igb: fix handling of mailbox collisions between PF/VF

This patch changes the handling of collisions between the use of the
PF/VF sides of the mailbox.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 9 deletions

diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
index 16349ba68736..78963a0e128d 100644
--- a/drivers/net/igb/igb_main.c
+++ b/drivers/net/igb/igb_main.c
@@ -4608,8 +4608,14 @@ static void igb_rcv_msg_from_vf(struct igb_adapter *adapter, u32 vf)
 
         retval = igb_read_mbx(hw, msgbuf, E1000_VFMAILBOX_SIZE, vf);
 
-        if (retval)
+        if (retval) {
+                /* if receive failed revoke VF CTS stats and restart init */
                 dev_err(&pdev->dev, "Error receiving message from VF\n");
+                vf_data->flags &= ~IGB_VF_FLAG_CTS;
+                if (!time_after(jiffies, vf_data->last_nack + (2 * HZ)))
+                        return;
+                goto out;
+        }
 
         /* this is a message we already processed, do nothing */
         if (msgbuf[0] & (E1000_VT_MSGTYPE_ACK | E1000_VT_MSGTYPE_NACK))
@@ -4626,12 +4632,10 @@ static void igb_rcv_msg_from_vf(struct igb_adapter *adapter, u32 vf)
         }
 
         if (!(vf_data->flags & IGB_VF_FLAG_CTS)) {
-                msgbuf[0] = E1000_VT_MSGTYPE_NACK;
-                if (time_after(jiffies, vf_data->last_nack + (2 * HZ))) {
-                        igb_write_mbx(hw, msgbuf, 1, vf);
-                        vf_data->last_nack = jiffies;
-                }
-                return;
+                if (!time_after(jiffies, vf_data->last_nack + (2 * HZ)))
+                        return;
+                retval = -1;
+                goto out;
         }
 
         switch ((msgbuf[0] & 0xFFFF)) {
@@ -4656,14 +4660,14 @@ static void igb_rcv_msg_from_vf(struct igb_adapter *adapter, u32 vf)
                 break;
         }
 
+        msgbuf[0] |= E1000_VT_MSGTYPE_CTS;
+out:
         /* notify the VF of the results of what it sent us */
         if (retval)
                 msgbuf[0] |= E1000_VT_MSGTYPE_NACK;
         else
                 msgbuf[0] |= E1000_VT_MSGTYPE_ACK;
 
-        msgbuf[0] |= E1000_VT_MSGTYPE_CTS;
-
         igb_write_mbx(hw, msgbuf, 1, vf);
 }