From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jiri Pirko <jiri@resnulli.us>
Subject: Re: broken behaviour of TC filter delete
Date: Fri, 24 Aug 2018 10:17:51 +0200
Message-ID: <20180824081751.GA2931@nanopsycho>
References: <851sao225x.fsf@mojatatu.com>
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Cc: netdev@vger.kernel.org, jiri@mellanox.com,
        Jamal Hadi Salim <jhs@mojatatu.com>
To: Roman Mashak <mrv@mojatatu.com>
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Thu, Aug 23, 2018 at 11:39:22PM CEST, mrv@mojatatu.com wrote:
>
>
>It appears that the following commit changed the behaviour of scenario where a
>filter is deleted twice:
>
>commit f71e0ca4db187af7c44987e9d21e9042c3046070
>Author: Jiri Pirko <jiri@mellanox.com>
>Date:   Mon Jul 23 09:23:05 2018 +0200
>
>    net: sched: Avoid implicit chain 0 creation
>
>
>Steps to reproduce :
>
>1) create dummy device
>   $ ip link add dev dummy0 type dummy
>
>2) create qdisc
>   $ tc qdisc add dev dummy0 ingress
>
>3) create simple u32 filter with action attached
>   $ tc filter add dev dummy0 parent ffff: protocol ip prio 1 u32 match ip src 10.10.10.1/32 action ok
>
>4) list the filter
>   $ tc filter ls dev dummy0 parent ffff:
>
>5) delete the filter with the given protocol and priority
>   $ tc filter del dev dummy0 parent ffff: protocol ip prio 1
>
>6) repeat step 5, this will return -ENOENT ("Error: Filter with specified priority/protocol not found.")
>However, before the change at step 6 we would get -EINVAL (Error: Cannot find specified filter chain.)
>and that makes sense.

Wait, this now returns:
Error: Cannot find specified filter chain.
So you want it to return -EINVAL (Error: Cannot find specified filter chain.) ?
How about for other chains?


>
>The change breaks a number of our internal TC tests.