diff options
| author |   Alexander Duyck <aduyck@mirantis.com> | 2016-03-30 16:15:37 -0700 |
|---|---|---|
| committer |   Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2016-04-13 19:59:23 -0700 |
| commit | 3f3f7cb875c0f621485644d4fd7453b0d37f00e4 (patch) | |
| tree | 64d4eca1728ae968d25225d983f4b639c2048699 /drivers/net/ethernet/intel/i40e/i40e_txrx.h | |
| parent | net: ethernet: renesas: ravb_main: test clock rate to avoid division by 0 (diff) | |
| download | linux-dev-3f3f7cb875c0f621485644d4fd7453b0d37f00e4.tar.xz linux-dev-3f3f7cb875c0f621485644d4fd7453b0d37f00e4.zip | |
i40e/i40evf: Limit TSO to 7 descriptors for payload instead of 8 per packet
This patch addresses a bug introduced based on my interpretation of the
XL710 datasheet. Specifically section 8.4.1 states that "A single transmit
packet may span up to 8 buffers (up to 8 data descriptors per packet
including both the header and payload buffers)." It then later goes on to
say that each segment for a TSO obeys the previous rule, however it then
refers to TSO header and the segment payload buffers.
I believe the actual limit for fragments with TSO and a skbuff that has
payload data in the header portion of the buffer is actually only 7
fragments as the skb->data portion counts as 2 buffers, one for the TSO
header, and one for a segment payload buffer.
Fixes: 2d37490b82af ("i40e/i40evf: Rewrite logic for 8 descriptor per packet check")
Reported-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Diffstat (limited to 'drivers/net/ethernet/intel/i40e/i40e_txrx.h')
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_txrx.h | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h index cdd5dc00aec5..a9bd70537d65 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h @@ -413,10 +413,14 @@ static inline int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size) **/ static inline bool i40e_chk_linearize(struct sk_buff *skb, int count) { - /* we can only support up to 8 data buffers for a single send */ - if (likely(count <= I40E_MAX_BUFFER_TXD)) + /* Both TSO and single send will work if count is less than 8 */ + if (likely(count < I40E_MAX_BUFFER_TXD)) return false; - return __i40e_chk_linearize(skb); + if (skb_is_gso(skb)) + return __i40e_chk_linearize(skb); + + /* we can support up to 8 data buffers for a single send */ + return count != I40E_MAX_BUFFER_TXD; } #endif /* _I40E_TXRX_H_ */ |