From: Yan Wang rk.code@outlook.com
[ Upstream commit 35226750f7ab9d49140d95bc7d38a2a9b0f4fdfc ]
The system hang because of dsa_tag_8021q_port_setup()-> stmmac_vlan_rx_add_vid().
I found in stmmac_drv_probe() that cailing pm_runtime_put() disabled the clock.
First, when the kernel is compiled with CONFIG_PM=y,The stmmac's resume/suspend is active.
Secondly,stmmac as DSA master,the dsa_tag_8021q_port_setup() function will callback stmmac_vlan_rx_add_vid when DSA dirver starts. However, The system is hanged for the stmmac_vlan_rx_add_vid() accesses its registers after stmmac's clock is closed.
I would suggest adding the pm_runtime_resume_and_get() to the stmmac_vlan_rx_add_vid().This guarantees that resuming clock output while in use.
Fixes: b3dcb3127786 ("net: stmmac: correct clocks enabled in stmmac_vlan_rx_kill_vid()") Reviewed-by: Jacob Keller jacob.e.keller@intel.com Signed-off-by: Yan Wang rk.code@outlook.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index d7fcab0570322..f9cd063f1fe30 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -6350,6 +6350,10 @@ static int stmmac_vlan_rx_add_vid(struct net_device *ndev, __be16 proto, u16 vid bool is_double = false; int ret;
+ ret = pm_runtime_resume_and_get(priv->device); + if (ret < 0) + return ret; + if (be16_to_cpu(proto) == ETH_P_8021AD) is_double = true;
@@ -6357,16 +6361,18 @@ static int stmmac_vlan_rx_add_vid(struct net_device *ndev, __be16 proto, u16 vid ret = stmmac_vlan_update(priv, is_double); if (ret) { clear_bit(vid, priv->active_vlans); - return ret; + goto err_pm_put; }
if (priv->hw->num_vlan) { ret = stmmac_add_hw_vlan_rx_fltr(priv, ndev, priv->hw, proto, vid); if (ret) - return ret; + goto err_pm_put; } +err_pm_put: + pm_runtime_put(priv->device);
- return 0; + return ret; }
static int stmmac_vlan_rx_kill_vid(struct net_device *ndev, __be16 proto, u16 vid)