netpoll: use GFP_ATOMIC in slave_enable_netpoll() and __netpoll_setup()

slave_enable_netpoll() and __netpoll_setup() may be called
with read_lock() held, so should use GFP_ATOMIC to allocate
memory. Eric suggested to pass gfp flags to __netpoll_setup().

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

9 files changed, 32 insertions, 28 deletions

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 6fae5f3ec7f6..8697136e27c0 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1235,12 +1235,12 @@ static inline int slave_enable_netpoll(struct slave *slave)
         struct netpoll *np;
         int err = 0;
 
-        np = kzalloc(sizeof(*np), GFP_KERNEL);
+        np = kzalloc(sizeof(*np), GFP_ATOMIC);
         err = -ENOMEM;
         if (!np)
                 goto out;
 
-        err = __netpoll_setup(np, slave->dev);
+        err = __netpoll_setup(np, slave->dev, GFP_ATOMIC);
         if (err) {
                 kfree(np);
                 goto out;
@@ -1292,7 +1292,7 @@ static void bond_netpoll_cleanup(struct net_device *bond_dev)
         read_unlock(&bond->lock);
 }
 
-static int bond_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
+static int bond_netpoll_setup(struct net_device *dev, struct netpoll_info *ni, gfp_t gfp)
 {
         struct bonding *bond = netdev_priv(dev);
         struct slave *slave;
diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
index 87707ab39430..341b65dbbcd3 100644
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -795,16 +795,17 @@ static void team_port_leave(struct team *team, struct team_port *port)
 }
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
-static int team_port_enable_netpoll(struct team *team, struct team_port *port)
+static int team_port_enable_netpoll(struct team *team, struct team_port *port,
+                                    gfp_t gfp)
 {
         struct netpoll *np;
         int err;
 
-        np = kzalloc(sizeof(*np), GFP_KERNEL);
+        np = kzalloc(sizeof(*np), gfp);
         if (!np)
                 return -ENOMEM;
 
-        err = __netpoll_setup(np, port->dev);
+        err = __netpoll_setup(np, port->dev, gfp);
         if (err) {
                 kfree(np);
                 return err;
@@ -833,7 +834,8 @@ static struct netpoll_info *team_netpoll_info(struct team *team)
 }
 
 #else
-static int team_port_enable_netpoll(struct team *team, struct team_port *port)
+static int team_port_enable_netpoll(struct team *team, struct team_port *port,
+                                    gfp_t gfp)
 {
         return 0;
 }
@@ -913,7 +915,7 @@ static int team_port_add(struct team *team, struct net_device *port_dev)
         }
 
         if (team_netpoll_info(team)) {
-                err = team_port_enable_netpoll(team, port);
+                err = team_port_enable_netpoll(team, port, GFP_KERNEL);
                 if (err) {
                         netdev_err(dev, "Failed to enable netpoll on device %s\n",
                                    portname);
@@ -1443,7 +1445,7 @@ static void team_netpoll_cleanup(struct net_device *dev)
 }
 
 static int team_netpoll_setup(struct net_device *dev,
-                              struct netpoll_info *npifo)
+                              struct netpoll_info *npifo, gfp_t gfp)
 {
         struct team *team = netdev_priv(dev);
         struct team_port *port;
@@ -1451,7 +1453,7 @@ static int team_netpoll_setup(struct net_device *dev,
 
         mutex_lock(&team->lock);
         list_for_each_entry(port, &team->port_list, list) {
-                err = team_port_enable_netpoll(team, port);
+                err = team_port_enable_netpoll(team, port, gfp);
                 if (err) {
                         __team_netpoll_cleanup(team);
                         break;
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index a9db4f33407f..3560d688161e 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -953,7 +953,8 @@ struct net_device_ops {
 #ifdef CONFIG_NET_POLL_CONTROLLER
         void                    (*ndo_poll_controller)(struct net_device *dev);
         int                     (*ndo_netpoll_setup)(struct net_device *dev,
-                                                     struct netpoll_info *info);
+                                                     struct netpoll_info *info,
+                                                     gfp_t gfp);
         void                    (*ndo_netpoll_cleanup)(struct net_device *dev);
 #endif
         int                     (*ndo_set_vf_mac)(struct net_device *dev,
diff --git a/include/linux/netpoll.h b/include/linux/netpoll.h
index 28f5389c924b..bf2d51eec0f3 100644
--- a/include/linux/netpoll.h
+++ b/include/linux/netpoll.h
@@ -43,7 +43,7 @@ struct netpoll_info {
 void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
 void netpoll_print_options(struct netpoll *np);
 int netpoll_parse_options(struct netpoll *np, char *opt);
-int __netpoll_setup(struct netpoll *np, struct net_device *ndev);
+int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp);
 int netpoll_setup(struct netpoll *np);
 int netpoll_trap(void);
 void netpoll_set_trap(int trap);
diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index 73a2a83ee2da..ee4ae0944cef 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -669,19 +669,20 @@ static void vlan_dev_poll_controller(struct net_device *dev)
         return;
 }
 
-static int vlan_dev_netpoll_setup(struct net_device *dev, struct netpoll_info *npinfo)
+static int vlan_dev_netpoll_setup(struct net_device *dev, struct netpoll_info *npinfo,
+                                  gfp_t gfp)
 {
         struct vlan_dev_priv *info = vlan_dev_priv(dev);
         struct net_device *real_dev = info->real_dev;
         struct netpoll *netpoll;
         int err = 0;
 
-        netpoll = kzalloc(sizeof(*netpoll), GFP_KERNEL);
+        netpoll = kzalloc(sizeof(*netpoll), gfp);
         err = -ENOMEM;
         if (!netpoll)
                 goto out;
 
-        err = __netpoll_setup(netpoll, real_dev);
+        err = __netpoll_setup(netpoll, real_dev, gfp);
         if (err) {
                 kfree(netpoll);
                 goto out;
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index 333484537600..ed0e0f9dc788 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -213,7 +213,8 @@ static void br_netpoll_cleanup(struct net_device *dev)
         }
 }
 
-static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
+static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni,
+                            gfp_t gfp)
 {
         struct net_bridge *br = netdev_priv(dev);
         struct net_bridge_port *p, *n;
@@ -222,8 +223,7 @@ static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)