diff options
| author |   Björn Töpel <bjorn.topel@intel.com> | 2019-02-14 14:03:02 +0100 |
|---|---|---|
| committer |   Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2019-02-21 11:07:49 -0800 |
| commit | 59eb2a884f5380011179acc4662fc2cc2d850454 (patch) | |
| tree | e2d1a2c7fd0d379dfe6bf09a44e1ab3e7e1f648e /drivers/net/ethernet/intel/i40e/i40e_main.c | |
| parent | ixgbe: fix potential RX buffer starvation for AF_XDP (diff) | |
| download | linux-dev-59eb2a884f5380011179acc4662fc2cc2d850454.tar.xz linux-dev-59eb2a884f5380011179acc4662fc2cc2d850454.zip | |
i40e: fix XDP_REDIRECT/XDP xmit ring cleanup race
When the driver clears the XDP xmit ring due to re-configuration or
teardown, in-progress ndo_xdp_xmit must be taken into consideration.
The ndo_xdp_xmit function is typically called from a NAPI context that
the driver does not control. Therefore, we must be careful not to
clear the XDP ring, while the call is on-going. This patch adds a
synchronize_rcu() to wait for napi(s) (preempt-disable regions and
softirqs), prior clearing the queue. Further, the __I40E_CONFIG_BUSY
flag is checked in the ndo_xdp_xmit implementation to avoid touching
the XDP xmit queue during re-configuration.
Fixes: d9314c474d4f ("i40e: add support for XDP_REDIRECT")
Fixes: 123cecd427b6 ("i40e: added queue pair disable/enable functions")
Reported-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Diffstat (limited to 'drivers/net/ethernet/intel/i40e/i40e_main.c')
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_main.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index 3a0990de81c1..e4ff531db14a 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -6728,8 +6728,13 @@ 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)) + if (i40e_enabled_xdp_vsi(vsi)) { + /* Make sure that in-progress ndo_xdp_xmit + * calls are completed. + */ + synchronize_rcu(); i40e_clean_tx_ring(vsi->xdp_rings[i]); + } i40e_clean_rx_ring(vsi->rx_rings[i]); } @@ -11966,8 +11971,13 @@ static void i40e_queue_pair_reset_stats(struct i40e_vsi *vsi, int queue_pair) static void i40e_queue_pair_clean_rings(struct i40e_vsi *vsi, int queue_pair) { i40e_clean_tx_ring(vsi->tx_rings[queue_pair]); - if (i40e_enabled_xdp_vsi(vsi)) + if (i40e_enabled_xdp_vsi(vsi)) { + /* Make sure that in-progress ndo_xdp_xmit calls are + * completed. + */ + synchronize_rcu(); i40e_clean_tx_ring(vsi->xdp_rings[queue_pair]); + } i40e_clean_rx_ring(vsi->rx_rings[queue_pair]); } |