* [PATCH 1/2] net: dsa: RCU-protect dsa_ptr in struct net_device
2024-09-10 13:03 [PATCH 0/2] net: dsa: RCU-protect dsa_ptr in struct net_device A. Sverdlin
@ 2024-09-10 13:03 ` A. Sverdlin
2024-09-10 17:40 ` Florian Fainelli
` (2 more replies)
2024-09-11 2:19 ` [PATCH 0/2] " Jakub Kicinski
1 sibling, 3 replies; 12+ messages in thread
From: A. Sverdlin @ 2024-09-10 13:03 UTC (permalink / raw)
To: netdev
Cc: Alexander Sverdlin, Ar1nç ÜNAL, Daniel Golle,
DENG Qingfang, Sean Wang, Andrew Lunn, Florian Fainelli,
Vladimir Oltean, David S. Miller, Eric Dumazet, Jakub Kicinski,
Paolo Abeni, Matthias Brugger, AngeloGioacchino Del Regno,
Claudiu Manoil, Alexandre Belloni, UNGLinuxDriver,
Broadcom internal kernel review list, Lorenzo Bianconi,
Felix Fietkau, Mark Lee, Roopa Prabhu, Nikolay Aleksandrov,
linux-mediatek, bridge, stable
From: Alexander Sverdlin <alexander.sverdlin@siemens.com>
There are multiple races of zeroing dsa_ptr in struct net_device (on
shutdown/remove) against asynchronous dereferences all over the net
code. Widespread pattern is as follows:
CPU0 CPU1
if (netdev_uses_dsa())
dev->dsa_ptr = NULL;
dev->dsa_ptr->...
One of the possible crashes:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
CPU: 0 PID: 12 Comm: ksoftirqd/0 Tainted: G O 6.1.99+ #1
pc : lan9303_rcv
lr : lan9303_rcv
Call trace:
lan9303_rcv
dsa_switch_rcv
__netif_receive_skb_list_core
netif_receive_skb_list_internal
napi_gro_receive
fec_enet_rx_napi
__napi_poll
net_rx_action
...
RCU-protect dsa_ptr and use rcu_dereference() or rtnl_dereference()
depending on the calling context.
Rename netdev_uses_dsa() into __netdev_uses_dsa_currently()
(assumes ether RCU or RTNL lock held) and netdev_uses_dsa_currently()
variants which better reflect the uselessness of the function's
return value, which becomes outdated right after the call.
Fixes: ee534378f005 ("net: dsa: fix panic when DSA master device unbinds on shutdown")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
---
drivers/net/dsa/mt7530.c | 3 +-
drivers/net/dsa/ocelot/felix.c | 3 +-
drivers/net/dsa/qca/qca8k-8xxx.c | 3 +-
drivers/net/ethernet/broadcom/bcmsysport.c | 8 +-
drivers/net/ethernet/mediatek/airoha_eth.c | 2 +-
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 22 +++--
drivers/net/ethernet/mediatek/mtk_ppe.c | 15 ++-
include/linux/netdevice.h | 2 +-
include/net/dsa.h | 36 +++++--
include/net/dsa_stubs.h | 6 +-
net/bridge/br_input.c | 2 +-
net/core/dev.c | 3 +-
net/core/flow_dissector.c | 19 ++--
net/dsa/conduit.c | 66 ++++++++-----
net/dsa/dsa.c | 19 ++--
net/dsa/port.c | 3 +-
net/dsa/tag.c | 3 +-
net/dsa/tag.h | 19 ++--
net/dsa/tag_8021q.c | 10 +-
net/dsa/tag_brcm.c | 2 +-
net/dsa/tag_dsa.c | 8 +-
net/dsa/tag_qca.c | 10 +-
net/dsa/tag_sja1105.c | 22 +++--
net/dsa/user.c | 104 +++++++++++---------
net/ethernet/eth.c | 2 +-
25 files changed, 240 insertions(+), 152 deletions(-)
diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index ec18e68bf3a8..82d3f1786156 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -20,6 +20,7 @@
#include <linux/reset.h>
#include <linux/gpio/consumer.h>
#include <linux/gpio/driver.h>
+#include <linux/rtnetlink.h>
#include <net/dsa.h>
#include "mt7530.h"
@@ -3092,7 +3093,7 @@ mt753x_conduit_state_change(struct dsa_switch *ds,
const struct net_device *conduit,
bool operational)
{
- struct dsa_port *cpu_dp = conduit->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr);
struct mt7530_priv *priv = ds->priv;
int val = 0;
u8 mask;
diff --git a/drivers/net/dsa/ocelot/felix.c b/drivers/net/dsa/ocelot/felix.c
index 4a705f7333f4..f6bc0ff0c116 100644
--- a/drivers/net/dsa/ocelot/felix.c
+++ b/drivers/net/dsa/ocelot/felix.c
@@ -21,6 +21,7 @@
#include <linux/of_net.h>
#include <linux/pci.h>
#include <linux/of.h>
+#include <linux/rtnetlink.h>
#include <net/pkt_sched.h>
#include <net/dsa.h>
#include "felix.h"
@@ -57,7 +58,7 @@ static int felix_cpu_port_for_conduit(struct dsa_switch *ds,
return lag;
}
- cpu_dp = conduit->dsa_ptr;
+ cpu_dp = rtnl_dereference(conduit->dsa_ptr);
return cpu_dp->index;
}
diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c
index f8d8c70642c4..10b4d7e9be2f 100644
--- a/drivers/net/dsa/qca/qca8k-8xxx.c
+++ b/drivers/net/dsa/qca/qca8k-8xxx.c
@@ -20,6 +20,7 @@
#include <linux/gpio/consumer.h>
#include <linux/etherdevice.h>
#include <linux/dsa/tag_qca.h>
+#include <linux/rtnetlink.h>
#include "qca8k.h"
#include "qca8k_leds.h"
@@ -1754,7 +1755,7 @@ static void
qca8k_conduit_change(struct dsa_switch *ds, const struct net_device *conduit,
bool operational)
{
- struct dsa_port *dp = conduit->dsa_ptr;
+ struct dsa_port *dp = rtnl_dereference(conduit->dsa_ptr);
struct qca8k_priv *priv = ds->priv;
/* Ethernet MIB/MDIO is only supported for CPU port 0 */
diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
index c9faa8540859..bd9bc081346d 100644
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -145,7 +145,7 @@ static void bcm_sysport_set_rx_csum(struct net_device *dev,
* sure we tell the RXCHK hardware to expect a 4-bytes Broadcom
* tag after the Ethernet MAC Source Address.
*/
- if (netdev_uses_dsa(dev))
+ if (__netdev_uses_dsa_currently(dev))
reg |= RXCHK_BRCM_TAG_EN;
else
reg &= ~RXCHK_BRCM_TAG_EN;
@@ -173,7 +173,7 @@ static void bcm_sysport_set_tx_csum(struct net_device *dev,
* checksum to be computed correctly when using VLAN HW acceleration,
* else it has no effect, so it can always be turned on.
*/
- if (netdev_uses_dsa(dev))
+ if (__netdev_uses_dsa_currently(dev))
reg |= tdma_control_bit(priv, SW_BRCM_TAG);
else
reg &= ~tdma_control_bit(priv, SW_BRCM_TAG);
@@ -1950,7 +1950,7 @@ static inline void gib_set_pad_extension(struct bcm_sysport_priv *priv)
reg = gib_readl(priv, GIB_CONTROL);
/* Include Broadcom tag in pad extension and fix up IPG_LENGTH */
- if (netdev_uses_dsa(priv->netdev)) {
+ if (__netdev_uses_dsa_currently(priv->netdev)) {
reg &= ~(GIB_PAD_EXTENSION_MASK << GIB_PAD_EXTENSION_SHIFT);
reg |= ENET_BRCM_TAG_LEN << GIB_PAD_EXTENSION_SHIFT;
}
@@ -2299,7 +2299,7 @@ static u16 bcm_sysport_select_queue(struct net_device *dev, struct sk_buff *skb,
struct bcm_sysport_tx_ring *tx_ring;
unsigned int q, port;
- if (!netdev_uses_dsa(dev))
+ if (!__netdev_uses_dsa_currently(dev))
return netdev_pick_tx(dev, skb, NULL);
/* DSA tagging layer will have configured the correct queue */
diff --git a/drivers/net/ethernet/mediatek/airoha_eth.c b/drivers/net/ethernet/mediatek/airoha_eth.c
index 1c5b85a86df1..f7425d393b22 100644
--- a/drivers/net/ethernet/mediatek/airoha_eth.c
+++ b/drivers/net/ethernet/mediatek/airoha_eth.c
@@ -2255,7 +2255,7 @@ static int airoha_dev_open(struct net_device *dev)
if (err)
return err;
- if (netdev_uses_dsa(dev))
+ if (__netdev_uses_dsa_currently(dev))
airoha_fe_set(eth, REG_GDM_INGRESS_CFG(port->id),
GDM_STAG_EN_MASK);
else
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 16ca427cf4c3..82a828349323 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -24,6 +24,7 @@
#include <linux/pcs/pcs-mtk-lynxi.h>
#include <linux/jhash.h>
#include <linux/bitfield.h>
+#include <linux/rcupdate.h>
#include <net/dsa.h>
#include <net/dst_metadata.h>
#include <net/page_pool/helpers.h>
@@ -1375,7 +1376,8 @@ static void mtk_tx_set_dma_desc_v2(struct net_device *dev, void *txd,
/* tx checksum offload */
if (info->csum)
data |= TX_DMA_CHKSUM_V2;
- if (mtk_is_netsys_v3_or_greater(eth) && netdev_uses_dsa(dev))
+ if (mtk_is_netsys_v3_or_greater(eth) &&
+ __netdev_uses_dsa_currently(dev))
data |= TX_DMA_SPTAG_V3;
}
WRITE_ONCE(desc->txd5, data);
@@ -2183,7 +2185,7 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
* hardware treats the MTK special tag as a VLAN and untags it.
*/
if (mtk_is_netsys_v1(eth) && (trxd.rxd2 & RX_DMA_VTAG) &&
- netdev_uses_dsa(netdev)) {
+ __netdev_uses_dsa_currently(netdev)) {
unsigned int port = RX_DMA_VPID(trxd.rxd3) & GENMASK(2, 0);
if (port < ARRAY_SIZE(eth->dsa_meta) &&
@@ -3304,7 +3306,7 @@ static void mtk_gdm_config(struct mtk_eth *eth, u32 id, u32 config)
val |= config;
- if (eth->netdev[id] && netdev_uses_dsa(eth->netdev[id]))
+ if (eth->netdev[id] && __netdev_uses_dsa_currently(eth->netdev[id]))
val |= MTK_GDMA_SPECIAL_TAG;
mtk_w32(eth, val, MTK_GDMA_FWD_CFG(id));
@@ -3313,12 +3315,16 @@ static void mtk_gdm_config(struct mtk_eth *eth, u32 id, u32 config)
static bool mtk_uses_dsa(struct net_device *dev)
{
+ bool ret = false;
#if IS_ENABLED(CONFIG_NET_DSA)
- return netdev_uses_dsa(dev) &&
- dev->dsa_ptr->tag_ops->proto == DSA_TAG_PROTO_MTK;
-#else
- return false;
+ struct dsa_port *dp;
+
+ rcu_read_lock();
+ dp = rcu_dereference(dev->dsa_ptr);
+ ret = dp && dp->tag_ops->proto == DSA_TAG_PROTO_MTK;
+ rcu_read_unlock();
#endif
+ return ret;
}
static int mtk_device_event(struct notifier_block *n, unsigned long event, void *ptr)
@@ -4482,7 +4488,7 @@ static u16 mtk_select_queue(struct net_device *dev, struct sk_buff *skb,
struct mtk_mac *mac = netdev_priv(dev);
unsigned int queue = 0;
- if (netdev_uses_dsa(dev))
+ if (__netdev_uses_dsa_currently(dev))
queue = skb_get_queue_mapping(skb) + 3;
else
queue = mac->id;
diff --git a/drivers/net/ethernet/mediatek/mtk_ppe.c b/drivers/net/ethernet/mediatek/mtk_ppe.c
index 0acee405a749..0c78ec90d855 100644
--- a/drivers/net/ethernet/mediatek/mtk_ppe.c
+++ b/drivers/net/ethernet/mediatek/mtk_ppe.c
@@ -8,6 +8,7 @@
#include <linux/platform_device.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
+#include <linux/rcupdate.h>
#include <net/dst_metadata.h>
#include <net/dsa.h>
#include "mtk_eth_soc.h"
@@ -785,9 +786,17 @@ void __mtk_ppe_check_skb(struct mtk_ppe *ppe, struct sk_buff *skb, u16 hash)
switch (skb->protocol) {
#if IS_ENABLED(CONFIG_NET_DSA)
case htons(ETH_P_XDSA):
- if (!netdev_uses_dsa(skb->dev) ||
- skb->dev->dsa_ptr->tag_ops->proto != DSA_TAG_PROTO_MTK)
- goto out;
+ {
+ struct dsa_port *dp;
+ bool proto_mtk;
+
+ rcu_read_lock();
+ dp = rcu_dereference(skb->dev->dsa_ptr);
+ proto_mtk = dp && dp->tag_ops->proto == DSA_TAG_PROTO_MTK;
+ rcu_read_unlock();
+ if (!proto_mtk)
+ goto out;
+ }
if (!skb_metadata_dst(skb))
tag += 4;
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 607009150b5f..e645c7eabd42 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2229,7 +2229,7 @@ struct net_device {
struct vlan_info __rcu *vlan_info;
#endif
#if IS_ENABLED(CONFIG_NET_DSA)
- struct dsa_port *dsa_ptr;
+ struct dsa_port __rcu *dsa_ptr;
#endif
#if IS_ENABLED(CONFIG_TIPC)
struct tipc_bearer __rcu *tipc_ptr;
diff --git a/include/net/dsa.h b/include/net/dsa.h
index d7a6c2930277..ab2777611e71 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -19,6 +19,7 @@
#include <linux/phy.h>
#include <linux/platform_data/dsa.h>
#include <linux/phylink.h>
+#include <linux/rcupdate.h>
#include <net/devlink.h>
#include <net/switchdev.h>
@@ -92,8 +93,9 @@ struct dsa_switch;
struct dsa_device_ops {
struct sk_buff *(*xmit)(struct sk_buff *skb, struct net_device *dev);
struct sk_buff *(*rcv)(struct sk_buff *skb, struct net_device *dev);
- void (*flow_dissect)(const struct sk_buff *skb, __be16 *proto,
- int *offset);
+ void (*flow_dissect)(const struct sk_buff *skb,
+ const struct dsa_port *dp,
+ __be16 *proto, int *offset);
int (*connect)(struct dsa_switch *ds);
void (*disconnect)(struct dsa_switch *ds);
unsigned int needed_headroom;
@@ -1334,14 +1336,29 @@ bool dsa_mdb_present_in_other_db(struct dsa_switch *ds, int port,
struct dsa_db db);
/* Keep inline for faster access in hot path */
-static inline bool netdev_uses_dsa(const struct net_device *dev)
+
+/* Must be called under RCU or RTNL lock */
+static inline bool __netdev_uses_dsa_currently(const struct net_device *dev)
{
#if IS_ENABLED(CONFIG_NET_DSA)
- return dev->dsa_ptr && dev->dsa_ptr->rcv;
+ struct dsa_port *dp = rcu_dereference_rtnl(dev->dsa_ptr);
+
+ return dp && dp->rcv;
#endif
return false;
}
+static inline bool netdev_uses_dsa_currently(const struct net_device *dev)
+{
+ bool ret = false;
+#if IS_ENABLED(CONFIG_NET_DSA)
+ rcu_read_lock();
+ ret = __netdev_uses_dsa_currently(dev);
+ rcu_read_unlock();
+#endif
+ return ret;
+}
+
/* All DSA tags that push the EtherType to the right (basically all except tail
* tags, which don't break dissection) can be treated the same from the
* perspective of the flow dissector.
@@ -1355,17 +1372,20 @@ static inline bool netdev_uses_dsa(const struct net_device *dev)
* that, in __be16 shorts).
*
* - proto: the value of the real EtherType.
+ *
+ * Must be called under RCU read lock (because of dp).
*/
static inline void dsa_tag_generic_flow_dissect(const struct sk_buff *skb,
+ const struct dsa_port *dp,
__be16 *proto, int *offset)
{
-#if IS_ENABLED(CONFIG_NET_DSA)
- const struct dsa_device_ops *ops = skb->dev->dsa_ptr->tag_ops;
- int tag_len = ops->needed_headroom;
+ int tag_len;
+ RCU_LOCKDEP_WARN(!rcu_read_lock_any_held(), "no rcu lock held");
+
+ tag_len = dp->tag_ops->needed_headroom;
*offset = tag_len;
*proto = ((__be16 *)skb->data)[(tag_len / 2) - 1];
-#endif
}
void dsa_unregister_switch(struct dsa_switch *ds);
diff --git a/include/net/dsa_stubs.h b/include/net/dsa_stubs.h
index 6f384897f287..ca899305ba36 100644
--- a/include/net/dsa_stubs.h
+++ b/include/net/dsa_stubs.h
@@ -22,9 +22,6 @@ static inline int dsa_conduit_hwtstamp_validate(struct net_device *dev,
const struct kernel_hwtstamp_config *config,
struct netlink_ext_ack *extack)
{
- if (!netdev_uses_dsa(dev))
- return 0;
-
/* rtnl_lock() is a sufficient guarantee, because as long as
* netdev_uses_dsa() returns true, the dsa_core module is still
* registered, and so, dsa_unregister_stubs() couldn't have run.
@@ -33,6 +30,9 @@ static inline int dsa_conduit_hwtstamp_validate(struct net_device *dev,
*/
ASSERT_RTNL();
+ if (!__netdev_uses_dsa_currently(dev))
+ return 0;
+
return dsa_stubs->conduit_hwtstamp_validate(dev, config, extack);
}
diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index ceaa5a89b947..542cfc5678df 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -443,7 +443,7 @@ static rx_handler_result_t br_handle_frame_dummy(struct sk_buff **pskb)
rx_handler_func_t *br_get_rx_handler(const struct net_device *dev)
{
- if (netdev_uses_dsa(dev))
+ if (__netdev_uses_dsa_currently(dev))
return br_handle_frame_dummy;
return br_handle_frame;
diff --git a/net/core/dev.c b/net/core/dev.c
index f66e61407883..9ae1c097cbad 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5568,7 +5568,8 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc,
}
}
- if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) {
+ if (unlikely(skb_vlan_tag_present(skb)) &&
+ !__netdev_uses_dsa_currently(skb->dev)) {
check_vlan_id:
if (skb_vlan_tag_get_id(skb)) {
/* Vlan id is non 0 and vlan_do_receive() above couldn't
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 0e638a37aa09..e1523c609bb7 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -1071,25 +1071,30 @@ bool __skb_flow_dissect(const struct net *net,
nhoff = skb_network_offset(skb);
hlen = skb_headlen(skb);
#if IS_ENABLED(CONFIG_NET_DSA)
- if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) &&
- proto == htons(ETH_P_XDSA))) {
+ if (unlikely(skb->dev && proto == htons(ETH_P_XDSA))) {
struct metadata_dst *md_dst = skb_metadata_dst(skb);
- const struct dsa_device_ops *ops;
+ struct dsa_port *dp;
int offset = 0;
- ops = skb->dev->dsa_ptr->tag_ops;
+ rcu_read_lock();
+
+ dp = rcu_dereference(skb->dev->dsa_ptr);
/* Only DSA header taggers break flow dissection */
- if (ops->needed_headroom &&
+ if (dp && dp->tag_ops->needed_headroom &&
(!md_dst || md_dst->type != METADATA_HW_PORT_MUX)) {
- if (ops->flow_dissect)
- ops->flow_dissect(skb, &proto, &offset);
+ if (dp->tag_ops->flow_dissect)
+ dp->tag_ops->flow_dissect(skb, dp,
+ &proto, &offset);
else
dsa_tag_generic_flow_dissect(skb,
+ dp,
&proto,
&offset);
hlen -= offset;
nhoff += offset;
}
+
+ rcu_read_unlock();
}
#endif
}
diff --git a/net/dsa/conduit.c b/net/dsa/conduit.c
index 3dfdb3cb47dc..967770cdf88f 100644
--- a/net/dsa/conduit.c
+++ b/net/dsa/conduit.c
@@ -9,6 +9,7 @@
#include <linux/ethtool.h>
#include <linux/netdevice.h>
#include <linux/netlink.h>
+#include <linux/rcupdate.h>
#include <net/dsa.h>
#include "conduit.h"
@@ -18,7 +19,7 @@
static int dsa_conduit_get_regs_len(struct net_device *dev)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
struct dsa_switch *ds = cpu_dp->ds;
int port = cpu_dp->index;
@@ -48,7 +49,7 @@ static int dsa_conduit_get_regs_len(struct net_device *dev)
static void dsa_conduit_get_regs(struct net_device *dev,
struct ethtool_regs *regs, void *data)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
struct dsa_switch *ds = cpu_dp->ds;
struct ethtool_drvinfo *cpu_info;
@@ -84,7 +85,7 @@ static void dsa_conduit_get_ethtool_stats(struct net_device *dev,
struct ethtool_stats *stats,
uint64_t *data)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
struct dsa_switch *ds = cpu_dp->ds;
int port = cpu_dp->index;
@@ -103,7 +104,7 @@ static void dsa_conduit_get_ethtool_phy_stats(struct net_device *dev,
struct ethtool_stats *stats,
uint64_t *data)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
struct dsa_switch *ds = cpu_dp->ds;
int port = cpu_dp->index;
@@ -127,7 +128,7 @@ static void dsa_conduit_get_ethtool_phy_stats(struct net_device *dev,
static int dsa_conduit_get_sset_count(struct net_device *dev, int sset)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
struct dsa_switch *ds = cpu_dp->ds;
int count = 0;
@@ -150,7 +151,7 @@ static int dsa_conduit_get_sset_count(struct net_device *dev, int sset)
static void dsa_conduit_get_strings(struct net_device *dev, uint32_t stringset,
uint8_t *data)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
struct dsa_switch *ds = cpu_dp->ds;
int port = cpu_dp->index;
@@ -202,7 +203,7 @@ int __dsa_conduit_hwtstamp_validate(struct net_device *dev,
const struct kernel_hwtstamp_config *config,
struct netlink_ext_ack *extack)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
struct dsa_switch *ds = cpu_dp->ds;
struct dsa_switch_tree *dst;
struct dsa_port *dp;
@@ -222,7 +223,7 @@ int __dsa_conduit_hwtstamp_validate(struct net_device *dev,
static int dsa_conduit_ethtool_setup(struct net_device *dev)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
struct dsa_switch *ds = cpu_dp->ds;
struct ethtool_ops *ops;
@@ -251,7 +252,7 @@ static int dsa_conduit_ethtool_setup(struct net_device *dev)
static void dsa_conduit_ethtool_teardown(struct net_device *dev)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
if (netif_is_lag_master(dev))
return;
@@ -267,13 +268,14 @@ static void dsa_conduit_ethtool_teardown(struct net_device *dev)
*/
static void dsa_conduit_set_promiscuity(struct net_device *dev, int inc)
{
- const struct dsa_device_ops *ops = dev->dsa_ptr->tag_ops;
+ const struct dsa_device_ops *ops;
+
+ ASSERT_RTNL();
+ ops = rtnl_dereference(dev->dsa_ptr)->tag_ops;
if ((dev->priv_flags & IFF_UNICAST_FLT) && !ops->promisc_on_conduit)
return;
- ASSERT_RTNL();
-
dev_set_promiscuity(dev, inc);
}
@@ -281,10 +283,17 @@ static ssize_t tagging_show(struct device *d, struct device_attribute *attr,
char *buf)
{
struct net_device *dev = to_net_dev(d);
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp;
+ int ret = 0;
+
+ rcu_read_lock();
+ cpu_dp = rcu_dereference(dev->dsa_ptr);
+ if (cpu_dp)
+ ret = sysfs_emit(buf, "%s\n",
+ dsa_tag_protocol_to_str(cpu_dp->tag_ops));
+ rcu_read_unlock();
- return sysfs_emit(buf, "%s\n",
- dsa_tag_protocol_to_str(cpu_dp->tag_ops));
+ return ret;
}
static ssize_t tagging_store(struct device *d, struct device_attribute *attr,
@@ -293,7 +302,7 @@ static ssize_t tagging_store(struct device *d, struct device_attribute *attr,
const struct dsa_device_ops *new_tag_ops, *old_tag_ops;
const char *end = strchrnul(buf, '\n'), *name;
struct net_device *dev = to_net_dev(d);
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp;
size_t len = end - buf;
int err;
@@ -305,13 +314,17 @@ static ssize_t tagging_store(struct device *d, struct device_attribute *attr,
if (!name)
return -ENOMEM;
- old_tag_ops = cpu_dp->tag_ops;
new_tag_ops = dsa_tag_driver_get_by_name(name);
kfree(name);
/* Bad tagger name? */
if (IS_ERR(new_tag_ops))
return PTR_ERR(new_tag_ops);
+ if (!rtnl_trylock())
+ return restart_syscall();
+
+ cpu_dp = rtnl_dereference(dev->dsa_ptr);
+ old_tag_ops = cpu_dp->tag_ops;
if (new_tag_ops == old_tag_ops)
/* Drop the temporarily held duplicate reference, since
* the DSA switch tree uses this tagger.
@@ -321,6 +334,7 @@ static ssize_t tagging_store(struct device *d, struct device_attribute *attr,
err = dsa_tree_change_tag_proto(cpu_dp->ds->dst, new_tag_ops,
old_tag_ops);
if (err) {
+ rtnl_unlock();
/* On failure the old tagger is restored, so we don't need the
* driver for the new one.
*/
@@ -331,6 +345,7 @@ static ssize_t tagging_store(struct device *d, struct device_attribute *attr,
/* On success we no longer need the module for the old tagging protocol
*/
out:
+ rtnl_unlock();
dsa_tag_driver_put(old_tag_ops);
return count;
}
@@ -384,13 +399,11 @@ int dsa_conduit_setup(struct net_device *dev, struct dsa_port *cpu_dp)
netdev_warn(dev, "error %d setting MTU to %d to include DSA overhead\n",
ret, mtu);
- /* If we use a tagging format that doesn't have an ethertype
- * field, make sure that all packets from this point on get
- * sent to the tag format's receive function.
+ rcu_assign_pointer(dev->dsa_ptr, cpu_dp);
+ /*
+ * No need to synchronize_rcu() here because dsa_ptr in not going away
+ * before it will be zeroed
*/
- wmb();
-
- dev->dsa_ptr = cpu_dp;
dsa_conduit_set_promiscuity(dev, 1);
@@ -418,13 +431,12 @@ void dsa_conduit_teardown(struct net_device *dev)
dsa_conduit_reset_mtu(dev);
dsa_conduit_set_promiscuity(dev, -1);
- dev->dsa_ptr = NULL;
-
/* If we used a tagging format that doesn't have an ethertype
* field, make sure that all packets from this point get sent
* without the tag and go through the regular receive path.
*/
- wmb();
+ rcu_assign_pointer(dev->dsa_ptr, NULL);
+ synchronize_rcu();
}
int dsa_conduit_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp,
@@ -434,7 +446,7 @@ int dsa_conduit_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp,
bool conduit_setup = false;
int err;
- if (!netdev_uses_dsa(lag_dev)) {
+ if (!__netdev_uses_dsa_currently(lag_dev)) {
err = dsa_conduit_setup(lag_dev, cpu_dp);
if (err)
return err;
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 668c729946ea..36b9ebddc8b8 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -976,6 +976,8 @@ static int dsa_tree_bind_tag_proto(struct dsa_switch_tree *dst,
/* Since the dsa/tagging sysfs device attribute is per conduit, the assumption
* is that all DSA switches within a tree share the same tagger, otherwise
* they would have formed disjoint trees (different "dsa,member" values).
+ *
+ * Must be called with RTNL lock held.
*/
int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst,
const struct dsa_device_ops *tag_ops,
@@ -985,8 +987,7 @@ int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst,
struct dsa_port *dp;
int err = -EBUSY;
- if (!rtnl_trylock())
- return restart_syscall();
+ ASSERT_RTNL();
/* At the moment we don't allow changing the tag protocol under
* traffic. The rtnl_mutex also happens to serialize concurrent
@@ -1011,15 +1012,12 @@ int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst,
if (err)
goto out_unwind_tagger;
- rtnl_unlock();
-
return 0;
out_unwind_tagger:
info.tag_ops = old_tag_ops;
dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO, &info);
out_unlock:
- rtnl_unlock();
return err;
}
@@ -1027,7 +1025,7 @@ static void dsa_tree_conduit_state_change(struct dsa_switch_tree *dst,
struct net_device *conduit)
{
struct dsa_notifier_conduit_state_info info;
- struct dsa_port *cpu_dp = conduit->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr);
info.conduit = conduit;
info.operational = dsa_port_conduit_is_operational(cpu_dp);
@@ -1039,7 +1037,7 @@ void dsa_tree_conduit_admin_state_change(struct dsa_switch_tree *dst,
struct net_device *conduit,
bool up)
{
- struct dsa_port *cpu_dp = conduit->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr);
bool notify = false;
/* Don't keep track of admin state on LAG DSA conduits,
@@ -1062,7 +1060,7 @@ void dsa_tree_conduit_oper_state_change(struct dsa_switch_tree *dst,
struct net_device *conduit,
bool up)
{
- struct dsa_port *cpu_dp = conduit->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr);
bool notify = false;
/* Don't keep track of oper state on LAG DSA conduits,
@@ -1594,10 +1592,11 @@ void dsa_switch_shutdown(struct dsa_switch *ds)
}
/* Disconnect from further netdevice notifiers on the conduit,
- * since netdev_uses_dsa() will now return false.
+ * from now on, netdev_uses_dsa_currently() will return false.
*/
dsa_switch_for_each_cpu_port(dp, ds)
- dp->conduit->dsa_ptr = NULL;
+ rcu_assign_pointer(dp->conduit->dsa_ptr, NULL);
+ synchronize_rcu();
rtnl_unlock();
out:
diff --git a/net/dsa/port.c b/net/dsa/port.c
index 25258b33e59e..6220c520d776 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -11,6 +11,7 @@
#include <linux/notifier.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
+#include <linux/rtnetlink.h>
#include "dsa.h"
#include "port.h"
@@ -1414,7 +1415,7 @@ static int dsa_port_assign_conduit(struct dsa_port *dp,
if (err && fail_on_err)
return err;
- dp->cpu_dp = conduit->dsa_ptr;
+ dp->cpu_dp = rtnl_dereference(conduit->dsa_ptr);
dp->cpu_port_in_lag = netif_is_lag_master(conduit);
return 0;
diff --git a/net/dsa/tag.c b/net/dsa/tag.c
index 79ad105902d9..ba662adecc14 100644
--- a/net/dsa/tag.c
+++ b/net/dsa/tag.c
@@ -10,6 +10,7 @@
#include <linux/netdevice.h>
#include <linux/ptp_classify.h>
#include <linux/skbuff.h>
+#include <linux/rcupdate.h>
#include <net/dsa.h>
#include <net/dst_metadata.h>
@@ -55,7 +56,7 @@ static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *unused)
{
struct metadata_dst *md_dst = skb_metadata_dst(skb);
- struct dsa_port *cpu_dp = dev->dsa_ptr;
+ struct dsa_port *cpu_dp = rcu_dereference(dev->dsa_ptr);
struct sk_buff *nskb = NULL;
struct dsa_user_priv *p;
diff --git a/net/dsa/tag.h b/net/dsa/tag.h
index d5707870906b..dbb2217d4344 100644
--- a/net/dsa/tag.h
+++ b/net/dsa/tag.h
@@ -5,6 +5,7 @@
#include <linux/if_vlan.h>
#include <linux/list.h>
+#include <linux/rcupdate.h>
#include <linux/types.h>
#include <net/dsa.h>
@@ -32,11 +33,14 @@ static inline int dsa_tag_protocol_overhead(const struct dsa_device_ops *ops)
static inline struct net_device *dsa_conduit_find_user(struct net_device *dev,
int device, int port)
{
- struct dsa_port *cpu_dp = dev->dsa_ptr;
- struct dsa_switch_tree *dst = cpu_dp->dst;
+ struct dsa_port *cpu_dp;
struct dsa_port *dp;
- list_for_each_entry(dp, &dst->ports, list)
+ cpu_dp = rcu_dereference(dev->dsa_ptr);
+ if (!cpu_dp)
+ return NULL;
+
+ list_for_each_entry(dp, &cpu_dp->dst->ports, list)
if (dp->ds->index == device && dp->index == port &&
dp->type == DSA_PORT_TYPE_USER)
return dp->user;
@@ -184,14 +188,17 @@ static inline struct sk_buff *dsa_software_vlan_untag(struct sk_buff *skb)
static inline struct net_device *
dsa_find_designated_bridge_port_by_vid(struct net_device *conduit, u16 vid)
{
- struct dsa_port *cpu_dp = conduit->dsa_ptr;
- struct dsa_switch_tree *dst = cpu_dp->dst;
+ struct dsa_port *cpu_dp;
struct bridge_vlan_info vinfo;
struct net_device *user;
struct dsa_port *dp;
int err;
- list_for_each_entry(dp, &dst->ports, list) {
+ cpu_dp = rcu_dereference(conduit->dsa_ptr);
+ if (!cpu_dp)
+ return NULL;
+
+ list_for_each_entry(dp, &cpu_dp->dst->ports, list) {
if (dp->type != DSA_PORT_TYPE_USER)
continue;
diff --git a/net/dsa/tag_8021q.c b/net/dsa/tag_8021q.c
index 3ee53e28ec2e..c9fb4fd2a4cf 100644
--- a/net/dsa/tag_8021q.c
+++ b/net/dsa/tag_8021q.c
@@ -5,6 +5,7 @@
* primitives for taggers that rely on 802.1Q VLAN tags to use.
*/
#include <linux/if_vlan.h>
+#include <linux/rcupdate.h>
#include <linux/dsa/8021q.h>
#include "port.h"
@@ -474,14 +475,17 @@ EXPORT_SYMBOL_GPL(dsa_8021q_xmit);
static struct net_device *
dsa_tag_8021q_find_port_by_vbid(struct net_device *conduit, int vbid)
{
- struct dsa_port *cpu_dp = conduit->dsa_ptr;
- struct dsa_switch_tree *dst = cpu_dp->dst;
+ struct dsa_port *cpu_dp;
struct dsa_port *dp;
if (WARN_ON(!vbid))
return NULL;
- dsa_tree_for_each_user_port(dp, dst) {
+ cpu_dp = rcu_dereference(conduit->dsa_ptr);
+ if (!cpu_dp)
+ return NULL;
+
+ dsa_tree_for_each_user_port(dp, cpu_dp->dst) {
if (!dp->bridge)
continue;
diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index 8c3c068728e5..c87f16cd959f 100644
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -269,7 +269,7 @@ static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
return NULL;
/* VLAN tag is added by BCM63xx internal switch */
- if (netdev_uses_dsa(skb->dev))
+ if (__netdev_uses_dsa_currently(skb->dev))
len += VLAN_HLEN;
/* Remove Broadcom tag and update checksum */
diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c
index 2a2c4fb61a65..7f5dc8d384c9 100644
--- a/net/dsa/tag_dsa.c
+++ b/net/dsa/tag_dsa.c
@@ -48,6 +48,7 @@
#include <linux/dsa/mv88e6xxx.h>
#include <linux/etherdevice.h>
#include <linux/list.h>
+#include <linux/rcupdate.h>
#include <linux/slab.h>
#include "tag.h"
@@ -257,14 +258,15 @@ static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
source_port = (dsa_header[1] >> 3) & 0x1f;
if (trunk) {
- struct dsa_port *cpu_dp = dev->dsa_ptr;
- struct dsa_lag *lag;
+ struct dsa_port *cpu_dp = rcu_dereference(dev->dsa_ptr);
+ struct dsa_lag *lag = NULL;
/* The exact source port is not available in the tag,
* so we inject the frame directly on the upper
* team/bond.
*/
- lag = dsa_lag_by_id(cpu_dp->dst, source_port + 1);
+ if (cpu_dp)
+ lag = dsa_lag_by_id(cpu_dp->dst, source_port + 1);
skb->dev = lag ? lag->dev : NULL;
} else {
skb->dev = dsa_conduit_find_user(dev, source_device,
diff --git a/net/dsa/tag_qca.c b/net/dsa/tag_qca.c
index 0cf61286b426..dbc1f659ed07 100644
--- a/net/dsa/tag_qca.c
+++ b/net/dsa/tag_qca.c
@@ -5,6 +5,7 @@
#include <linux/etherdevice.h>
#include <linux/bitfield.h>
+#include <linux/rcupdate.h>
#include <net/dsa.h>
#include <linux/dsa/tag_qca.h>
@@ -36,8 +37,8 @@ static struct sk_buff *qca_tag_xmit(struct sk_buff *skb, struct net_device *dev)
static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev)
{
struct qca_tagger_data *tagger_data;
- struct dsa_port *dp = dev->dsa_ptr;
- struct dsa_switch *ds = dp->ds;
+ struct dsa_port *dp;
+ struct dsa_switch *ds;
u8 ver, pk_type;
__be16 *phdr;
int port;
@@ -45,6 +46,11 @@ static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev)
BUILD_BUG_ON(sizeof(struct qca_mgmt_ethhdr) != QCA_HDR_MGMT_HEADER_LEN + QCA_HDR_LEN);
+ dp = rcu_dereference(dev->dsa_ptr);
+ if (!dp)
+ return NULL;
+ ds = dp->ds;
+
tagger_data = ds->tagger_data;
if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN)))
diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index 3e902af7eea6..0746a7d34178 100644
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c
@@ -5,6 +5,7 @@
#include <linux/dsa/sja1105.h>
#include <linux/dsa/8021q.h>
#include <linux/packing.h>
+#include <linux/rcupdate.h>
#include "tag.h"
#include "tag_8021q.h"
@@ -530,12 +531,13 @@ static struct sk_buff *sja1110_rcv_meta(struct sk_buff *skb, u16 rx_header)
int n_ts = SJA1110_RX_HEADER_N_TS(rx_header);
struct sja1105_tagger_data *tagger_data;
struct net_device *conduit = skb->dev;
+ struct dsa_switch *ds = NULL;
struct dsa_port *cpu_dp;
- struct dsa_switch *ds;
int i;
- cpu_dp = conduit->dsa_ptr;
- ds = dsa_switch_find(cpu_dp->dst->index, switch_id);
+ cpu_dp = rcu_dereference(conduit->dsa_ptr);
+ if (cpu_dp)
+ ds = dsa_switch_find(cpu_dp->dst->index, switch_id);
if (!ds) {
net_err_ratelimited("%s: cannot find switch id %d\n",
conduit->name, switch_id);
@@ -662,24 +664,26 @@ static struct sk_buff *sja1110_rcv(struct sk_buff *skb,
return skb;
}
-static void sja1105_flow_dissect(const struct sk_buff *skb, __be16 *proto,
- int *offset)
+static void sja1105_flow_dissect(const struct sk_buff *skb,
+ const struct dsa_port *dp,
+ __be16 *proto, int *offset)
{
/* No tag added for management frames, all ok */
if (unlikely(sja1105_is_link_local(skb)))
return;
- dsa_tag_generic_flow_dissect(skb, proto, offset);
+ dsa_tag_generic_flow_dissect(skb, dp, proto, offset);
}
-static void sja1110_flow_dissect(const struct sk_buff *skb, __be16 *proto,
- int *offset)
+static void sja1110_flow_dissect(const struct sk_buff *skb,
+ const struct dsa_port *dp,
+ __be16 *proto, int *offset)
{
/* Management frames have 2 DSA tags on RX, so the needed_headroom we
* declared is fine for the generic dissector adjustment procedure.
*/
if (unlikely(sja1105_is_link_local(skb)))
- return dsa_tag_generic_flow_dissect(skb, proto, offset);
+ return dsa_tag_generic_flow_dissect(skb, dp, proto, offset);
/* For the rest, there is a single DSA tag, the tag_8021q one */
*offset = VLAN_HLEN;
diff --git a/net/dsa/user.c b/net/dsa/user.c
index f5adfa1d978a..2afd21e34772 100644
--- a/net/dsa/user.c
+++ b/net/dsa/user.c
@@ -21,6 +21,7 @@
#include <linux/if_hsr.h>
#include <net/dcbnl.h>
#include <linux/netpoll.h>
+#include <linux/rcupdate.h>
#include <linux/string.h>
#include "conduit.h"
@@ -2839,7 +2840,7 @@ int dsa_user_change_conduit(struct net_device *dev, struct net_device *conduit,
return -EOPNOTSUPP;
}
- if (!netdev_uses_dsa(conduit)) {
+ if (!__netdev_uses_dsa_currently(conduit)) {
NL_SET_ERR_MSG_MOD(extack,
"Interface not eligible as DSA conduit");
return -EOPNOTSUPP;
@@ -3141,8 +3142,8 @@ static int dsa_lag_conduit_validate(struct net_device *lag_dev,
netdev_for_each_lower_dev(lag_dev, lower1, iter1) {
netdev_for_each_lower_dev(lag_dev, lower2, iter2) {
- if (!netdev_uses_dsa(lower1) ||
- !netdev_uses_dsa(lower2)) {
+ if (!__netdev_uses_dsa_currently(lower1) ||
+ !__netdev_uses_dsa_currently(lower2)) {
NL_SET_ERR_MSG_MOD(extack,
"All LAG ports must be eligible as DSA conduits");
return notifier_from_errno(-EINVAL);
@@ -3151,8 +3152,8 @@ static int dsa_lag_conduit_validate(struct net_device *lag_dev,
if (lower1 == lower2)
continue;
- if (!dsa_port_tree_same(lower1->dsa_ptr,
- lower2->dsa_ptr)) {
+ if (!dsa_port_tree_same(rtnl_dereference(lower1->dsa_ptr),
+ rtnl_dereference(lower2->dsa_ptr))) {
NL_SET_ERR_MSG_MOD(extack,
"LAG contains DSA conduits of disjoint switch trees");
return notifier_from_errno(-EINVAL);
@@ -3169,7 +3170,7 @@ dsa_conduit_prechangeupper_sanity_check(struct net_device *conduit,
{
struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(&info->info);
- if (!netdev_uses_dsa(conduit))
+ if (!__netdev_uses_dsa_currently(conduit))
return NOTIFY_DONE;
if (!info->linking)
@@ -3205,20 +3206,22 @@ dsa_lag_conduit_prechangelower_sanity_check(struct net_device *dev,
struct net_device *lower;
struct list_head *iter;
- if (!netdev_uses_dsa(lag_dev) || !netif_is_lag_master(lag_dev))
+ if (!__netdev_uses_dsa_currently(lag_dev) ||
+ !netif_is_lag_master(lag_dev))
return NOTIFY_DONE;
if (!info->linking)
return NOTIFY_DONE;
- if (!netdev_uses_dsa(dev)) {
+ if (!__netdev_uses_dsa_currently(dev)) {
NL_SET_ERR_MSG(extack,
"Only DSA conduits can join a LAG DSA conduit");
return notifier_from_errno(-EINVAL);
}
netdev_for_each_lower_dev(lag_dev, lower, iter) {
- if (!dsa_port_tree_same(dev->dsa_ptr, lower->dsa_ptr)) {
+ if (!dsa_port_tree_same(rtnl_dereference(dev->dsa_ptr),
+ rtnl_dereference(lower->dsa_ptr))) {
NL_SET_ERR_MSG(extack,
"Interface is DSA conduit for a different switch tree than this LAG");
return notifier_from_errno(-EINVAL);
@@ -3257,7 +3260,8 @@ dsa_bridge_prechangelower_sanity_check(struct net_device *new_lower,
extack = netdev_notifier_info_to_extack(&info->info);
netdev_for_each_lower_dev(br, lower, iter) {
- if (!netdev_uses_dsa(new_lower) && !netdev_uses_dsa(lower))
+ if (!__netdev_uses_dsa_currently(new_lower) &&
+ !__netdev_uses_dsa_currently(lower))
continue;
if (!netdev_port_same_parent_id(lower, new_lower)) {
@@ -3295,7 +3299,7 @@ static int dsa_conduit_lag_join(struct net_device *conduit,
struct netdev_lag_upper_info *uinfo,
struct netlink_ext_ack *extack)
{
- struct dsa_port *cpu_dp = conduit->dsa_ptr;
+ struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr);
struct dsa_switch_tree *dst = cpu_dp->dst;
struct dsa_port *dp;
int err;
@@ -3328,7 +3332,7 @@ static int dsa_conduit_lag_join(struct net_device *conduit,
}
}
- dsa_conduit_lag_teardown(lag_dev, conduit->dsa_ptr);
+ dsa_conduit_lag_teardown(lag_dev, rtnl_dereference(conduit->dsa_ptr));
return err;
}
@@ -3336,17 +3340,16 @@ static int dsa_conduit_lag_join(struct net_device *conduit,
static void dsa_conduit_lag_leave(struct net_device *conduit,
struct net_device *lag_dev)
{
- struct dsa_port *dp, *cpu_dp = lag_dev->dsa_ptr;
+ struct dsa_port *dp, *cpu_dp = rtnl_dereference(lag_dev->dsa_ptr);
struct dsa_switch_tree *dst = cpu_dp->dst;
struct dsa_port *new_cpu_dp = NULL;
struct net_device *lower;
struct list_head *iter;
netdev_for_each_lower_dev(lag_dev, lower, iter) {
- if (netdev_uses_dsa(lower)) {
- new_cpu_dp = lower->dsa_ptr;
+ new_cpu_dp = rtnl_dereference(lower->dsa_ptr);
+ if (new_cpu_dp)
break;
- }
}
if (new_cpu_dp) {
@@ -3360,8 +3363,11 @@ static void dsa_conduit_lag_leave(struct net_device *conduit,
/* Update the index of the virtual CPU port to match the lowest
* physical CPU port
*/
- lag_dev->dsa_ptr = new_cpu_dp;
- wmb();
+ rcu_assign_pointer(lag_dev->dsa_ptr, new_cpu_dp);
+ /*
+ * No need to synchronize_rcu() here because dsa_ptr in not
+ * going away before it will be zeroed
+ */
} else {
/* If the LAG DSA conduit has no ports left, migrate back all
* user ports to the first physical CPU port
@@ -3372,7 +3378,7 @@ static void dsa_conduit_lag_leave(struct net_device *conduit,
/* This DSA conduit has left its LAG in any case, so let
* the CPU port leave the hardware LAG as well
*/
- dsa_conduit_lag_teardown(lag_dev, conduit->dsa_ptr);
+ dsa_conduit_lag_teardown(lag_dev, rtnl_dereference(conduit->dsa_ptr));
}
static int dsa_conduit_changeupper(struct net_device *dev,
@@ -3381,7 +3387,7 @@ static int dsa_conduit_changeupper(struct net_device *dev,
struct netlink_ext_ack *extack;
int err = NOTIFY_DONE;
- if (!netdev_uses_dsa(dev))
+ if (!__netdev_uses_dsa_currently(dev))
return err;
extack = netdev_notifier_info_to_extack(&info->info);
@@ -3464,14 +3470,14 @@ static int dsa_user_netdevice_event(struct notifier_block *nb,
err = dsa_port_lag_change(dp, info->lower_state_info);
}
+ dp = rtnl_dereference(dev->dsa_ptr);
+ if (!dp)
+ return NOTIFY_OK;
+
/* Mirror LAG port events on DSA conduits that are in
* a LAG towards their respective switch CPU ports
*/
- if (netdev_uses_dsa(dev)) {
- dp = dev->dsa_ptr;
-
- err = dsa_port_lag_change(dp, info->lower_state_info);
- }
+ err = dsa_port_lag_change(dp, info->lower_state_info);
return notifier_from_errno(err);
}
@@ -3481,39 +3487,41 @@ static int dsa_user_netdevice_event(struct notifier_block *nb,
* DSA driver may require the conduit port (and indirectly
* the tagger) to be available for some special operation.
*/
- if (netdev_uses_dsa(dev)) {
- struct dsa_port *cpu_dp = dev->dsa_ptr;
- struct dsa_switch_tree *dst = cpu_dp->ds->dst;
-
- /* Track when the conduit port is UP */
- dsa_tree_conduit_oper_state_change(dst, dev,
- netif_oper_up(dev));
-
- /* Track when the conduit port is ready and can accept
- * packet.
- * NETDEV_UP event is not enough to flag a port as ready.
- * We also have to wait for linkwatch_do_dev to dev_activate
- * and emit a NETDEV_CHANGE event.
- * We check if a conduit port is ready by checking if the dev
- * have a qdisc assigned and is not noop.
- */
- dsa_tree_conduit_admin_state_change(dst, dev,
- !qdisc_tx_is_noop(dev));
+ struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);
+ struct dsa_switch_tree *dst;
- return NOTIFY_OK;
- }
+ if (!cpu_dp)
+ return NOTIFY_DONE;
+
+ dst = cpu_dp->ds->dst;
+
+ /* Track when the conduit port is UP */
+ dsa_tree_conduit_oper_state_change(dst, dev,
+ netif_oper_up(dev));
+
+ /* Track when the conduit port is ready and can accept
+ * packet.
+ * NETDEV_UP event is not enough to flag a port as ready.
+ * We also have to wait for linkwatch_do_dev to dev_activate
+ * and emit a NETDEV_CHANGE event.
+ * We check if a conduit port is ready by checking if the dev
+ * have a qdisc assigned and is not noop.
+ */
+ dsa_tree_conduit_admin_state_change(dst, dev,
+ !qdisc_tx_is_noop(dev));
+
+ return NOTIFY_OK;
- return NOTIFY_DONE;
}
case NETDEV_GOING_DOWN: {
struct dsa_port *dp, *cpu_dp;
struct dsa_switch_tree *dst;
LIST_HEAD(close_list);
- if (!netdev_uses_dsa(dev))
+ cpu_dp = rtnl_dereference(dev->dsa_ptr);
+ if (!cpu_dp)
return NOTIFY_DONE;
- cpu_dp = dev->dsa_ptr;
dst = cpu_dp->ds->dst;
dsa_tree_conduit_admin_state_change(dst, dev, false);
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index 4e3651101b86..a05ff82551c3 100644
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c
@@ -170,7 +170,7 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
* variants has been configured on the receiving interface,
* and if so, set skb->protocol without looking at the packet.
*/
- if (unlikely(netdev_uses_dsa(dev)))
+ if (unlikely(netdev_uses_dsa_currently(dev)))
return htons(ETH_P_XDSA);
if (likely(eth_proto_is_802_3(eth->h_proto)))
--
2.46.0
^ permalink raw reply related [flat|nested] 12+ messages in thread