Mailing List Archive

[PATCH 3/3] net: bcmgenet: synchronize UMAC_CMD access
The UMAC_CMD register is written from different execution
contexts and has insufficient synchronization protections to
prevent possible corruption. Of particular concern are the
acceses from the phy_device delayed work context used by the
adjust_link call and the BH context that may be used by the
ndo_set_rx_mode call.

A spinlock is added to the driver to protect contended register
accesses (i.e. reg_lock) and it is used to synchronize accesses
to UMAC_CMD.

Fixes: 1c1008c793fa ("net: bcmgenet: add main driver file")
Cc: stable@vger.kernel.org
Signed-off-by: Doug Berger <opendmb@gmail.com>
---
drivers/net/ethernet/broadcom/genet/bcmgenet.c | 12 +++++++++++-
drivers/net/ethernet/broadcom/genet/bcmgenet.h | 4 +++-
drivers/net/ethernet/broadcom/genet/bcmgenet_wol.c | 8 +++++++-
drivers/net/ethernet/broadcom/genet/bcmmii.c | 2 ++
4 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index 5452b7dc6e6a..c7e7dac057a3 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -2467,14 +2467,18 @@ static void umac_enable_set(struct bcmgenet_priv *priv, u32 mask, bool enable)
{
u32 reg;

+ spin_lock_bh(&priv->reg_lock);
reg = bcmgenet_umac_readl(priv, UMAC_CMD);
- if (reg & CMD_SW_RESET)
+ if (reg & CMD_SW_RESET) {
+ spin_unlock_bh(&priv->reg_lock);
return;
+ }
if (enable)
reg |= mask;
else
reg &= ~mask;
bcmgenet_umac_writel(priv, reg, UMAC_CMD);
+ spin_unlock_bh(&priv->reg_lock);

/* UniMAC stops on a packet boundary, wait for a full-size packet
* to be processed
@@ -2490,8 +2494,10 @@ static void reset_umac(struct bcmgenet_priv *priv)
udelay(10);

/* issue soft reset and disable MAC while updating its registers */
+ spin_lock_bh(&priv->reg_lock);
bcmgenet_umac_writel(priv, CMD_SW_RESET, UMAC_CMD);
udelay(2);
+ spin_unlock_bh(&priv->reg_lock);
}

static void bcmgenet_intr_disable(struct bcmgenet_priv *priv)
@@ -3597,16 +3603,19 @@ static void bcmgenet_set_rx_mode(struct net_device *dev)
* 3. The number of filters needed exceeds the number filters
* supported by the hardware.
*/
+ spin_lock(&priv->reg_lock);
reg = bcmgenet_umac_readl(priv, UMAC_CMD);
if ((dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) ||
(nfilter > MAX_MDF_FILTER)) {
reg |= CMD_PROMISC;
bcmgenet_umac_writel(priv, reg, UMAC_CMD);
+ spin_unlock(&priv->reg_lock);
bcmgenet_umac_writel(priv, 0, UMAC_MDF_CTRL);
return;
} else {
reg &= ~CMD_PROMISC;
bcmgenet_umac_writel(priv, reg, UMAC_CMD);
+ spin_unlock(&priv->reg_lock);
}

/* update MDF filter */
@@ -4005,6 +4014,7 @@ static int bcmgenet_probe(struct platform_device *pdev)
goto err;
}

+ spin_lock_init(&priv->reg_lock);
spin_lock_init(&priv->lock);

/* Set default pause parameters */
diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.h b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
index 7523b60b3c1c..43b923c48b14 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.h
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0-only */
/*
- * Copyright (c) 2014-2020 Broadcom
+ * Copyright (c) 2014-2024 Broadcom
*/

#ifndef __BCMGENET_H__
@@ -573,6 +573,8 @@ struct bcmgenet_rxnfc_rule {
/* device context */
struct bcmgenet_priv {
void __iomem *base;
+ /* reg_lock: lock to serialize access to shared registers */
+ spinlock_t reg_lock;
enum bcmgenet_version version;
struct net_device *dev;

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet_wol.c b/drivers/net/ethernet/broadcom/genet/bcmgenet_wol.c
index 7a41cad5788f..1248792d7fd4 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet_wol.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet_wol.c
@@ -2,7 +2,7 @@
/*
* Broadcom GENET (Gigabit Ethernet) Wake-on-LAN support
*
- * Copyright (c) 2014-2020 Broadcom
+ * Copyright (c) 2014-2024 Broadcom
*/

#define pr_fmt(fmt) "bcmgenet_wol: " fmt
@@ -151,6 +151,7 @@ int bcmgenet_wol_power_down_cfg(struct bcmgenet_priv *priv,
}

/* Can't suspend with WoL if MAC is still in reset */
+ spin_lock_bh(&priv->reg_lock);
reg = bcmgenet_umac_readl(priv, UMAC_CMD);
if (reg & CMD_SW_RESET)
reg &= ~CMD_SW_RESET;
@@ -158,6 +159,7 @@ int bcmgenet_wol_power_down_cfg(struct bcmgenet_priv *priv,
/* disable RX */
reg &= ~CMD_RX_EN;
bcmgenet_umac_writel(priv, reg, UMAC_CMD);
+ spin_unlock_bh(&priv->reg_lock);
mdelay(10);

if (priv->wolopts & (WAKE_MAGIC | WAKE_MAGICSECURE)) {
@@ -203,6 +205,7 @@ int bcmgenet_wol_power_down_cfg(struct bcmgenet_priv *priv,
}

/* Enable CRC forward */
+ spin_lock_bh(&priv->reg_lock);
reg = bcmgenet_umac_readl(priv, UMAC_CMD);
priv->crc_fwd_en = 1;
reg |= CMD_CRC_FWD;
@@ -210,6 +213,7 @@ int bcmgenet_wol_power_down_cfg(struct bcmgenet_priv *priv,
/* Receiver must be enabled for WOL MP detection */
reg |= CMD_RX_EN;
bcmgenet_umac_writel(priv, reg, UMAC_CMD);
+ spin_unlock_bh(&priv->reg_lock);

reg = UMAC_IRQ_MPD_R;
if (hfb_enable)
@@ -256,7 +260,9 @@ void bcmgenet_wol_power_up_cfg(struct bcmgenet_priv *priv,
}

/* Disable CRC Forward */
+ spin_lock_bh(&priv->reg_lock);
reg = bcmgenet_umac_readl(priv, UMAC_CMD);
reg &= ~CMD_CRC_FWD;
bcmgenet_umac_writel(priv, reg, UMAC_CMD);
+ spin_unlock_bh(&priv->reg_lock);
}
diff --git a/drivers/net/ethernet/broadcom/genet/bcmmii.c b/drivers/net/ethernet/broadcom/genet/bcmmii.c
index 86a4aa72b3d4..c4a3698cef66 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmmii.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmmii.c
@@ -76,6 +76,7 @@ static void bcmgenet_mac_config(struct net_device *dev)
reg |= RGMII_LINK;
bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);

+ spin_lock_bh(&priv->reg_lock);
reg = bcmgenet_umac_readl(priv, UMAC_CMD);
reg &= ~((CMD_SPEED_MASK << CMD_SPEED_SHIFT) |
CMD_HD_EN |
@@ -88,6 +89,7 @@ static void bcmgenet_mac_config(struct net_device *dev)
reg |= CMD_TX_EN | CMD_RX_EN;
}
bcmgenet_umac_writel(priv, reg, UMAC_CMD);
+ spin_unlock_bh(&priv->reg_lock);

active = phy_init_eee(phydev, 0) >= 0;
bcmgenet_eee_enable_set(dev,
--
2.34.1