[PATCH net 2/2] qed: Fix qed_ll2_post_rx_buffer_notify_fw() by adding a write memory barrier

[Denis Bolotin]

Make sure chain element is updated before ringing the doorbell.

Signed-off-by: Denis Bolotin <dbolo...@marvell.com>
Signed-off-by: Ariel Elior <ael...@marvell.com>
---
 drivers/net/ethernet/qlogic/qed/qed_ll2.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/qlogic/qed/qed_ll2.c 
b/drivers/net/ethernet/qlogic/qed/qed_ll2.c
index 90afd51..d9237c6 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_ll2.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_ll2.c
@@ -1619,6 +1619,10 @@ static void qed_ll2_post_rx_buffer_notify_fw(struct 
qed_hwfn *p_hwfn,
        cq_prod = qed_chain_get_prod_idx(&p_rx->rcq_chain);
        rx_prod.bd_prod = cpu_to_le16(bd_prod);
        rx_prod.cqe_prod = cpu_to_le16(cq_prod);
+
+       /* Make sure chain element is updated before ringing the doorbell */
+       dma_wmb();
+
        DIRECT_REG_WR(p_rx->set_prod_addr, *((u32 *)&rx_prod));
 }
 
-- 
1.8.3.1