On 13.10.2017 05:03, Jamal Hadi Salim wrote:
> On 17-10-12 02:12 PM, Nikolay Aleksandrov wrote:
>> On 12/10/17 21:07, Roman Mashak wrote:
>
>>> For example, if you attempt to delete a non-existing vlan on a port,
>>> the current code succeeds and also sends event :
>>>
>>> rtnetlink_rcv_msg
>>> rtnl_bridge_dellink
>>> br_dellink
>>> br_afspec
>>> br_vlan_info
>>>
>>> int br_dellink(..)
>>> {
>>> ...
>>> err = br_afspec()
>>> if (err == 0)
>>> br_ifinfo_notify(RTM_NEWLINK, p);
>>> }
>>>
>>> This is misleading, so a proper errcode has to be produced.
>>>
>>
>
>
>
>> True, but you also change the expected behaviour because now a user can
>> clear all vlans with one request (1 - 4094), and after the change that
>> will fail with a partial delete if some vlan was missing.
>>
>
> The issue is more subtle (per Roman above):
> Try to delete a vlan (that doesnt exist).
> 1) It says "success".
> 2) Worse: Another process listening (bridge monitor?) gets an _event_
> that the vlan has been deleted (when it never existed in the first
> place).
>
>> This has been the behaviour forever and some script might depend on it.
>> Also IMO, and as David also mentioned, doing a partial delete is not
>> good.
>>
>
> I think this is a bug (especially the event part).
>
> cheers,
> jamal
>
Fair enough, but after the patch you get the opposite effect too - you
delete a couple of vlans but you don't generate an event because of an
error in the middle. That at least can be taken care of.
I do agree it's a bug, but there might be scripts that rely on it and
don't check the return value when clearing vlans. They will end up with
a partial clear and wrongly assumed state, so maybe leave the
opportunistic delete but count if anything was actually deleted and send
an event only then ?
That should make everyone happy :-)
