diff options
| author | Maxim Mikityanskiy <maximmi@mellanox.com> | 2019-12-17 16:20:45 +0000 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2019-12-19 16:20:49 +0100 |
| commit | b3873a5be757b44d51af542a50a6f2a3b6f95284 (patch) | |
| tree | 5881ff638c61189cea401718fdc953a795f331f4 /drivers/net/ethernet/intel/i40e/i40e_main.c | |
| parent | 9cf88808ad6a0f1e958e00abd9a081295fe6da0c (diff) | |
net/i40e: Fix concurrency issues between config flow and XSK
Use synchronize_rcu to wait until the XSK wakeup function finishes
before destroying the resources it uses:
1. i40e_down already calls synchronize_rcu. On i40e_down either
__I40E_VSI_DOWN or __I40E_CONFIG_BUSY is set. Check the latter in
i40e_xsk_wakeup (the former is already checked there).
2. After switching the XDP program, call synchronize_rcu to let
i40e_xsk_wakeup exit before the XDP program is freed.
3. Changing the number of channels brings the interface down (see
i40e_prep_for_reset and i40e_pf_quiesce_all_vsi).
4. Disabling UMEM sets __I40E_CONFIG_BUSY, too.
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191217162023.16011-4-maximmi@mellanox.com
Diffstat (limited to 'drivers/net/ethernet/intel/i40e/i40e_main.c')
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_main.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index 1ccabeafa44c..2c5af6d4a6b1 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -6823,8 +6823,8 @@ void i40e_down(struct i40e_vsi *vsi) for (i = 0; i < vsi->num_queue_pairs; i++) { i40e_clean_tx_ring(vsi->tx_rings[i]); if (i40e_enabled_xdp_vsi(vsi)) { - /* Make sure that in-progress ndo_xdp_xmit - * calls are completed. + /* Make sure that in-progress ndo_xdp_xmit and + * ndo_xsk_wakeup calls are completed. */ synchronize_rcu(); i40e_clean_tx_ring(vsi->xdp_rings[i]); @@ -12546,8 +12546,12 @@ static int i40e_xdp_setup(struct i40e_vsi *vsi, old_prog = xchg(&vsi->xdp_prog, prog); - if (need_reset) + if (need_reset) { + if (!prog) + /* Wait until ndo_xsk_wakeup completes. */ + synchronize_rcu(); i40e_reset_and_rebuild(pf, true, true); + } for (i = 0; i < vsi->num_queue_pairs; i++) WRITE_ONCE(vsi->rx_rings[i]->xdp_prog, vsi->xdp_prog); |