iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

net: dsa: sja1105: serialize sja1105_port_mcast_flood() with other FDB accesses

Browse Source 
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@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Vladimir Oltean 2023-09-08 16:33:51 +03:00 committed by David S. Miller
parent 7cef293b9a
commit ea32690daf
2 changed files with 45 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/net/dsa/sja1105/sja1105.h
View File

@ -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;

56
drivers/net/dsa/sja1105/sja1105_main.c
View File

@ -1798,6 +1798,7 @@ 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) {
@ -1812,12 +1813,16 @@ 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;
@ -1837,6 +1842,20 @@ 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)
{
@ -1899,6 +1918,8 @@ 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];
@ -1912,7 +1933,7 @@ 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)))
@ -1924,14 +1945,16 @@ 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,
@ -2955,7 +2978,9 @@ 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;
@ -2968,7 +2993,8 @@ 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)
@ -2976,10 +3002,13 @@ 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,
@ -3349,6 +3378,7 @@ 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);