bnx2x: Protect statistics ramrod and sequence number

Bug fix: Protect statistics ramrod sending code and a statistics counter update
with a spinlock. Otherwise there was a race condition that would allow sending
a statistics ramrods with the same sequence number or with sequence numbers not
in a natural order, which would cause a FW assert.

Signed-off-by: Vladislav Zolotarov <vladz@broadcom.com>
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/bnx2x_main.c b/drivers/net/bnx2x_main.c
index 3dc876ce6e1f3afcb4c1b9fdbefb4fb13ee3395c..b86e47be9967027fdcc7dce64e310b32531fe70e 100644 (file)
--- a/drivers/net/bnx2x_main.c
+++ b/drivers/net/bnx2x_main.c
@@ -3789,6 +3789,8 @@ static void bnx2x_storm_stats_post(struct bnx2x *bp)
                struct eth_query_ramrod_data ramrod_data = {0};
                int i, rc;
 
+               spin_lock_bh(&bp->stats_lock);
+
                ramrod_data.drv_counter = bp->stats_counter++;
                ramrod_data.collect_port = bp->port.pmf ? 1 : 0;
                for_each_queue(bp, i)
@@ -3802,6 +3804,8 @@ static void bnx2x_storm_stats_post(struct bnx2x *bp)
                        bp->spq_left++;
                        bp->stats_pending = 1;
                }
+
+               spin_unlock_bh(&bp->stats_lock);
        }
 }
 
@@ -4367,6 +4371,14 @@ static int bnx2x_storm_stats_update(struct bnx2x *bp)
        struct host_func_stats *fstats = bnx2x_sp(bp, func_stats);
        struct bnx2x_eth_stats *estats = &bp->eth_stats;
        int i;
+       u16 cur_stats_counter;
+
+       /* Make sure we use the value of the counter
+        * used for sending the last stats ramrod.
+        */
+       spin_lock_bh(&bp->stats_lock);
+       cur_stats_counter = bp->stats_counter - 1;
+       spin_unlock_bh(&bp->stats_lock);
 
        memcpy(&(fstats->total_bytes_received_hi),
               &(bnx2x_sp(bp, func_stats_base)->total_bytes_received_hi),
@@ -4394,25 +4406,22 @@ static int bnx2x_storm_stats_update(struct bnx2x *bp)
                u32 diff;
 
                /* are storm stats valid? */
-               if ((u16)(le16_to_cpu(xclient->stats_counter) + 1) !=
-                                                       bp->stats_counter) {
+               if (le16_to_cpu(xclient->stats_counter) != cur_stats_counter) {
                        DP(BNX2X_MSG_STATS, "[%d] stats not updated by xstorm"
                           "  xstorm counter (0x%x) != stats_counter (0x%x)\n",
-                          i, xclient->stats_counter, bp->stats_counter);
+                          i, xclient->stats_counter, cur_stats_counter + 1);
                        return -1;
                }
-               if ((u16)(le16_to_cpu(tclient->stats_counter) + 1) !=
-                                                       bp->stats_counter) {
+               if (le16_to_cpu(tclient->stats_counter) != cur_stats_counter) {
                        DP(BNX2X_MSG_STATS, "[%d] stats not updated by tstorm"
                           "  tstorm counter (0x%x) != stats_counter (0x%x)\n",
-                          i, tclient->stats_counter, bp->stats_counter);
+                          i, tclient->stats_counter, cur_stats_counter + 1);
                        return -2;
                }
-               if ((u16)(le16_to_cpu(uclient->stats_counter) + 1) !=
-                                                       bp->stats_counter) {
+               if (le16_to_cpu(uclient->stats_counter) != cur_stats_counter) {
                        DP(BNX2X_MSG_STATS, "[%d] stats not updated by ustorm"
                           "  ustorm counter (0x%x) != stats_counter (0x%x)\n",
-                          i, uclient->stats_counter, bp->stats_counter);
+                          i, uclient->stats_counter, cur_stats_counter + 1);
                        return -4;
                }