[net-next 05/14] igb: Add message when malformed packets detected by hw

Jeff Kirsher
2014-07-24T13:14:05Z

From: Carolyn Wyborny <carolyn.wyborny@intel.com>

This patch adds a check and prints the error cause register value when
the hardware detects a malformed packet. This is a very unlikely
scenario but has been seen occasionally, so printing the message to
assist the user.

Signed-off-by: Carolyn Wyborny <carolyn.wyborny@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---
drivers/net/ethernet/intel/igb/e1000_regs.h | 1 +
drivers/net/ethernet/intel/igb/igb_main.c | 25 +++++++++++++++++++++++++
2 files changed, 26 insertions(+)

diff --git a/drivers/net/ethernet/intel/igb/e1000_regs.h b/drivers/net/ethernet/intel/igb/e1000_regs.h
index f5ba4e4..6f0490d 100644
--- a/drivers/net/ethernet/intel/igb/e1000_regs.h
+++ b/drivers/net/ethernet/intel/igb/e1000_regs.h
@@ -355,6 +355,7 @@
#define E1000_UTA 0x0A000 /* Unicast Table Array - RW */
#define E1000_IOVTCL 0x05BBC /* IOV Control Register */
#define E1000_TXSWC 0x05ACC /* Tx Switch Control */
+#define E1000_LVMMC 0x03548 /* Last VM Misbehavior cause */
/* These act per VF so an array friendly macro is used */
#define E1000_P2VMAILBOX(_n) (0x00C00 + (4 * (_n)))
#define E1000_VMBMEM(_n) (0x00800 + (64 * (_n)))
diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index 4d2dc17..bd8de67 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -4167,6 +4167,26 @@ static bool igb_thermal_sensor_event(struct e1000_hw *hw, u32 event)
}

/**
+ * igb_check_lvmmc - check for malformed packets received
+ * and indicated in LVMMC register
+ * @adapter: pointer to adapter
+ **/
+static void igb_check_lvmmc(struct igb_adapter *adapter)
+{
+ struct e1000_hw *hw = &adapter->hw;
+ u32 lvmmc;
+
+ lvmmc = rd32(E1000_LVMMC);
+ if (lvmmc) {
+ if (unlikely(net_ratelimit())) {
+ netdev_warn(adapter->netdev,
+ "malformed Tx packet detected and dropped, LVMMC:0x%08x\n",
+ lvmmc);
+ }
+ }
+}
+
+/**
* igb_watchdog - Timer Call-back
* @data: pointer to adapter cast into an unsigned long
**/
@@ -4361,6 +4381,11 @@ static void igb_watchdog_task(struct work_struct *work)
igb_spoof_check(adapter);
igb_ptp_rx_hang(adapter);

+ /* Check LVMMC register on i350/i354 only */
+ if ((adapter->hw.mac.type == e1000_i350) ||
+ (adapter->hw.mac.type == e1000_i354))
+ igb_check_lvmmc(adapter);
+
/* Reset the timer */
if (!test_bit(__IGB_DOWN, &adapter->state)) {
if (adapter->flags & IGB_FLAG_NEED_LINK_UPDATE)
--
1.9.3