tg3: Avoid panic from reserved statblk field access
When RSS is enabled, interrupt vector 0 does not receive any rx traffic.
The rx producer index fields for vector 0's status block should be
considered reserved in this case. This patch changes the code to
respect these reserved fields, which avoids a kernel panic when these
fields take on non-zero values.
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 062ac33..ceeab8e 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -879,8 +879,13 @@
if (sblk->status & SD_STATUS_LINK_CHG)
work_exists = 1;
}
- /* check for RX/TX work to do */
- if (sblk->idx[0].tx_consumer != tnapi->tx_cons ||
+
+ /* check for TX work to do */
+ if (sblk->idx[0].tx_consumer != tnapi->tx_cons)
+ work_exists = 1;
+
+ /* check for RX work to do */
+ if (tnapi->rx_rcb_prod_idx &&
*(tnapi->rx_rcb_prod_idx) != tnapi->rx_rcb_ptr)
work_exists = 1;
@@ -6124,6 +6129,9 @@
return work_done;
}
+ if (!tnapi->rx_rcb_prod_idx)
+ return work_done;
+
/* run RX thread, within the bounds set by NAPI.
* All RX "locking" is done by ensuring outside
* code synchronizes with tg3->napi.poll()
@@ -7567,6 +7575,12 @@
*/
switch (i) {
default:
+ if (tg3_flag(tp, ENABLE_RSS)) {
+ tnapi->rx_rcb_prod_idx = NULL;
+ break;
+ }
+ /* Fall through */
+ case 1:
tnapi->rx_rcb_prod_idx = &sblk->idx[0].rx_producer;
break;
case 2: