There has been a long lasting issue of improper xdp_rings indexing for
XDP_TX and XDP_REDIRECT actions. Given that currently rx_ring->q_index
is mixed with smp_processor_id(), there could be a situation where Tx
descriptors are produced onto XDP Tx ring, but tail is never bumped -
for example pin a particular queue id to non-matching IRQ line.
Address this problem by ignoring the user ring count setting and always
initialize the xdp_rings array to be of num_possible_cpus() size. Then,
always use the smp_processor_id() as an index to xdp_rings array. This
provides serialization as at given time only a single softirq can run on
a particular CPU.
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx>
---
drivers/net/ethernet/intel/ice/ice_lib.c | 2 +-
drivers/net/ethernet/intel/ice/ice_main.c | 2 +-
drivers/net/ethernet/intel/ice/ice_txrx_lib.c | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
index ff403d6a5156..d76e34515483 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -3221,7 +3221,7 @@ int ice_vsi_rebuild(struct ice_vsi *vsi, bool init_vsi)
ice_vsi_map_rings_to_vectors(vsi);
if (ice_is_xdp_ena_vsi(vsi)) {
- vsi->num_xdp_txq = vsi->alloc_rxq;
+ vsi->num_xdp_txq = num_possible_cpus();
ret = ice_prepare_xdp_rings(vsi, vsi->xdp_prog);
if (ret)
goto err_vectors;
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index 5645b6e95fbe..8dc00a14ef56 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -2694,7 +2694,7 @@ ice_xdp_setup_prog(struct ice_vsi *vsi, struct bpf_prog *prog,
}
if (!ice_is_xdp_ena_vsi(vsi) && prog) {
- vsi->num_xdp_txq = vsi->alloc_rxq;
+ vsi->num_xdp_txq = num_possible_cpus();
xdp_ring_err = ice_prepare_xdp_rings(vsi, prog);
if (xdp_ring_err)
NL_SET_ERR_MSG_MOD(extack, "Setting up XDP Tx resources failed");
diff --git a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c
index d6d71f82142f..bc64610df7cb 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c
@@ -297,7 +297,7 @@ void ice_finalize_xdp_rx(struct ice_rx_ring *rx_ring, unsigned int xdp_res)
if (xdp_res & ICE_XDP_TX) {
struct ice_tx_ring *xdp_ring =
- rx_ring->vsi->xdp_rings[rx_ring->q_index];
+ rx_ring->vsi->xdp_rings[smp_processor_id()];
ice_xdp_ring_update_tail(xdp_ring);
}
--
2.20.1
