions(+), 67 deletions(-)

diff --git a/lnst/Slave/InterfaceManager.py b/lnst/Slave/InterfaceManager.py
index 62f9222..13be2bc 100644
--- a/lnst/Slave/InterfaceManager.py
+++ b/lnst/Slave/InterfaceManager.py
@@ -16,6 +16,7 @@ import re
 import select
 import socket
 import logging
+from collections import deque
 from lnst.Slave.NetConfigCommon import get_option
 from lnst.Common.NetUtils import normalize_hwaddr
 from lnst.Common.NetUtils import scan_netdevs
@@ -25,12 +26,15 @@ from lnst.Common.DeviceError import DeviceNotFound, DeviceConfigError,
DeviceDel
 from lnst.Common.InterfaceManagerError import InterfaceManagerError
 from lnst.Slave.DevlinkManager import DevlinkManager
 from pyroute2 import IPRSocket
+from pyroute2.netlink import NLM_F_REQUEST, NLM_F_DUMP
 from pyroute2.netlink.rtnl import RTMGRP_IPV4_IFADDR
 from pyroute2.netlink.rtnl import RTMGRP_IPV6_IFADDR
 from pyroute2.netlink.rtnl import RTMGRP_LINK
 from pyroute2.netlink.rtnl import RTM_NEWLINK
+from pyroute2.netlink.rtnl import RTM_GETLINK
 from pyroute2.netlink.rtnl import RTM_DELLINK
 from pyroute2.netlink.rtnl import RTM_NEWADDR
+from pyroute2.netlink.rtnl import RTM_GETADDR
 from pyroute2.netlink.rtnl import RTM_DELADDR
 
 NL_GROUPS = RTMGRP_IPV4_IFADDR | RTMGRP_IPV6_IFADDR | RTMGRP_LINK
@@ -44,6 +48,8 @@ class InterfaceManager(object):
         self._nl_socket = IPRSocket()
         self._nl_socket.bind(groups=NL_GROUPS)
 
+        self._msg_queue = deque()
+
         #TODO split DevlinkManager away from the InterfaceManager
         #self._dl_manager = DevlinkManager()
 
@@ -71,78 +77,31 @@ class InterfaceManager(object):
     def get_nl_socket(self):
         return self._nl_socket
 
-    def get_netlink_messages(self):
+    def pull_netlink_messages_into_queue(self):
         try:
-            rl, wl, xl = select.select([self._nl_socket], [], [], 0)
-            try:
-                f = rl[0]
-            except:
-                return []
-            return f.get()
-        except (IndexError, select.error):
-            return []
+            while True:
+                rl, wl, xl = select.select([self._nl_socket], [], [], 0)
+                if not len(rl):
+                    break
+                self._msg_queue.extend(self._nl_socket.get())
         except socket.error:
             self.reconnect_netlink()
             return []
 
     def rescan_devices(self):
-        #since we're rescanning all devices we need to dump all the messages
-        #currently in the Queue of the nl socket - so we don't later update
-        #devices with outdated messages
-        self.get_netlink_messages()
-
-        devices_to_remove = list(self._devices.keys())
-        devs = scan_netdevs()
-        for dev in devs:
-            if dev['index'] not in self._devices:
-                device = self._device_classes["Device"](self)
-                device._init_netlink(dev['netlink_msg'])
-                self._devices[dev['index']] = device
-
-                update_msg = {"type": "dev_created",
-                              "dev_data": device._get_if_data()}
-                self._server_handler.send_data_to_ctl(update_msg)
-
-                device._disable()
-            else:
-               
self._devices[dev['index']]._update_netlink(dev['netlink_msg'])
-                try:
-                    devices_to_remove.remove(dev['index'])
-                except ValueError:
-                    # we may have multiple updates for the same device, it's
-                    # okay not to find the device in devices_to_remove
-                    pass
-
-            self._devices[dev['index']]._clear_ips()
-            for addr_msg in dev['ip_addrs']:
-                self._devices[dev['index']]._update_netlink(addr_msg)
-        for i in devices_to_remove:
-            if i not in self._devices:
-                #TODO
-                #this is a workaround fix for when the device to remove was
-                #already removed indirectly by the previous update loop
-                #the fix works for now but should be refactored at some point
-                continue
-            dev_name = self._devices[i].name
-            logging.debug("Deleting Device with ifindex %d, name %s because "\
-                          "it doesn't exist anymore." % (i, dev_name))
-
-            self._devices[i]._deleted = True
-            del self._devices[i]
-
-            del_msg = {"type": "dev_deleted",
-                       "ifindex": i}
-            self._server_handler.send_data_to_ctl(del_msg)
-
-        # self._dl_manager.rescan_ports()
-        # for device in self._devices.values():
-            # dl_port = self._dl_manager.get_port(device.name)
-            # device._set_devlink(dl_port)
+        self._nl_socket.put(
+            None, RTM_GETLINK, msg_flags=NLM_F_REQUEST | NLM_F_DUMP
+        )
+        self._nl_socket.put(
+            None, RTM_GETADDR, msg_flags=NLM_F_REQUEST | NLM_F_DUMP
+        )
+        self.handle_netlink_msgs()
 
     def handle_netlink_msgs(self):
-        msgs = self.get_netlink_messages()
+        self.pull_netlink_messages_into_queue()
 
-        for msg in msgs:
+        while len(self._msg_queue):
+            msg = self._msg_queue.popleft()
             self._handle_netlink_msg(msg)
 
         # self._dl_manager.rescan_ports()
@@ -153,10 +112,7 @@ class InterfaceManager(object):
     def _handle_netlink_msg(self, msg):
         if msg['header']['type'] in [RTM_NEWLINK, RTM_NEWADDR,
RTM_DELADDR]:
             if msg['index'] in self._devices:
-                try:
-                    self._devices[msg['index']]._update_netlink(msg)
-                except DeviceDeleted:
-                    return
+                self._devices[msg['index']]._update_netlink(msg)
             elif msg['header']['type'] == RTM_NEWLINK:
                 dev = self._device_classes["Device"](self)
                 dev._init_netlink(msg)
-- 
2.23.0

[PATCH 3/5] lnst.Slave.InterfaceManager: redesign rescan_devices

[Jan Tluka]

Fri, Oct 11, 2019 at 04:43:28PM CEST, olichtne(a)redhat.com wrote:
> From: Ondrej Lichtner <olichtne(a)redhat.com&gt;
>
> The rescan_devices method historically used the NetUtils.scan_netdevs
> method to externally dump the current configuration state of network
> devices.
>
> This introduced several race condition issues due to having 2
> sockets/communication channels for the same information. The main
> problem was that messages received on the main
> InterfaceManager._nl_socket should be deprecated when a rescan_devices is
> called, however in some situations some messages may already be being
> processed and saved in a temporary list when a rescan is called.
>
> This could lead to removing a device during the rescan_devices call,
> then adding it back when handling of nl_socket messages resumes, leading
> to all sorts of double remove issues.
>
> The redesign to address this issue is to remove the second channel
> created by the scan_netdevs method. The direct netlink socket connection
> which we use to listen for notifications can also be used to directly
> request the dump of the configuration state and add it to the end of the
> FIFO message queue in the correct order, resolving any possible race
> conditions.
>
> Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
> ---
>  lnst/Slave/InterfaceManager.py | 90 +++++++++-------------------------
>  1 file changed, 23 insertions(+), 67 deletions(-)
>
> diff --git a/lnst/Slave/InterfaceManager.py b/lnst/Slave/InterfaceManager.py
> index 62f9222..13be2bc 100644
> --- a/lnst/Slave/InterfaceManager.py
> +++ b/lnst/Slave/InterfaceManager.py
> @@ -16,6 +16,7 @@ import re
>  import select
>  import socket
>  import logging
> +from collections import deque
>  from lnst.Slave.NetConfigCommon import get_option
>  from lnst.Common.NetUtils import normalize_hwaddr
>  from lnst.Common.NetUtils import scan_netdevs
> @@ -25,12 +26,15 @@ from lnst.Common.DeviceError import DeviceNotFound, DeviceConfigError,
> DeviceDel
>  from lnst.Common.InterfaceManagerError import InterfaceManagerError
>  from lnst.Slave.DevlinkManager import DevlinkManager
>  from pyroute2 import IPRSocket
> +from pyroute2.netlink import NLM_F_REQUEST, NLM_F_DUMP
>  from pyroute2.netlink.rtnl import RTMGRP_IPV4_IFADDR
>  from pyroute2.netlink.rtnl import RTMGRP_IPV6_IFADDR
>  from pyroute2.netlink.rtnl import RTMGRP_LINK
>  from pyroute2.netlink.rtnl import RTM_NEWLINK
> +from pyroute2.netlink.rtnl import RTM_GETLINK
>  from pyroute2.netlink.rtnl import RTM_DELLINK
>  from pyroute2.netlink.rtnl import RTM_NEWADDR
> +from pyroute2.netlink.rtnl import RTM_GETADDR
>  from pyroute2.netlink.rtnl import RTM_DELADDR
>  
>  NL_GROUPS = RTMGRP_IPV4_IFADDR | RTMGRP_IPV6_IFADDR | RTMGRP_LINK
> @@ -44,6 +48,8 @@ class InterfaceManager(object):
>          self._nl_socket = IPRSocket()
>          self._nl_socket.bind(groups=NL_GROUPS)
>  
> +        self._msg_queue = deque()
> +
>          #TODO split DevlinkManager away from the InterfaceManager
>          #self._dl_manager = DevlinkManager()
>  
> @@ -71,78 +77,31 @@ class InterfaceManager(object):
>      def get_nl_socket(self):
>          return self._nl_socket
>  
> -    def get_netlink_messages(self):
> +    def pull_netlink_messages_into_queue(self):
>          try:
> -            rl, wl, xl = select.select([self._nl_socket], [], [], 0)
> -            try:
> -                f = rl[0]
> -            except:
> -                return []
> -            return f.get()
> -        except (IndexError, select.error):
> -            return []
> +            while True:
> +                rl, wl, xl = select.select([self._nl_socket], [], [], 0)
> +                if not len(rl):
> +                    break
> +                self._msg_queue.extend(self._nl_socket.get())
>          except socket.error:
>              self.reconnect_netlink()
>              return []
>  
>      def rescan_devices(self):
> -        #since we're rescanning all devices we need to dump all the messages
> -        #currently in the Queue of the nl socket - so we don't later update
> -        #devices with outdated messages
> -        self.get_netlink_messages()
> -
> -        devices_to_remove = list(self._devices.keys())
> -        devs = scan_netdevs()
> -        for dev in devs:
> -            if dev['index'] not in self._devices:
> -                device = self._device_classes["Device"](self)
> -                device._init_netlink(dev['netlink_msg'])
> -                self._devices[dev['index']] = device
> -
> -                update_msg = {"type": "dev_created",
> -                              "dev_data": device._get_if_data()}
> -                self._server_handler.send_data_to_ctl(update_msg)
> -
> -                device._disable()
> -            else:
> -               
> self._devices[dev['index']]._update_netlink(dev['netlink_msg'])
> -                try:
> -                    devices_to_remove.remove(dev['index'])
> -                except ValueError:
> -                    # we may have multiple updates for the same device, it's
> -                    # okay not to find the device in devices_to_remove
> -                    pass
> -
> -            self._devices[dev['index']]._clear_ips()
> -            for addr_msg in dev['ip_addrs']:
> -                self._devices[dev['index']]._update_netlink(addr_msg)
> -        for i in devices_to_remove:
> -            if i not in self._devices:
> -                #TODO
> -                #this is a workaround fix for when the device to remove was
> -                #already removed indirectly by the previous update loop
> -                #the fix works for now but should be refactored at some point
> -                continue
> -            dev_name = self._devices[i].name
> -            logging.debug("Deleting Device with ifindex %d, name %s because "\
> -                          "it doesn't exist anymore." % (i, dev_name))
> -
> -            self._devices[i]._deleted = True
> -            del self._devices[i]
> -
> -            del_msg = {"type": "dev_deleted",
> -                       "ifindex": i}
> -            self._server_handler.send_data_to_ctl(del_msg)
> -
> -        # self._dl_manager.rescan_ports()
> -        # for device in self._devices.values():
> -            # dl_port = self._dl_manager.get_port(device.name)
> -            # device._set_devlink(dl_port)
> +        self._nl_socket.put(
> +            None, RTM_GETLINK, msg_flags=NLM_F_REQUEST | NLM_F_DUMP
> +        )
> +        self._nl_socket.put(
> +            None, RTM_GETADDR, msg_flags=NLM_F_REQUEST | NLM_F_DUMP
> +        )
> +        self.handle_netlink_msgs() 
Just an idea that I briefly discussed with Ondrej in person.

A user expects that he gets all messages after sending NLM_F_DUMP on
netlink socket in rescan_devices() call. In the code above this is not
guaranteed and may result in race condition (but unlikely to break
something as the messages would be processed elsewhere anyway).

But maybe it's probably worth to wait for the netlink request completion
message in this case.

I'm ok with the current patch, so ACK. We can fix this specific issue later.

-Jan

> 
>     def handle_netlink_msgs(self):
>-        msgs = self.get_netlink_messages()
>+        self.pull_netlink_messages_into_queue()
> 
>-        for msg in msgs:
>+        while len(self._msg_queue):
>+            msg = self._msg_queue.popleft()
>             self._handle_netlink_msg(msg)
> 
>         # self._dl_manager.rescan_ports()
>@@ -153,10 +112,7 @@ class InterfaceManager(object):
>     def _handle_netlink_msg(self, msg):
>         if msg['header']['type'] in [RTM_NEWLINK, RTM_NEWADDR,
RTM_DELADDR]:
>             if msg['index'] in self._devices:
>-                try:
>-                    self._devices[msg['index']]._update_netlink(msg)
>-                except DeviceDeleted:
>-                    return
>+                self._devices[msg['index']]._update_netlink(msg)
>             elif msg['header']['type'] == RTM_NEWLINK:
>                 dev = self._device_classes["Device"](self)
>                 dev._init_netlink(msg)
>-- 
>2.23.0
>_______________________________________________
>LNST-developers mailing list -- lnst-developers(a)lists.fedorahosted.org
>To unsubscribe send an email to lnst-developers-leave(a)lists.fedorahosted.org
>Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/
>List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
>List Archives:
https://lists.fedorahosted.org/archives/list/[e-mail]...

[PATCH 4/5] lnst.Slave.InterfaceManager: remove dependency on Netutils.scan_netdevs

From: Ondrej Lichtner <olichtne(a)redhat.com&gt;

Refactoring the create_device method a little enables us to completely
remove the dependency of the module on scan_netdevs. The method should
now only be used in the legacy NmConfigDevice module that should get
removed soon.

Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
---
 lnst/Slave/InterfaceManager.py | 29 ++++++++++++++++++++---------
 lnst/Slave/NetTestSlave.py     |  2 --
 2 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/lnst/Slave/InterfaceManager.py b/lnst/Slave/InterfaceManager.py
index 13be2bc..cc9f2d5 100644
--- a/lnst/Slave/InterfaceManager.py
+++ b/lnst/Slave/InterfaceManager.py
@@ -19,7 +19,6 @@ import logging
 from collections import deque
 from lnst.Slave.NetConfigCommon import get_option
 from lnst.Common.NetUtils import normalize_hwaddr
-from lnst.Common.NetUtils import scan_netdevs
 from lnst.Common.ExecCmd import exec_cmd
 from lnst.Common.ConnectionHandler import recv_data
 from lnst.Common.DeviceError import DeviceNotFound, DeviceConfigError, DeviceDeleted
@@ -89,13 +88,16 @@ class InterfaceManager(object):
             return []
 
     def rescan_devices(self):
+        self.request_netlink_dump()
+        self.handle_netlink_msgs()
+
+    def request_netlink_dump(self):
         self._nl_socket.put(
             None, RTM_GETLINK, msg_flags=NLM_F_REQUEST | NLM_F_DUMP
         )
         self._nl_socket.put(
             None, RTM_GETADDR, msg_flags=NLM_F_REQUEST | NLM_F_DUMP
         )
-        self.handle_netlink_msgs()
 
     def handle_netlink_msgs(self):
         self.pull_netlink_messages_into_queue()
@@ -196,14 +198,23 @@ class InterfaceManager(object):
         device._create()
         device._bulk_enabled = False
 
-        devs = scan_netdevs()
-        for dev in devs:
-            if dev["name"] == device.name:
-                device._init_netlink(dev['netlink_msg'])
-                self._devices[dev['index']] = device
-                return device
+        self.request_netlink_dump()
+        self.pull_netlink_messages_into_queue()
 
-        return None
+        device_found = False
+        while len(self._msg_queue):
+            msg = self._msg_queue.popleft()
+            if msg.get_attr("IFLA_IFNAME") == device.name:
+                device_found = True
+                device._init_netlink(msg)
+                self._devices[msg['index']] = device
+            else:
+                self._handle_netlink_msg(msg)
+
+        if device_found:
+            return device
+        else:
+            raise DeviceError("Device creation failed")
 
     def replace_dev(self, if_id, dev):
         del self._devices[if_id]
diff --git a/lnst/Slave/NetTestSlave.py b/lnst/Slave/NetTestSlave.py
index 27f5cce..4f5fc9f 100644
--- a/lnst/Slave/NetTestSlave.py
+++ b/lnst/Slave/NetTestSlave.py
@@ -319,8 +319,6 @@ class SlaveMethods:
 
     def create_device(self, clsname, args=[], kwargs={}):
         dev =  self._if_manager.create_device(clsname, args, kwargs)
-        if dev is None:
-            raise Exception("Device creation failed")
         return {"ifindex": dev.ifindex, "name": dev.name}
 
     def start_packet_capture(self, filt):
-- 
2.23.0

[PATCH 4/5] lnst.Slave.InterfaceManager: remove dependency on Netutils.scan_netdevs

[Jan Tluka]

Fri, Oct 11, 2019 at 04:43:29PM CEST, olichtne(a)redhat.com wrote:
> From: Ondrej Lichtner <olichtne(a)redhat.com&gt;
>
> Refactoring the create_device method a little enables us to completely
> remove the dependency of the module on scan_netdevs. The method should
> now only be used in the legacy NmConfigDevice module that should get
> removed soon.
>
> Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
> ---
>  lnst/Slave/InterfaceManager.py | 29 ++++++++++++++++++++---------
>  lnst/Slave/NetTestSlave.py     |  2 --
>  2 files changed, 20 insertions(+), 11 deletions(-)
>
> diff --git a/lnst/Slave/InterfaceManager.py b/lnst/Slave/InterfaceManager.py
> index 13be2bc..cc9f2d5 100644
> --- a/lnst/Slave/InterfaceManager.py
> +++ b/lnst/Slave/InterfaceManager.py
> @@ -19,7 +19,6 @@ import logging
>  from collections import deque
>  from lnst.Slave.NetConfigCommon import get_option
>  from lnst.Common.NetUtils import normalize_hwaddr
> -from lnst.Common.NetUtils import scan_netdevs
>  from lnst.Common.ExecCmd import exec_cmd
>  from lnst.Common.ConnectionHandler import recv_data
>  from lnst.Common.DeviceError import DeviceNotFound, DeviceConfigError, DeviceDeleted
> @@ -89,13 +88,16 @@ class InterfaceManager(object):
>              return []
>  
>      def rescan_devices(self):
> +        self.request_netlink_dump()
> +        self.handle_netlink_msgs()
> +
> +    def request_netlink_dump(self):
>          self._nl_socket.put(
>              None, RTM_GETLINK, msg_flags=NLM_F_REQUEST | NLM_F_DUMP
>          )
>          self._nl_socket.put(
>              None, RTM_GETADDR, msg_flags=NLM_F_REQUEST | NLM_F_DUMP
>          )
> -        self.handle_netlink_msgs()
>  
>      def handle_netlink_msgs(self):
>          self.pull_netlink_messages_into_queue()
> @@ -196,14 +198,23 @@ class InterfaceManager(object):
>          device._create()
>          device._bulk_enabled = False
>  
> -        devs = scan_netdevs()
> -        for dev in devs:
> -            if dev["name"] == device.name:
> -                device._init_netlink(dev['netlink_msg'])
> -                self._devices[dev['index']] = device
> -                return device
> +        self.request_netlink_dump()
> +        self.pull_netlink_messages_into_queue()
>  
> -        return None
> +        device_found = False
> +        while len(self._msg_queue):
> +            msg = self._msg_queue.popleft()
> +            if msg.get_attr("IFLA_IFNAME") == device.name:
> +                device_found = True
> +                device._init_netlink(msg)
> +                self._devices[msg['index']] = device
> +            else:
> +                self._handle_netlink_msg(msg)
> +
> +        if device_found:
> +            return device
> +        else:
> +            raise DeviceError("Device creation failed")
>  
>      def replace_dev(self, if_id, dev):
>          del self._devices[if_id]
> diff --git a/lnst/Slave/NetTestSlave.py b/lnst/Slave/NetTestSlave.py
> index 27f5cce..4f5fc9f 100644
> --- a/lnst/Slave/NetTestSlave.py
> +++ b/lnst/Slave/NetTestSlave.py
> @@ -319,8 +319,6 @@ class SlaveMethods:
>  
>      def create_device(self, clsname, args=[], kwargs={}):
>          dev =  self._if_manager.create_device(clsname, args, kwargs)
> -        if dev is None:
> -            raise Exception("Device creation failed") 
Just wondering if the change of the exception class matters here. If the
DeviceError is excepted somewhere upper in the stack, I'd keep it.

>         return {"ifindex": dev.ifindex, "name": dev.name}
> 
>     def start_packet_capture(self, filt):
>-- 
>2.23.0
>_______________________________________________
>LNST-developers mailing list -- lnst-developers(a)lists.fedorahosted.org
>To unsubscribe send an email to lnst-developers-leave(a)lists.fedorahosted.org
>Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/
>List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
>List Archives:
https://lists.fedorahosted.org/archives/list/[e-mail]...

[PATCH 4/5] lnst.Slave.InterfaceManager: remove dependency on Netutils.scan_netdevs

[Ondrej Lichtner]

On Mon, Oct 14, 2019 at 01:12:46PM +0200, Jan Tluka wrote:
>  Fri, Oct 11, 2019 at 04:43:29PM CEST, olichtne(a)redhat.com wrote:
>  >From: Ondrej Lichtner <olichtne(a)redhat.com&gt;
>  >     def create_device(self, clsname, args=[], kwargs={}):
>  >         dev =  self._if_manager.create_device(clsname, args, kwargs)
>  >-        if dev is None:
>  >-            raise Exception("Device creation failed")
>  
>  Just wondering if the change of the exception class matters here. If the
>  DeviceError is excepted somewhere upper in the stack, I'd keep it. 
I'd like to refactor the whole lnst to only raise exceptions that
inherit from LnstError with different messages/types to indicate the
problem so that we have an easier time tracking down what is broken/what
is just an error to report to a user.

If there's a generic "except Exception" somewhere higher in the stack
(so on the Controller since this is quite close to the top of the Slave)
then that should probably be treated as a bug and addressed.

-Ondrej

[PATCH 5/5] lnst.Devices.RemoteDevice: fix __repr__ in case device was deleted

From: Ondrej Lichtner <olichtne(a)redhat.com&gt;

This is mostly important for printing DeviceResult objects which can
happen after a recipe execution when the device doesn't exist anymore.
In such a case the name attribute can't be accessed and throws an
exception.

Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
---
 lnst/Devices/RemoteDevice.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lnst/Devices/RemoteDevice.py b/lnst/Devices/RemoteDevice.py
index 652e193..f11fa65 100644
--- a/lnst/Devices/RemoteDevice.py
+++ b/lnst/Devices/RemoteDevice.py
@@ -164,7 +164,7 @@ class RemoteDevice(object):
             for k, v in [
                 ("machine", self._machine.get_id()),
                 ("id", self._id),
-                ("name", self.name),
+                ("name", self.name if not self.deleted else
"<deleted>"),
                 ("ifindex", self.ifindex),
             ]
         ]
-- 
2.23.0

[Ondrej Lichtner]

On Fri, Oct 11, 2019 at 04:43:26PM +0200, olichtne(a)redhat.com wrote:
>  From: Ondrej Lichtner <olichtne(a)redhat.com&gt;
>  
>  The _ipr_wrapper method implemented in the base Device class can safely
>  be used for the destroy operation of a SoftDevice. The methods are very
>  similar so this is just refactoring to reduce code duplication.
>  
>  Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
>  ---
>   lnst/Devices/SoftDevice.py | 11 +----------
>   1 file changed, 1 insertion(+), 10 deletions(-)
>  
>  diff --git a/lnst/Devices/SoftDevice.py b/lnst/Devices/SoftDevice.py
>  index 7a92c24..3373f1d 100644
>  --- a/lnst/Devices/SoftDevice.py
>  +++ b/lnst/Devices/SoftDevice.py
>  @@ -69,14 +69,5 @@ class SoftDevice(Device):
>                   self.name, str(e)))
>   
>       def destroy(self):
>  -        with pyroute2.IPRoute() as ipr:
>  -            try:
>  -                logging.debug("Performing Netlink operation del for device {}
> {}".
>  -                        format(self.ifindex, self.name))
>  -                ipr.link("del", index=self.ifindex)
>  -                self._if_manager.rescan_devices()
>  -            except Exception as e:
>  -                log_exc_traceback()
>  -                raise DeviceConfigError("Deleting link {} failed: {}".format(
>  -                    self.name, str(e)))
>  +        self._ipr_wrapper("link", "del", index=self.ifindex)
>           return True
>  -- 
>  2.23.0
>   
patchset pushed.

-Ondrej