net: thunderx: Fix OOPs with ethtool --register-dump

The ethtool_ops .get_regs function attempts to read the nonexistent
register NIC_QSET_SQ_0_7_CNM_CHG, which produces a "bus error" type
OOPs.

Fix by not attempting to read, and removing the definition of,
NIC_QSET_SQ_0_7_CNM_CHG.  A zero is written into the register dump to
keep the layout unchanged.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: <stable@vger.kernel.org> # 4.4.x-
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/cavium/thunder/nic_reg.h b/drivers/net/ethernet/cavium/thunder/nic_reg.h
index afb10e3..fab35a5 100644 (file)
--- a/drivers/net/ethernet/cavium/thunder/nic_reg.h
+++ b/drivers/net/ethernet/cavium/thunder/nic_reg.h
@@ -170,7 +170,6 @@
 #define   NIC_QSET_SQ_0_7_DOOR                 (0x010838)
 #define   NIC_QSET_SQ_0_7_STATUS               (0x010840)
 #define   NIC_QSET_SQ_0_7_DEBUG                        (0x010848)
-#define   NIC_QSET_SQ_0_7_CNM_CHG              (0x010860)
 #define   NIC_QSET_SQ_0_7_STAT_0_1             (0x010900)
 
 #define   NIC_QSET_RBDR_0_1_CFG                        (0x010C00)

diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_ethtool.c b/drivers/net/ethernet/cavium/thunder/nicvf_ethtool.c
index d2d8ef2..ad4fddb 100644 (file)
--- a/drivers/net/ethernet/cavium/thunder/nicvf_ethtool.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_ethtool.c
@@ -382,7 +382,10 @@ static void nicvf_get_regs(struct net_device *dev,
                p[i++] = nicvf_queue_reg_read(nic, NIC_QSET_SQ_0_7_DOOR, q);
                p[i++] = nicvf_queue_reg_read(nic, NIC_QSET_SQ_0_7_STATUS, q);
                p[i++] = nicvf_queue_reg_read(nic, NIC_QSET_SQ_0_7_DEBUG, q);
-               p[i++] = nicvf_queue_reg_read(nic, NIC_QSET_SQ_0_7_CNM_CHG, q);
+               /* Padding, was NIC_QSET_SQ_0_7_CNM_CHG, which
+                * produces bus errors when read
+                */
+               p[i++] = 0;
                p[i++] = nicvf_queue_reg_read(nic, NIC_QSET_SQ_0_7_STAT_0_1, q);
                reg_offset = NIC_QSET_SQ_0_7_STAT_0_1 | (1 << 3);
                p[i++] = nicvf_queue_reg_read(nic, reg_offset, q);