On 23/07/2024 12:24, Paolo Abeni wrote:

On 7/23/24 10:30, Nikolay Aleksandrov wrote:

...

On 23/07/2024 11:22, Hangbin Liu wrote:

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If the testing kernel doesn't support setting fdb_max_learned or show fdb_n_learned, just skip it. Or we will get errors like

./bridge_fdb_learning_limit.sh: line 218: [: null: integer expression expected ./bridge_fdb_learning_limit.sh: line 225: [: null: integer expression expected

Fixes: 6f84090333bb ("selftests: forwarding: bridge_fdb_learning_limit: Add a new selftest") Signed-off-by: Hangbin Liu liuhangbin@gmail.com

---

.../forwarding/bridge_fdb_learning_limit.sh    | 18 ++++++++++++++++++   1 file changed, 18 insertions(+)

diff --git a/tools/testing/selftests/net/forwarding/bridge_fdb_learning_limit.sh b/tools/testing/selftests/net/forwarding/bridge_fdb_learning_limit.sh index 0760a34b7114..a21b7085da2e 100755 --- a/tools/testing/selftests/net/forwarding/bridge_fdb_learning_limit.sh +++ b/tools/testing/selftests/net/forwarding/bridge_fdb_learning_limit.sh @@ -178,6 +178,22 @@ fdb_del()       check_err $? "Failed to remove a FDB entry of type ${type}"   }   +check_fdb_n_learned_support() +{ +    if ! ip link help bridge 2>&1 | grep -q "fdb_max_learned"; then +        echo "SKIP: iproute2 too old, missing bridge max learned support" +        exit $ksft_skip +    fi

+    ip link add dev br0 type bridge +    local learned=$(fdb_get_n_learned) +    ip link del dev br0 +    if [ "$learned" == "null" ]; then +        echo "SKIP: kernel too old; bridge fdb_n_learned feature not supported." +        exit $ksft_skip +    fi +}

check_accounting_one_type()   {       local type=$1 is_counted=$2 overrides_learned=$3 @@ -274,6 +290,8 @@ check_limit()       done   }   +check_fdb_n_learned_support

trap cleanup EXIT     setup_prepare

Isn't the selftest supposed to be added after the feature was included?

I don't understand why this one is special, we should have the same issue with all new features.

I must admit I was surprised when I learned the fact, but the stable team routinely runs up2date upstream self-tests on top of stable/older kernels:

https://lore.kernel.org/mptcp/ZAHLYvOPEYghRcJ1@kroah.com/

The expected self-test design is to probe the tested feature and skip if not available in the running kernel. The self-test should not break when run on an older kernel not offering such feature.

I understand some (most?) of the self-tests do not cope with the above perfectly, but we can improve ;).

Thanks,

Paolo

Interesting, and unexpected at least for me. :) But okay, I'll keep it in mind when sending/reviewing patches.

Thanks!

For the patch: Acked-by: Nikolay Aleksandrov razor@blackwall.org