[patch net] mlxsw: spectrum_router: Do not unconditionally clear route offload indication

[patch net] mlxsw: spectrum_router: Do not unconditionally clear route offload indication

[Jiri Pirko]

From: Ido Schimmel <idosch@mellanox.com>

When mlxsw replaces (or deletes) a route it removes the offload
indication from the replaced route. This is problematic for IPv4 routes,
as the offload indication is stored in the fib_info which is usually
shared between multiple routes.

Instead of unconditionally clearing the offload indication, only clear
it if no other route is using the fib_info.

Fixes: 3984d1a89fe7 ("mlxsw: spectrum_router: Provide offload indication using nexthop flags")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Alexander Petrovskiy <alexpe@mellanox.com>
Tested-by: Alexander Petrovskiy <alexpe@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
---
Dave, please, push to stable. Thanks!
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index dcc6305f7c22..f7948e983637 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -3794,6 +3794,9 @@ mlxsw_sp_fib4_entry_offload_unset(struct mlxsw_sp_fib_entry *fib_entry)
 	struct mlxsw_sp_nexthop_group *nh_grp = fib_entry->nh_group;
 	int i;
 
+	if (!list_is_singular(&nh_grp->fib_list))
+		return;
+
 	for (i = 0; i < nh_grp->count; i++) {
 		struct mlxsw_sp_nexthop *nh = &nh_grp->nexthops[i];
 
-- 
2.14.3

Re: [patch net] mlxsw: spectrum_router: Do not unconditionally clear route offload indication

[David Miller]

From: Jiri Pirko <jiri@resnulli.us>
Date: Sat, 17 Feb 2018 00:30:44 +0100

> From: Ido Schimmel <idosch@mellanox.com>
> 
> When mlxsw replaces (or deletes) a route it removes the offload
> indication from the replaced route. This is problematic for IPv4 routes,
> as the offload indication is stored in the fib_info which is usually
> shared between multiple routes.
> 
> Instead of unconditionally clearing the offload indication, only clear
> it if no other route is using the fib_info.
> 
> Fixes: 3984d1a89fe7 ("mlxsw: spectrum_router: Provide offload indication using nexthop flags")
> Signed-off-by: Ido Schimmel <idosch@mellanox.com>
> Reported-by: Alexander Petrovskiy <alexpe@mellanox.com>
> Tested-by: Alexander Petrovskiy <alexpe@mellanox.com>
> Signed-off-by: Jiri Pirko <jiri@mellanox.com>
> ---
> Dave, please, push to stable. Thanks!

Applied and queued up for -stable, thanks Jiri!