Re: [PATCH] net: ethernet: ti: cpsw: fix ASSERT_RTNL() warning during resume

From: Dave Gerlach
Date: Wed Nov 30 2016 - 11:03:56 EST


On 11/29/2016 06:18 PM, Ivan Khoronzhuk wrote:
On Tue, Nov 29, 2016 at 04:27:03PM -0600, Grygorii Strashko wrote:
netif_set_real_num_tx/rx_queues() are required to be called with rtnl_lock
taken, otherwise ASSERT_RTNL() warning will be triggered - which happens
now during System resume from suspend:
cpsw_resume()
|- cpsw_ndo_open()
|- netif_set_real_num_tx/rx_queues()
|- ASSERT_RTNL();

Hence, fix it by surrounding cpsw_ndo_open() by rtnl_lock/unlock() calls.

Cc: Dave Gerlach <d-gerlach@xxxxxx>
Cc: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>
Fixes: commit e05107e6b747 ("net: ethernet: ti: cpsw: add multi queue support")
Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
Reviewed-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>


Tested-by: Dave Gerlach <d-gerlach@xxxxxx>

---
drivers/net/ethernet/ti/cpsw.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index ae1ec6a..fd6c03b 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -2944,6 +2944,8 @@ static int cpsw_resume(struct device *dev)
/* Select default pin state */
pinctrl_pm_select_default_state(dev);

+ /* shut up ASSERT_RTNL() warning in netif_set_real_num_tx/rx_queues */
+ rtnl_lock();
if (cpsw->data.dual_emac) {
int i;

@@ -2955,6 +2957,8 @@ static int cpsw_resume(struct device *dev)
if (netif_running(ndev))
cpsw_ndo_open(ndev);
}
+ rtnl_unlock();
+
return 0;
}
#endif
--
2.10.1