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| author | Vladimir Oltean <vladimir.oltean@nxp.com> | 2024-05-27 18:39:54 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-06-12 12:39:53 +0300 |
| commit | 6239e4cd1fde091d6f0502a4af3ba5153c8a1086 (patch) | |
| tree | 0c12b98aa7882bc272f966aff6cf21ed8c66d3e9 | |
| parent | c115b10e4f952f38b29d3c03d57354a7fbe9aa86 (diff) | |
| download | linux-6239e4cd1fde091d6f0502a4af3ba5153c8a1086.tar.xz | |
net/sched: taprio: make q->picos_per_byte available to fill_sched_entry()
[ Upstream commit e634134180885574d1fe7aa162777ba41e7fcd5b ]
In commit b5b73b26b3ca ("taprio: Fix allowing too small intervals"), a
comparison of user input against length_to_duration(q, ETH_ZLEN) was
introduced, to avoid RCU stalls due to frequent hrtimers.
The implementation of length_to_duration() depends on q->picos_per_byte
being set for the link speed. The blamed commit in the Fixes: tag has
moved this too late, so the checks introduced above are ineffective.
The q->picos_per_byte is zero at parse_taprio_schedule() ->
parse_sched_list() -> parse_sched_entry() -> fill_sched_entry() time.
Move the taprio_set_picos_per_byte() call as one of the first things in
taprio_change(), before the bulk of the netlink attribute parsing is
done. That's because it is needed there.
Add a selftest to make sure the issue doesn't get reintroduced.
Fixes: 09dbdf28f9f9 ("net/sched: taprio: fix calculation of maximum gate durations")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240527153955.553333-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/sched/sch_taprio.c | 4 | ||||
| -rw-r--r-- | tools/testing/selftests/tc-testing/tc-tests/qdiscs/taprio.json | 22 |
2 files changed, 25 insertions, 1 deletions
diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index a0d54b422186..631140c1f6e5 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -1851,6 +1851,9 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, } q->flags = taprio_flags; + /* Needed for length_to_duration() during netlink attribute parsing */ + taprio_set_picos_per_byte(dev, q); + err = taprio_parse_mqprio_opt(dev, mqprio, extack, q->flags); if (err < 0) return err; @@ -1910,7 +1913,6 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, if (err < 0) goto free_sched; - taprio_set_picos_per_byte(dev, q); taprio_update_queue_max_sdu(q, new_admin, stab); if (FULL_OFFLOAD_IS_ENABLED(q->flags)) diff --git a/tools/testing/selftests/tc-testing/tc-tests/qdiscs/taprio.json b/tools/testing/selftests/tc-testing/tc-tests/qdiscs/taprio.json index 12da0a939e3e..8f12f00a4f57 100644 --- a/tools/testing/selftests/tc-testing/tc-tests/qdiscs/taprio.json +++ b/tools/testing/selftests/tc-testing/tc-tests/qdiscs/taprio.json @@ -133,6 +133,28 @@ ] }, { + "id": "6f62", + "name": "Add taprio Qdisc with too short interval", + "category": [ + "qdisc", + "taprio" + ], + "plugins": { + "requires": "nsPlugin" + }, + "setup": [ + "echo \"1 1 8\" > /sys/bus/netdevsim/new_device" + ], + "cmdUnderTest": "$TC qdisc add dev $ETH root handle 1: taprio num_tc 2 queues 1@0 1@1 sched-entry S 01 300 sched-entry S 02 1700 clockid CLOCK_TAI", + "expExitCode": "2", + "verifyCmd": "$TC qdisc show dev $ETH", + "matchPattern": "qdisc taprio 1: root refcnt", + "matchCount": "0", + "teardown": [ + "echo \"1\" > /sys/bus/netdevsim/del_device" + ] + }, + { "id": "3e1e", "name": "Add taprio Qdisc with an invalid cycle-time", "category": [ |