On Fri, Nov 03, 2017 at 07:36:41AM -0700, Ashish Varma wrote: > a crash is seen in "netdev_ports_remove" when an interface is deleted and > added > back in the system and when the interface is part of a bridge configuration. > e.g. steps: > create a tap0 interface using "ip tuntap add.." > add the tap0 interface to br0 using "ovs-vsctl add-port.." > delete the tap0 interface from system using "ip tuntap del.." > add the tap0 interface back in system using "ip tuntap add.." > (this changes the ifindex of the interface) > delete tap0 from br0 using "ovs-vsctl del-port.." > > In the function "netdev_ports_insert", two hmap entries were created for > mapping "portnum -> netdev" and "ifindex -> portnum". > When the interface is deleted from the system, the "netdev_ports_remove" > function is not getting called and the old ifindex entry is not getting > cleaned up from the "ifindex_to_port" hmap. > > As part of the fix, added function "dpif_port_remove" which will call > "netdev_ports_remove" in the path where the interface deletion from the system > is detected. > Also, in "netdev_ports_remove", added the code where the > "ifindex_to_port_data" > (ifindex -> portnum map node) is getting freed when the ifindex is not > available any more. (as the interface is already deleted.) > > VMware-BZ: #1975788 > Signed-off-by: Ashish Varma <[email protected]>
Thanks for the patch. It's good to fix a bug and especially to fix a crash. I'm still not entirely certain about the actual need for this hmap, but I guess that this fixes a real problem. This introduces new code in netdev_ports_remove() to handle the new case. The new case duplicates some code that I believe should be possible to avoid duplicating. Can you try to refactor slightly to avoid the code duplication? I see that this writes an expression like: (a == b) && (c == d). Usually, in Open vSwitch, we don't add the extra parentheses unless they are needed or clear up some genuine confusion, so that we would instead write a == b && c == d. Thanks, Ben. _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
