From 30520831f058cd9d75c0f6b360bc5c5ae49b5f27 Mon Sep 17 00:00:00 2001 From: Anjali Singhai Jain Date: Fri, 8 May 2015 15:35:52 -0700 Subject: [PATCH] i40e/i40evf: Fix mixed size frags and linearization This patch fixes a bug where the i40e Tx queue will hang if this skb is passed to the driver. With mixed size fragments while using TSO there was a corner case where we needed to linearize but we were not. This was seen with iSCSI traffic and could be reproduced with a frag list that looks like this: num_frags = 17, gso_segs = 17, hdr_len = 66, skb_shinfo(skb)->gso_size = 1448 size = 3002, j = 1, frag_size = 2936, num_frags = 17 size = 4268, j = 1, frag_size = 4096, num_frags = 16 size = 5534, j = 1, frag_size = 4096, num_frags = 15 size = 5352, j = 1, frag_size = 4096, num_frags = 14 size = 5170, j = 1, frag_size = 4096, num_frags = 13 size = 3468, j = 1, frag_size = 2576, num_frags = 12 size = 750, j = 1, frag_size = 112, num_frags = 11 size = 862, j = 2, frag_size = 112, num_frags = 10 size = 974, j = 3, frag_size = 112, num_frags = 9 size = 1126, j = 4, frag_size = 152, num_frags = 8 size = 1330, j = 5, frag_size = 204, num_frags = 7 size = 1534, j = 6, frag_size = 204, num_frags = 6 size = 356, j = 1, frag_size = 204, num_frags = 5 size = 560, j = 2, frag_size = 204, num_frags = 4 size = 764, j = 3, frag_size = 204, num_frags = 3 size = 968, j = 4, frag_size = 204, num_frags = 2 size = 1140, j = 5, frag_size = 172, num_frags = 1 result: linearize = 0, j = 6 Change-ID: I79bb1aeab0af255fe2ce28e93672a85d85bf47e8 Signed-off-by: Anjali Singhai Jain Signed-off-by: Jesse Brandeburg Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/i40e/i40e_txrx.c | 25 ++++++++----------- drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 25 ++++++++----------- 2 files changed, 20 insertions(+), 30 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c index 4bd3a80aba82..9d95042d5a0f 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c @@ -2410,14 +2410,12 @@ static int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size) * i40e_chk_linearize - Check if there are more than 8 fragments per packet * @skb: send buffer * @tx_flags: collected send information - * @hdr_len: size of the packet header * * Note: Our HW can't scatter-gather more than 8 fragments to build * a packet on the wire and so we need to figure out the cases where we * need to linearize the skb. **/ -static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags, - const u8 hdr_len) +static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags) { struct skb_frag_struct *frag; bool linearize = false; @@ -2429,7 +2427,7 @@ static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags, gso_segs = skb_shinfo(skb)->gso_segs; if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO)) { - u16 j = 1; + u16 j = 0; if (num_frags < (I40E_MAX_BUFFER_TXD)) goto linearize_chk_done; @@ -2440,21 +2438,18 @@ static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags, goto linearize_chk_done; } frag = &skb_shinfo(skb)->frags[0]; - size = hdr_len; /* we might still have more fragments per segment */ do { size += skb_frag_size(frag); frag++; j++; + if ((size >= skb_shinfo(skb)->gso_size) && + (j < I40E_MAX_BUFFER_TXD)) { + size = (size % skb_shinfo(skb)->gso_size); + j = (size) ? 1 : 0; + } if (j == I40E_MAX_BUFFER_TXD) { - if (size < skb_shinfo(skb)->gso_size) { - linearize = true; - break; - } - j = 1; - size -= skb_shinfo(skb)->gso_size; - if (size) - j++; - size += hdr_len; + linearize = true; + break; } num_frags--; } while (num_frags); @@ -2724,7 +2719,7 @@ static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb, if (tsyn) tx_flags |= I40E_TX_FLAGS_TSYN; - if (i40e_chk_linearize(skb, tx_flags, hdr_len)) + if (i40e_chk_linearize(skb, tx_flags)) if (skb_linearize(skb)) goto out_drop; diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c index b077e02a0cc7..458fbb421090 100644 --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c @@ -1619,14 +1619,12 @@ static void i40e_create_tx_ctx(struct i40e_ring *tx_ring, * i40e_chk_linearize - Check if there are more than 8 fragments per packet * @skb: send buffer * @tx_flags: collected send information - * @hdr_len: size of the packet header * * Note: Our HW can't scatter-gather more than 8 fragments to build * a packet on the wire and so we need to figure out the cases where we * need to linearize the skb. **/ -static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags, - const u8 hdr_len) +static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags) { struct skb_frag_struct *frag; bool linearize = false; @@ -1638,7 +1636,7 @@ static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags, gso_segs = skb_shinfo(skb)->gso_segs; if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO)) { - u16 j = 1; + u16 j = 0; if (num_frags < (I40E_MAX_BUFFER_TXD)) goto linearize_chk_done; @@ -1649,21 +1647,18 @@ static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags, goto linearize_chk_done; } frag = &skb_shinfo(skb)->frags[0]; - size = hdr_len; /* we might still have more fragments per segment */ do { size += skb_frag_size(frag); frag++; j++; + if ((size >= skb_shinfo(skb)->gso_size) && + (j < I40E_MAX_BUFFER_TXD)) { + size = (size % skb_shinfo(skb)->gso_size); + j = (size) ? 1 : 0; + } if (j == I40E_MAX_BUFFER_TXD) { - if (size < skb_shinfo(skb)->gso_size) { - linearize = true; - break; - } - j = 1; - size -= skb_shinfo(skb)->gso_size; - if (size) - j++; - size += hdr_len; + linearize = true; + break; } num_frags--; } while (num_frags); @@ -1950,7 +1945,7 @@ static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb, else if (tso) tx_flags |= I40E_TX_FLAGS_TSO; - if (i40e_chk_linearize(skb, tx_flags, hdr_len)) + if (i40e_chk_linearize(skb, tx_flags)) if (skb_linearize(skb)) goto out_drop;