From: Petr Machata petrm@mellanox.com
[ Upstream commit 3971a535b839489e4ea31796cc086e6ce616318c ]
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: 32dc5efc6cb4 ("mlxsw: spectrum: qdiscs: prio: Handle graft command") Signed-off-by: Petr Machata petrm@mellanox.com Acked-by: Jiri Pirko jiri@mellanox.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- 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 bdf53cf..720514b 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c @@ -650,6 +650,13 @@ int mlxsw_sp_setup_tc_red(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. */