diff options
Diffstat (limited to 'pkgs/patches-linux-5.15/765-4-net-next-net-dsa-hold-rtnl_mutex-when-calling-dsa_master_-set.patch')
| -rw-r--r-- | pkgs/patches-linux-5.15/765-4-net-next-net-dsa-hold-rtnl_mutex-when-calling-dsa_master_-set.patch | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/pkgs/patches-linux-5.15/765-4-net-next-net-dsa-hold-rtnl_mutex-when-calling-dsa_master_-set.patch b/pkgs/patches-linux-5.15/765-4-net-next-net-dsa-hold-rtnl_mutex-when-calling-dsa_master_-set.patch new file mode 100644 index 0000000..67d4340 --- /dev/null +++ b/pkgs/patches-linux-5.15/765-4-net-next-net-dsa-hold-rtnl_mutex-when-calling-dsa_master_-set.patch @@ -0,0 +1,78 @@ +From c146f9bc195a9dc3ad7fd000a14540e7c9df952d Mon Sep 17 00:00:00 2001 +From: Vladimir Oltean <vladimir.oltean@nxp.com> +Date: Thu, 6 Jan 2022 01:11:15 +0200 +Subject: [PATCH 4/6] net: dsa: hold rtnl_mutex when calling + dsa_master_{setup,teardown} + +DSA needs to simulate master tracking events when a binding is first +with a DSA master established and torn down, in order to give drivers +the simplifying guarantee that ->master_state_change calls are made +only when the master's readiness state to pass traffic changes. +master_state_change() provide a operational bool that DSA driver can use +to understand if DSA master is operational or not. +To avoid races, we need to block the reception of +NETDEV_UP/NETDEV_CHANGE/NETDEV_GOING_DOWN events in the netdev notifier +chain while we are changing the master's dev->dsa_ptr (this changes what +netdev_uses_dsa(dev) reports). + +The dsa_master_setup() and dsa_master_teardown() functions optionally +require the rtnl_mutex to be held, if the tagger needs the master to be +promiscuous, these functions call dev_set_promiscuity(). Move the +rtnl_lock() from that function and make it top-level. + +Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> +Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + net/dsa/dsa2.c | 8 ++++++++ + net/dsa/master.c | 4 ++-- + 2 files changed, 10 insertions(+), 2 deletions(-) + +--- a/net/dsa/dsa2.c ++++ b/net/dsa/dsa2.c +@@ -1034,6 +1034,8 @@ static int dsa_tree_setup_master(struct + struct dsa_port *dp; + int err; + ++ rtnl_lock(); ++ + list_for_each_entry(dp, &dst->ports, list) { + if (dsa_port_is_cpu(dp)) { + err = dsa_master_setup(dp->master, dp); +@@ -1042,6 +1044,8 @@ static int dsa_tree_setup_master(struct + } + } + ++ rtnl_unlock(); ++ + return 0; + } + +@@ -1049,9 +1053,13 @@ static void dsa_tree_teardown_master(str + { + struct dsa_port *dp; + ++ rtnl_lock(); ++ + list_for_each_entry(dp, &dst->ports, list) + if (dsa_port_is_cpu(dp)) + dsa_master_teardown(dp->master); ++ ++ rtnl_unlock(); + } + + static int dsa_tree_setup_lags(struct dsa_switch_tree *dst) +--- a/net/dsa/master.c ++++ b/net/dsa/master.c +@@ -267,9 +267,9 @@ static void dsa_master_set_promiscuity(s + if (!ops->promisc_on_master) + return; + +- rtnl_lock(); ++ ASSERT_RTNL(); ++ + dev_set_promiscuity(dev, inc); +- rtnl_unlock(); + } + + static ssize_t tagging_show(struct device *d, struct device_attribute *attr, |