From 7026789d13178acec9e90f2c4a5cad6c918a8234 Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Mon, 6 Jan 2020 18:01:55 +0000 Subject: [PATCH] mlxsw: spectrum_qdisc: Ignore grafting of invisible FIFO The following patch will change PRIO to replace a removed Qdisc with an invisible FIFO, instead of NOOP. mlxsw will see this replacement due to the graft message that is generated. But because FIFO does not issue its own REPLACE message, when the graft operation takes place, the Qdisc that mlxsw tracks under the indicated band is still the old one. The child handle (0:0) therefore does not match, and mlxsw rejects the graft operation, which leads to an extack message: Warning: Offloading graft operation failed. Fix by ignoring the invisible children in the PRIO graft handler. The DESTROY message of the removed Qdisc is going to follow shortly and handle the removal. Fixes: a8c4f3caf046 ("mlxsw: spectrum: qdiscs: prio: Handle graft command") Signed-off-by: Petr Machata Acked-by: Jiri Pirko Signed-off-by: David S. Miller --- drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c index 68cc6737d45ce..46d43cfd04e9f 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c @@ -651,6 +651,13 @@ mlxsw_sp_qdisc_prio_graft(struct mlxsw_sp_port *mlxsw_sp_port, mlxsw_sp_port->tclass_qdiscs[tclass_num].handle == p->child_handle) return 0; + if (!p->child_handle) { + /* This is an invisible FIFO replacing the original Qdisc. + * Ignore it--the original Qdisc's destroy will follow. + */ + return 0; + } + /* See if the grafted qdisc is already offloaded on any tclass. If so, * unoffload it. */ -- 2.39.5