Commit f9124c68 authored Mar 17, 2022 by Maciej Fijalkowski Committed by Tony Nguyen Apr 05, 2022

ice: synchronize_rcu() when terminating rings



Unfortunately, the ice driver doesn't respect the RCU critical section that
XSK wakeup is surrounded with. To fix this, add synchronize_rcu() calls to
paths that destroy resources that might be in use.

This was addressed in other AF_XDP ZC enabled drivers, for reference see
for example commit b3873a5b ("net/i40e: Fix concurrency issues
between config flow and XSK")

Fixes: efc2214b ("ice: Add support for XDP")
Fixes: 2d4238f5 ("ice: Add support for AF_XDP")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Tested-by: Shwetha Nagaraju <shwetha.nagaraju@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

parent 1158f79f

drivers/net/ethernet/intel/ice/ice.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -671,7 +671,7 @@ static inline struct ice_pf ice_netdev_to_pf(struct net_device netdev)

		static inline bool ice_is_xdp_ena_vsi(struct ice_vsi *vsi)
		{
		return !!vsi->xdp_prog;
		return !!READ_ONCE(vsi->xdp_prog);
		}

		static inline void ice_set_ring_xdp(struct ice_tx_ring *ring)

drivers/net/ethernet/intel/ice/ice_main.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -2758,8 +2758,10 @@ int ice_destroy_xdp_rings(struct ice_vsi *vsi)

		ice_for_each_xdp_txq(vsi, i)
		if (vsi->xdp_rings[i]) {
		if (vsi->xdp_rings[i]->desc)
		if (vsi->xdp_rings[i]->desc) {
		synchronize_rcu();
		ice_free_tx_ring(vsi->xdp_rings[i]);
		}
		kfree_rcu(vsi->xdp_rings[i], rcu);
		vsi->xdp_rings[i] = NULL;
		}

drivers/net/ethernet/intel/ice/ice_xsk.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -41,8 +41,10 @@ static void ice_qp_reset_stats(struct ice_vsi *vsi, u16 q_idx)
		static void ice_qp_clean_rings(struct ice_vsi *vsi, u16 q_idx)
		{
		ice_clean_tx_ring(vsi->tx_rings[q_idx]);
		if (ice_is_xdp_ena_vsi(vsi))
		if (ice_is_xdp_ena_vsi(vsi)) {
		synchronize_rcu();
		ice_clean_tx_ring(vsi->xdp_rings[q_idx]);
		}
		ice_clean_rx_ring(vsi->rx_rings[q_idx]);
		}