This is a note to let you know that I've just added the patch titled
mlxsw: spectrum_qdisc: Ignore grafting of invisible FIFO
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mlxsw-spectrum_qdisc-ignore-grafting-of-invisible-fifo.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Sat 11 Jan 2020 09:14:34 AM CET
From: Petr Machata <petrm@xxxxxxxxxxxx>
Date: Mon, 6 Jan 2020 18:01:55 +0000
Subject: mlxsw: spectrum_qdisc: Ignore grafting of invisible FIFO
From: Petr Machata <petrm@xxxxxxxxxxxx>
[ 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@xxxxxxxxxxxx>
Acked-by: Jiri Pirko <jiri@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c
@@ -650,6 +650,13 @@ mlxsw_sp_qdisc_prio_graft(struct mlxsw_s
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.
*/
Patches currently in stable-queue which might be from petrm@xxxxxxxxxxxx are
queue-4.19/net-sch_prio-when-ungrafting-replace-with-fifo.patch
queue-4.19/mlxsw-spectrum_qdisc-ignore-grafting-of-invisible-fifo.patch
