From 4eab6c4e07b7c71522d5818c80d746c603c5d69d Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sat, 9 Nov 2019 13:32:24 +0200 Subject: [PATCH] net: dsa: sja1105: Disallow management xmit during switch reset [ Upstream commit af580ae2dcb250719857b4b7024bd4bb0c2e05fb ] The purpose here is to avoid ptp4l fail due to this condition: timed out while polling for tx timestamp increasing tx_timestamp_timeout may correct this issue, but it is likely caused by a driver bug port 1: send peer delay request failed So either reset the switch before the management frame was sent, or after it was timestamped as well, but not in the middle. The condition may arise either due to a true timeout (i.e. because re-uploading the static config takes time), or due to the TX timestamp actually getting lost due to reset. For the former we can increase tx_timestamp_timeout in userspace, for the latter we need this patch. Locking all traffic during switch reset does not make sense at all, though. Forcing all CPU-originated traffic to potentially block waiting for a sleepable context to send > 800 bytes over SPI is not a good idea. Flows that are autonomously forwarded by the switch will get dropped anyway during switch reset no matter what. So just let all other CPU-originated traffic be dropped as well. Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/dsa/sja1105/sja1105_main.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c index aa14066..4e5a428 100644 --- a/drivers/net/dsa/sja1105/sja1105_main.c +++ b/drivers/net/dsa/sja1105/sja1105_main.c @@ -1389,6 +1389,8 @@ int sja1105_static_config_reload(struct sja1105_private *priv) int speed_mbps[SJA1105_NUM_PORTS]; int rc, i; + mutex_lock(&priv->mgmt_lock); + mac = priv->static_config.tables[BLK_IDX_MAC_CONFIG].entries; /* Back up the dynamic link speed changed by sja1105_adjust_port_config @@ -1420,6 +1422,8 @@ int sja1105_static_config_reload(struct sja1105_private *priv) goto out; } out: + mutex_unlock(&priv->mgmt_lock); + return rc; } -- 2.7.4