diff options
| author | Björn Töpel <bjorn.topel@intel.com> | 2020-12-11 15:57:12 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2020-12-16 10:51:07 -0800 |
| commit | 64050b5b8706d304ba647591b06e1eddc55e8bd9 (patch) | |
| tree | 371bc1fdaaeb6fe6b187afc334ac954221551a38 /drivers/net/ethernet/intel/i40e/i40e_xsk.c | |
| parent | 8d14768a7972b92c73259f0c9c45b969d85e3a60 (diff) | |
i40e, xsk: clear the status bits for the next_to_use descriptor
On the Rx side, the next_to_use index points to the next item in the
HW ring to be refilled/allocated, and next_to_clean points to the next
item to potentially be processed.
When the HW Rx ring is fully refilled, i.e. no packets has been
processed, the next_to_use will be next_to_clean - 1. When the ring is
fully processed next_to_clean will be equal to next_to_use. The latter
case is where a bug is triggered.
If the next_to_use bits are not cleared, and the "fully processed"
state is entered, a stale descriptor can be processed.
The skb-path correctly clear the status bit for the next_to_use
descriptor, but the AF_XDP zero-copy path did not do that.
This change adds the status bits clearing of the next_to_use
descriptor.
Fixes: 3b4f0b66c2b3 ("i40e, xsk: Migrate to new MEM_TYPE_XSK_BUFF_POOL")
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/net/ethernet/intel/i40e/i40e_xsk.c')
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_xsk.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c index bfa84bfb0488..47eb9c584a12 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c +++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c @@ -220,8 +220,11 @@ bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count) } while (count); no_buffers: - if (rx_ring->next_to_use != ntu) + if (rx_ring->next_to_use != ntu) { + /* clear the status bits for the next_to_use descriptor */ + rx_desc->wb.qword1.status_error_len = 0; i40e_release_rx_desc(rx_ring, ntu); + } return ok; } |