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| 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 | |
| parent | 9cf88808ad6a0f1e958e00abd9a081295fe6da0c (diff) | |
| download | linux-b3873a5be757b44d51af542a50a6f2a3b6f95284.tar.gz | |
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')
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e.h | 2 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_main.c | 10 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_xsk.c | 4 |
3 files changed, 12 insertions, 4 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h index cb6367334ca7..4833187bd259 100644 --- a/drivers/net/ethernet/intel/i40e/i40e.h +++ b/drivers/net/ethernet/intel/i40e/i40e.h @@ -1152,7 +1152,7 @@ void i40e_set_fec_in_flags(u8 fec_cfg, u32 *flags); static inline bool i40e_enabled_xdp_vsi(struct i40e_vsi *vsi) { - return !!vsi->xdp_prog; + return !!READ_ONCE(vsi->xdp_prog); } int i40e_create_queue_channel(struct i40e_vsi *vsi, struct i40e_channel *ch); 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); diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c index d07e1a890428..f73cd917c44f 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c +++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c @@ -787,8 +787,12 @@ int i40e_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags) { struct i40e_netdev_priv *np = netdev_priv(dev); struct i40e_vsi *vsi = np->vsi; + struct i40e_pf *pf = vsi->back; struct i40e_ring *ring; + if (test_bit(__I40E_CONFIG_BUSY, pf->state)) + return -ENETDOWN; + if (test_bit(__I40E_VSI_DOWN, vsi->state)) return -ENETDOWN; |