[net-next PATCH 1/6] igb: reconfigure mailbox timeout logic

[Jeff Kirsher <jeffrey.t.kirsher@intel.com>]

From: Alexander Duyck <alexander.h.duyck@intel.com>

This change updates the timeout logic so that it is not possible to have a
sucessful check for message and still return an error if countdown = 0.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Reported-by: Juha Leppanen <juha_motorsportscom@luukku.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---

 drivers/net/igb/e1000_mbx.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/igb/e1000_mbx.c b/drivers/net/igb/e1000_mbx.c
index 840782f..ed9058e 100644
--- a/drivers/net/igb/e1000_mbx.c
+++ b/drivers/net/igb/e1000_mbx.c
@@ -140,13 +140,13 @@ static s32 igb_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	int countdown = mbx->timeout;
 
-	if (!mbx->ops.check_for_msg)
+	if (!countdown || !mbx->ops.check_for_msg)
 		goto out;
 
 	while (mbx->ops.check_for_msg(hw, mbx_id)) {
+		countdown--;
 		if (!countdown)
 			break;
-		countdown--;
 		udelay(mbx->usec_delay);
 	}
 out:
@@ -165,13 +165,13 @@ static s32 igb_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
 	struct e1000_mbx_info *mbx = &hw->mbx;
 	int countdown = mbx->timeout;
 
-	if (!mbx->ops.check_for_ack)
+	if (!countdown || !mbx->ops.check_for_ack)
 		goto out;
 
 	while (mbx->ops.check_for_ack(hw, mbx_id)) {
+		countdown--;
 		if (!countdown)
 			break;
-		countdown--;
 		udelay(mbx->usec_delay);
 	}
 out: