taprio: Fix kernel panic in taprio_destroy
authorVladimir Oltean <olteanv@gmail.com>
Fri, 30 Aug 2019 01:07:21 +0000 (04:07 +0300)
committerDavid S. Miller <davem@davemloft.net>
Sun, 1 Sep 2019 01:45:34 +0000 (18:45 -0700)
commitefb55222d31c8c2af8b4ba42bb56b0b0beedf98e
tree86883eb68e11e1c388b8f418b2f1dc3d30894103
parent5f81d5455589df2f580e634c2e9da55b80e63c30
taprio: Fix kernel panic in taprio_destroy

taprio_init may fail earlier than this line:

list_add(&q->taprio_list, &taprio_list);

i.e. due to the net device not being multi queue.

Attempting to remove q from the global taprio_list when it is not part
of it will result in a kernel panic.

Fix it by matching list_add and list_del better to one another in the
order of operations. This way we can keep the deletion unconditional
and with lower complexity - O(1).

Cc: Leandro Dorileo <leandro.maciel.dorileo@intel.com>
Fixes: 7b9eba7ba0c1 ("net/sched: taprio: fix picos_per_byte miscalculation")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/sched/sch_taprio.c