[PATCH net 0/2] bnxt_en: 2 bug fixes.

[PATCH net 0/2] bnxt_en: 2 bug fixes.

[Michael Chan]

Fix crash on ppc64 due to missing memory barrier and restore multicast
after reset.

Michael Chan (2):
  bnxt_en: Need memory barrier when processing the completion ring.
  bnxt_en: Setup multicast properly after resetting device.

 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

-- 
1.8.3.1

[PATCH net 1/2] bnxt_en: Need memory barrier when processing the completion ring.

[Michael Chan]

The code determines if the next ring entry is valid before proceeding
further to read the rest of the entry.  The CPU can re-order and read
the rest of the entry first, possibly reading a stale entry, if DMA
of a new entry happens right after reading it.  This issue can be
readily seen on a ppc64 system, causing it to crash.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 72eb29e..f33ff20 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -1388,6 +1388,10 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
 		if (!TX_CMP_VALID(txcmp, raw_cons))
 			break;
 
+		/* The valid test of the entry must be done first before
+		 * reading any further.
+		 */
+		rmb();
 		if (TX_CMP_TYPE(txcmp) == CMP_TYPE_TX_L2_CMP) {
 			tx_pkts++;
 			/* return full budget so NAPI will complete. */
-- 
1.8.3.1

[PATCH net 2/2] bnxt_en: Setup multicast properly after resetting device.

[Michael Chan]

The multicast/all-multicast internal flags are not properly restored
after device reset.  This could lead to unreliable multicast operations
after an ethtool configuration change for example.

Call bnxt_mc_list_updated() and setup the vnic->mask in bnxt_init_chip()
to fix the issue.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index f33ff20..9d4e8e1 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -4042,9 +4042,11 @@ static int bnxt_alloc_rfs_vnics(struct bnxt *bp)
 }
 
 static int bnxt_cfg_rx_mode(struct bnxt *);
+static bool bnxt_mc_list_updated(struct bnxt *, u32 *);
 
 static int bnxt_init_chip(struct bnxt *bp, bool irq_re_init)
 {
+	struct bnxt_vnic_info *vnic = &bp->vnic_info[0];
 	int rc = 0;
 
 	if (irq_re_init) {
@@ -4100,13 +4102,22 @@ static int bnxt_init_chip(struct bnxt *bp, bool irq_re_init)
 		netdev_err(bp->dev, "HWRM vnic filter failure rc: %x\n", rc);
 		goto err_out;
 	}
-	bp->vnic_info[0].uc_filter_count = 1;
+	vnic->uc_filter_count = 1;
 
-	bp->vnic_info[0].rx_mask = CFA_L2_SET_RX_MASK_REQ_MASK_BCAST;
+	vnic->rx_mask = CFA_L2_SET_RX_MASK_REQ_MASK_BCAST;
 
 	if ((bp->dev->flags & IFF_PROMISC) && BNXT_PF(bp))
-		bp->vnic_info[0].rx_mask |=
-				CFA_L2_SET_RX_MASK_REQ_MASK_PROMISCUOUS;
+		vnic->rx_mask |= CFA_L2_SET_RX_MASK_REQ_MASK_PROMISCUOUS;
+
+	if (bp->dev->flags & IFF_ALLMULTI) {
+		vnic->rx_mask |= CFA_L2_SET_RX_MASK_REQ_MASK_ALL_MCAST;
+		vnic->mc_list_count = 0;
+	} else {
+		u32 mask = 0;
+
+		bnxt_mc_list_updated(bp, &mask);
+		vnic->rx_mask |= mask;
+	}
 
 	rc = bnxt_cfg_rx_mode(bp);
 	if (rc)
-- 
1.8.3.1

Re: [PATCH net 0/2] bnxt_en: 2 bug fixes.

[David Miller]

From: Michael Chan <michael.chan@broadcom.com>
Date: Wed,  4 May 2016 16:56:42 -0400

> Fix crash on ppc64 due to missing memory barrier and restore multicast
> after reset.

Looks good, series applied, thanks.