From: Ido Schimmel idosch@nvidia.com
[ Upstream commit 35c356924fe3669dfbb1185607ce3b37f70bfa80 ]
Spectrum ASICs have a configurable limit on how deep into the packet they parse. By default, the limit is 96 bytes.
There are several cases where this parsing depth is not enough and there is a need to increase it. For example, timestamping of PTP packets and a FIB multipath hash policy that requires hashing on inner fields. The driver therefore maintains a reference count that reflects the number of consumers that require an increased parsing depth.
During reload_down() the parsing depth reference count does not necessarily drop to zero, but the parsing depth itself is restored to the default during reload_up() when the firmware is reset. It is therefore possible to end up in situations where the driver thinks that the parsing depth was increased (reference count is non-zero), when it is not.
Fix by making sure that all the consumers that increase the parsing depth reference count also decrease it during reload_down(). Specifically, make sure that when the routing code is de-initialized it drops the reference count if it was increased because of a FIB multipath hash policy that requires hashing on inner fields.
Add a warning if the reference count is not zero after the driver was de-initialized and explicitly reset it to zero during initialization for good measures.
Fixes: 2d91f0803b84 ("mlxsw: spectrum: Add infrastructure for parsing configuration") Reported-by: Maksym Yaremchuk maksymy@nvidia.com Signed-off-by: Ido Schimmel idosch@nvidia.com Signed-off-by: Petr Machata petrm@nvidia.com Link: https://lore.kernel.org/r/9c35e1b3e6c1d8f319a2449d14e2b86373f3b3ba.167872752... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlxsw/spectrum.c | 2 ++ .../net/ethernet/mellanox/mlxsw/spectrum_router.c | 14 ++++++++++++++ 2 files changed, 16 insertions(+)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c index f5b2d965d476d..12540feb45088 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c @@ -2937,6 +2937,7 @@ static int mlxsw_sp_netdevice_event(struct notifier_block *unused,
static void mlxsw_sp_parsing_init(struct mlxsw_sp *mlxsw_sp) { + refcount_set(&mlxsw_sp->parsing.parsing_depth_ref, 0); mlxsw_sp->parsing.parsing_depth = MLXSW_SP_DEFAULT_PARSING_DEPTH; mlxsw_sp->parsing.vxlan_udp_dport = MLXSW_SP_DEFAULT_VXLAN_UDP_DPORT; mutex_init(&mlxsw_sp->parsing.lock); @@ -2945,6 +2946,7 @@ static void mlxsw_sp_parsing_init(struct mlxsw_sp *mlxsw_sp) static void mlxsw_sp_parsing_fini(struct mlxsw_sp *mlxsw_sp) { mutex_destroy(&mlxsw_sp->parsing.lock); + WARN_ON_ONCE(refcount_read(&mlxsw_sp->parsing.parsing_depth_ref)); }
struct mlxsw_sp_ipv6_addr_node { diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c index 09e32778b012d..4a73e2fe95ef9 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c @@ -10381,11 +10381,23 @@ static int mlxsw_sp_mp_hash_init(struct mlxsw_sp *mlxsw_sp) old_inc_parsing_depth); return err; } + +static void mlxsw_sp_mp_hash_fini(struct mlxsw_sp *mlxsw_sp) +{ + bool old_inc_parsing_depth = mlxsw_sp->router->inc_parsing_depth; + + mlxsw_sp_mp_hash_parsing_depth_adjust(mlxsw_sp, old_inc_parsing_depth, + false); +} #else static int mlxsw_sp_mp_hash_init(struct mlxsw_sp *mlxsw_sp) { return 0; } + +static void mlxsw_sp_mp_hash_fini(struct mlxsw_sp *mlxsw_sp) +{ +} #endif
static int mlxsw_sp_dscp_init(struct mlxsw_sp *mlxsw_sp) @@ -10615,6 +10627,7 @@ int mlxsw_sp_router_init(struct mlxsw_sp *mlxsw_sp, err_register_inetaddr_notifier: mlxsw_core_flush_owq(); err_dscp_init: + mlxsw_sp_mp_hash_fini(mlxsw_sp); err_mp_hash_init: mlxsw_sp_neigh_fini(mlxsw_sp); err_neigh_init: @@ -10655,6 +10668,7 @@ void mlxsw_sp_router_fini(struct mlxsw_sp *mlxsw_sp) unregister_inet6addr_notifier(&mlxsw_sp->router->inet6addr_nb); unregister_inetaddr_notifier(&mlxsw_sp->router->inetaddr_nb); mlxsw_core_flush_owq(); + mlxsw_sp_mp_hash_fini(mlxsw_sp); mlxsw_sp_neigh_fini(mlxsw_sp); mlxsw_sp_lb_rif_fini(mlxsw_sp); mlxsw_sp_vrs_fini(mlxsw_sp);