This is a note to let you know that I've just added the patch titled
net: stmmac:fix system hang when setting up tag_8021q VLAN for DSA ports
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-stmmac-fix-system-hang-when-setting-up-tag_8021q.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7b61e55914223fba20b5fd516ea041ed7899515d
Author: Yan Wang <rk.code@xxxxxxxxxxx>
Date: Wed Apr 19 22:13:46 2023 +0800
net: stmmac:fix system hang when setting up tag_8021q VLAN for DSA ports
[ 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@xxxxxxxxx>
Signed-off-by: Yan Wang <rk.code@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index a3bd5396c2f87..179f8d196c890 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -6283,6 +6283,10 @@ 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;
@@ -6290,16 +6294,18 @@ 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)
