This is a note to let you know that I've just added the patch titled net: dsa: sja1105: block FDB accesses that are concurrent with a switch reset to the 6.5-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-dsa-sja1105-block-fdb-accesses-that-are-concurre.patch and it can be found in the queue-6.5 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 25916a82f63ae5fdaf412ae056922f7cb4988c33 Author: Vladimir Oltean <vladimir.oltean@xxxxxxx> Date: Fri Sep 8 16:33:52 2023 +0300 net: dsa: sja1105: block FDB accesses that are concurrent with a switch reset [ Upstream commit 86899e9e1e29e854b5f6dcc24ba4f75f792c89aa ] Currently, when we add the first sja1105 port to a bridge with vlan_filtering 1, then we sometimes see this output: sja1105 spi2.2: port 4 failed to read back entry for be:79:b4:9e:9e:96 vid 3088: -ENOENT sja1105 spi2.2: Reset switch and programmed static config. Reason: VLAN filtering sja1105 spi2.2: port 0 failed to add be:79:b4:9e:9e:96 vid 0 to fdb: -2 It is because sja1105_fdb_add() runs from the dsa_owq which is no longer serialized with switch resets since it dropped the rtnl_lock() in the blamed commit. Either performing the FDB accesses before the reset, or after the reset, is equally fine, because sja1105_static_fdb_change() backs up those changes in the static config, but FDB access during reset isn't ok. Make sja1105_static_config_reload() take the fdb_lock to fix that. Fixes: 0faf890fc519 ("net: dsa: drop rtnl_lock from dsa_slave_switchdev_event_work") Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c index 79927191ac623..013976b0af9f1 100644 --- a/drivers/net/dsa/sja1105/sja1105_main.c +++ b/drivers/net/dsa/sja1105/sja1105_main.c @@ -2304,6 +2304,7 @@ int sja1105_static_config_reload(struct sja1105_private *priv, int rc, i; s64 now; + mutex_lock(&priv->fdb_lock); mutex_lock(&priv->mgmt_lock); mac = priv->static_config.tables[BLK_IDX_MAC_CONFIG].entries; @@ -2416,6 +2417,7 @@ int sja1105_static_config_reload(struct sja1105_private *priv, goto out; out: mutex_unlock(&priv->mgmt_lock); + mutex_unlock(&priv->fdb_lock); return rc; }