6.5-stable review patch. If anyone has any objections, please let me know.
------------------
From: Vladimir Oltean <vladimir.oltean@xxxxxxx>
[ Upstream commit ea32690daf4fa525dc5a4d164bd00ed8c756e1c6 ]
sja1105_fdb_add() runs from the dsa_owq, and sja1105_port_mcast_flood()
runs from switchdev_deferred_process_work(). Prior to the blamed commit,
they used to be indirectly serialized through the rtnl_lock(), which
no longer holds true because dsa_owq dropped that.
So, it is now possible that we traverse the static config BLK_IDX_L2_LOOKUP
elements concurrently compared to when we change them, in
sja1105_static_fdb_change(). That is not ideal, since it might result in
data corruption.
Introduce a mutex which serializes accesses to the hardware FDB and to
the static config elements for the L2 Address Lookup table.
I can't find a good reason to add locking around sja1105_fdb_dump().
I'll add it later if needed.
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>
---
drivers/net/dsa/sja1105/sja1105.h | 2 +
drivers/net/dsa/sja1105/sja1105_main.c | 56 ++++++++++++++++++++------
2 files changed, 45 insertions(+), 13 deletions(-)
diff --git a/drivers/net/dsa/sja1105/sja1105.h b/drivers/net/dsa/sja1105/sja1105.h
index 0617d5ccd3ff1..8c66d3bf61f02 100644
--- a/drivers/net/dsa/sja1105/sja1105.h
+++ b/drivers/net/dsa/sja1105/sja1105.h
@@ -266,6 +266,8 @@ struct sja1105_private {
* the switch doesn't confuse them with one another.
*/
struct mutex mgmt_lock;
+ /* Serializes accesses to the FDB */
+ struct mutex fdb_lock;
/* PTP two-step TX timestamp ID, and its serialization lock */
spinlock_t ts_id_lock;
u8 ts_id;
diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c
index ba65a95b0c372..79927191ac623 100644
--- a/drivers/net/dsa/sja1105/sja1105_main.c
+++ b/drivers/net/dsa/sja1105/sja1105_main.c
@@ -1805,6 +1805,7 @@ static int sja1105_fdb_add(struct dsa_switch *ds, int port,
struct dsa_db db)
{
struct sja1105_private *priv = ds->priv;
+ int rc;
if (!vid) {
switch (db.type) {
@@ -1819,12 +1820,16 @@ static int sja1105_fdb_add(struct dsa_switch *ds, int port,
}
}
- return priv->info->fdb_add_cmd(ds, port, addr, vid);
+ mutex_lock(&priv->fdb_lock);
+ rc = priv->info->fdb_add_cmd(ds, port, addr, vid);
+ mutex_unlock(&priv->fdb_lock);
+
+ return rc;
}
-static int sja1105_fdb_del(struct dsa_switch *ds, int port,
- const unsigned char *addr, u16 vid,
- struct dsa_db db)
+static int __sja1105_fdb_del(struct dsa_switch *ds, int port,
+ const unsigned char *addr, u16 vid,
+ struct dsa_db db)
{
struct sja1105_private *priv = ds->priv;
@@ -1844,6 +1849,20 @@ static int sja1105_fdb_del(struct dsa_switch *ds, int port,
return priv->info->fdb_del_cmd(ds, port, addr, vid);
}
+static int sja1105_fdb_del(struct dsa_switch *ds, int port,
+ const unsigned char *addr, u16 vid,
+ struct dsa_db db)
+{
+ struct sja1105_private *priv = ds->priv;
+ int rc;
+
+ mutex_lock(&priv->fdb_lock);
+ rc = __sja1105_fdb_del(ds, port, addr, vid, db);
+ mutex_unlock(&priv->fdb_lock);
+
+ return rc;
+}
+
static int sja1105_fdb_dump(struct dsa_switch *ds, int port,
dsa_fdb_dump_cb_t *cb, void *data)
{
@@ -1906,6 +1925,8 @@ static void sja1105_fast_age(struct dsa_switch *ds, int port)
};
int i;
+ mutex_lock(&priv->fdb_lock);
+
for (i = 0; i < SJA1105_MAX_L2_LOOKUP_COUNT; i++) {
struct sja1105_l2_lookup_entry l2_lookup = {0};
u8 macaddr[ETH_ALEN];
@@ -1919,7 +1940,7 @@ static void sja1105_fast_age(struct dsa_switch *ds, int port)
if (rc) {
dev_err(ds->dev, "Failed to read FDB: %pe\n",
ERR_PTR(rc));
- return;
+ break;
}
if (!(l2_lookup.destports & BIT(port)))
@@ -1931,14 +1952,16 @@ static void sja1105_fast_age(struct dsa_switch *ds, int port)
u64_to_ether_addr(l2_lookup.macaddr, macaddr);
- rc = sja1105_fdb_del(ds, port, macaddr, l2_lookup.vlanid, db);
+ rc = __sja1105_fdb_del(ds, port, macaddr, l2_lookup.vlanid, db);
if (rc) {
dev_err(ds->dev,
"Failed to delete FDB entry %pM vid %lld: %pe\n",
macaddr, l2_lookup.vlanid, ERR_PTR(rc));
- return;
+ break;
}
}
+
+ mutex_unlock(&priv->fdb_lock);
}
static int sja1105_mdb_add(struct dsa_switch *ds, int port,
@@ -2962,7 +2985,9 @@ static int sja1105_port_mcast_flood(struct sja1105_private *priv, int to,
{
struct sja1105_l2_lookup_entry *l2_lookup;
struct sja1105_table *table;
- int match;
+ int match, rc;
+
+ mutex_lock(&priv->fdb_lock);
table = &priv->static_config.tables[BLK_IDX_L2_LOOKUP];
l2_lookup = table->entries;
@@ -2975,7 +3000,8 @@ static int sja1105_port_mcast_flood(struct sja1105_private *priv, int to,
if (match == table->entry_count) {
NL_SET_ERR_MSG_MOD(extack,
"Could not find FDB entry for unknown multicast");
- return -ENOSPC;
+ rc = -ENOSPC;
+ goto out;
}
if (flags.val & BR_MCAST_FLOOD)
@@ -2983,10 +3009,13 @@ static int sja1105_port_mcast_flood(struct sja1105_private *priv, int to,
else
l2_lookup[match].destports &= ~BIT(to);
- return sja1105_dynamic_config_write(priv, BLK_IDX_L2_LOOKUP,
- l2_lookup[match].index,
- &l2_lookup[match],
- true);
+ rc = sja1105_dynamic_config_write(priv, BLK_IDX_L2_LOOKUP,
+ l2_lookup[match].index,
+ &l2_lookup[match], true);
+out:
+ mutex_unlock(&priv->fdb_lock);
+
+ return rc;
}
static int sja1105_port_pre_bridge_flags(struct dsa_switch *ds, int port,
@@ -3356,6 +3385,7 @@ static int sja1105_probe(struct spi_device *spi)
mutex_init(&priv->ptp_data.lock);
mutex_init(&priv->dynamic_config_lock);
mutex_init(&priv->mgmt_lock);
+ mutex_init(&priv->fdb_lock);
spin_lock_init(&priv->ts_id_lock);
rc = sja1105_parse_dt(priv);
--
2.40.1
