tg3: Add APE register access locking
If the driver resets the chip while the APE is performing a register
access, that register access will never complete and the APE will hang
indefinitely. To prevent this race condition, the driver must acquire
an APE mutex before resetting the chip. The APE will not attempt a
register access until it acquires this lock.
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/tg3.c b/drivers/net/tg3.c
index d2439b8..e3fd74b 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -536,6 +536,7 @@
return 0;
switch (locknum) {
+ case TG3_APE_LOCK_GRC:
case TG3_APE_LOCK_MEM:
break;
default:
@@ -573,6 +574,7 @@
return;
switch (locknum) {
+ case TG3_APE_LOCK_GRC:
case TG3_APE_LOCK_MEM:
break;
default:
@@ -5760,6 +5762,8 @@
tg3_mdio_stop(tp);
+ tg3_ape_lock(tp, TG3_APE_LOCK_GRC);
+
/* No matching tg3_nvram_unlock() after this because
* chip reset below will undo the nvram lock.
*/
@@ -5914,6 +5918,8 @@
tg3_mdio_start(tp);
+ tg3_ape_unlock(tp, TG3_APE_LOCK_GRC);
+
err = tg3_poll_fw(tp);
if (err)
return err;