[PATCH 3.13 003/187] bnx2x: fix crash during TSO tunneling

Kamal Mostafa
2014-09-15T23:20:00Z

From: Dmitry Kravkov <Dmitry.Kravkov@qlogic.com>

[ Upstream commit fe26566d8a05151ba1dce75081f6270f73ec4ae1 ]

When TSO packet is transmitted additional BD w/o mapping is used
to describe the packed. The BD needs special handling in tx
completion.

kernel: Call Trace:
kernel: <IRQ> [<ffffffff815e19ba>] dump_stack+0x19/0x1b
kernel: [<ffffffff8105dee1>] warn_slowpath_common+0x61/0x80
kernel: [<ffffffff8105df5c>] warn_slowpath_fmt+0x5c/0x80
kernel: [<ffffffff814a8c0d>] ? find_iova+0x4d/0x90
kernel: [<ffffffff814ab0e2>] intel_unmap_page.part.36+0x142/0x160
kernel: [<ffffffff814ad0e6>] intel_unmap_page+0x26/0x30
kernel: [<ffffffffa01f55d7>] bnx2x_free_tx_pkt+0x157/0x2b0 [bnx2x]
kernel: [<ffffffffa01f8dac>] bnx2x_tx_int+0xac/0x220 [bnx2x]
kernel: [<ffffffff8101a0d9>] ? read_tsc+0x9/0x20
kernel: [<ffffffffa01f8fdb>] bnx2x_poll+0xbb/0x3c0 [bnx2x]
kernel: [<ffffffff814d041a>] net_rx_action+0x15a/0x250
kernel: [<ffffffff81067047>] __do_softirq+0xf7/0x290
kernel: [<ffffffff815f3a5c>] call_softirq+0x1c/0x30
kernel: [<ffffffff81014d25>] do_softirq+0x55/0x90
kernel: [<ffffffff810673e5>] irq_exit+0x115/0x120
kernel: [<ffffffff815f4358>] do_IRQ+0x58/0xf0
kernel: [<ffffffff815e94ad>] common_interrupt+0x6d/0x6d
kernel: <EOI> [<ffffffff810bbff7>] ? clockevents_notify+0x127/0x140
kernel: [<ffffffff814834df>] ? cpuidle_enter_state+0x4f/0xc0
kernel: [<ffffffff81483615>] cpuidle_idle_call+0xc5/0x200
kernel: [<ffffffff8101bc7e>] arch_cpu_idle+0xe/0x30
kernel: [<ffffffff810b4725>] cpu_startup_entry+0xf5/0x290
kernel: [<ffffffff815cfee1>] start_secondary+0x265/0x27b
kernel: ---[ end trace 11aa7726f18d7e80 ]---

Fixes: a848ade408b ("bnx2x: add CSUM and TSO support for encapsulation protocols")
Reported-by: Yulong Pei <ypei@redhat.com>
Cc: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: Dmitry Kravkov <Dmitry.Kravkov@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
drivers/net/ethernet/broadcom/bnx2x/bnx2x.h | 1 +
drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 9 +++++++++
2 files changed, 10 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
index ec61190..a162f82 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
@@ -337,6 +337,7 @@ struct sw_tx_bd {
u8 flags;
/* Set on the first BD descriptor when there is a split BD */
#define BNX2X_TSO_SPLIT_BD (1<<0)
+#define BNX2X_HAS_SECOND_PBD (1<<1)
};

struct sw_rx_page {
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
index db7654a..6089bc4 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
@@ -186,6 +186,12 @@ static u16 bnx2x_free_tx_pkt(struct bnx2x *bp, struct bnx2x_fp_txdata *txdata,
--nbd;
bd_idx = TX_BD(NEXT_TX_IDX(bd_idx));

+ if (tx_buf->flags & BNX2X_HAS_SECOND_PBD) {
+ /* Skip second parse bd... */
+ --nbd;
+ bd_idx = TX_BD(NEXT_TX_IDX(bd_idx));
+ }
+
/* TSO headers+data bds share a common mapping. See bnx2x_tx_split() */
if (tx_buf->flags & BNX2X_TSO_SPLIT_BD) {
tx_data_bd = &txdata->tx_desc_ring[bd_idx].reg_bd;
@@ -3825,6 +3831,9 @@ netdev_tx_t bnx2x_start_xmit(struct sk_buff *skb, struct net_device *dev)
/* set encapsulation flag in start BD */
SET_FLAG(tx_start_bd->general_data,
ETH_TX_START_BD_TUNNEL_EXIST, 1);
+
+ tx_buf->flags |= BNX2X_HAS_SECOND_PBD;
+
nbd++;
} else if (xmit_type & XMIT_CSUM) {
/* Set PBD in checksum offload case w/o encapsulation */
--
1.9.1