FAILED: patch "[PATCH] net: bcmgenet: synchronize EXT_RGMII_OOB_CTRL access" failed to apply to 5.15-stable tree

FAILED: patch "[PATCH] net: bcmgenet: synchronize EXT_RGMII_OOB_CTRL access" failed to apply to 5.15-stable tree

[gregkh]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x d85cf67a339685beae1d0aee27b7f61da95455be
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024051343-casket-astride-c192@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

d85cf67a3396 ("net: bcmgenet: synchronize EXT_RGMII_OOB_CTRL access")
696450c05181 ("net: bcmgenet: Clear RGMII_LINK upon link down")
fc13d8c03773 ("net: bcmgenet: pull mac_config from adjust_link")
fcb5dfe7dc40 ("net: bcmgenet: remove old link state values")
50e356686fa9 ("net: bcmgenet: remove netif_carrier_off from adjust_link")
b972b54a68b2 ("net: bcmgenet: Patch PHY interface for dedicated PHY driver")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From d85cf67a339685beae1d0aee27b7f61da95455be Mon Sep 17 00:00:00 2001
From: Doug Berger <opendmb@gmail.com>
Date: Thu, 25 Apr 2024 15:27:19 -0700
Subject: [PATCH] net: bcmgenet: synchronize EXT_RGMII_OOB_CTRL access

The EXT_RGMII_OOB_CTRL register can be written from different
contexts. It is predominantly written from the adjust_link
handler which is synchronized by the phydev->lock, but can
also be written from a different context when configuring the
mii in bcmgenet_mii_config().

The chances of contention are quite low, but it is conceivable
that adjust_link could occur during resume when WoL is enabled
so use the phydev->lock synchronizer in bcmgenet_mii_config()
to be sure.

Fixes: afe3f907d20f ("net: bcmgenet: power on MII block for all MII modes")
Cc: stable@vger.kernel.org
Signed-off-by: Doug Berger <opendmb@gmail.com>
Acked-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/genet/bcmmii.c b/drivers/net/ethernet/broadcom/genet/bcmmii.c
index 9ada89355747..86a4aa72b3d4 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmmii.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmmii.c
@@ -2,7 +2,7 @@
 /*
  * Broadcom GENET MDIO routines
  *
- * Copyright (c) 2014-2017 Broadcom
+ * Copyright (c) 2014-2024 Broadcom
  */
 
 #include <linux/acpi.h>
@@ -275,6 +275,7 @@ int bcmgenet_mii_config(struct net_device *dev, bool init)
 	 * block for the interface to work, unconditionally clear the
 	 * Out-of-band disable since we do not need it.
 	 */
+	mutex_lock(&phydev->lock);
 	reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
 	reg &= ~OOB_DISABLE;
 	if (priv->ext_phy) {
@@ -286,6 +287,7 @@ int bcmgenet_mii_config(struct net_device *dev, bool init)
 			reg |= RGMII_MODE_EN;
 	}
 	bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
+	mutex_unlock(&phydev->lock);
 
 	if (init)
 		dev_info(kdev, "configuring instance for %s\n", phy_name);

[PATCH 5.15.y] net: bcmgenet: synchronize EXT_RGMII_OOB_CTRL access

[Doug Berger]

The EXT_RGMII_OOB_CTRL register can be written from different
contexts. It is predominantly written from the adjust_link
handler which is synchronized by the phydev->lock, but can
also be written from a different context when configuring the
mii in bcmgenet_mii_config().

The chances of contention are quite low, but it is conceivable
that adjust_link could occur during resume when WoL is enabled
so use the phydev->lock synchronizer in bcmgenet_mii_config()
to be sure.

Fixes: afe3f907d20f ("net: bcmgenet: power on MII block for all MII modes")
Cc: stable@vger.kernel.org
Signed-off-by: Doug Berger <opendmb@gmail.com>
Acked-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit d85cf67a339685beae1d0aee27b7f61da95455be)
Signed-off-by: Doug Berger <opendmb@gmail.com>
---
 drivers/net/ethernet/broadcom/genet/bcmmii.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/genet/bcmmii.c b/drivers/net/ethernet/broadcom/genet/bcmmii.c
index 51f6c94e919e..6d823c107476 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmmii.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmmii.c
@@ -264,6 +264,7 @@ int bcmgenet_mii_config(struct net_device *dev, bool init)
 	 * block for the interface to work
 	 */
 	if (priv->ext_phy) {
+		mutex_lock(&phydev->lock);
 		reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
 		reg &= ~ID_MODE_DIS;
 		reg |= id_mode_dis;
@@ -272,6 +273,7 @@ int bcmgenet_mii_config(struct net_device *dev, bool init)
 		else
 			reg |= RGMII_MODE_EN;
 		bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
+		mutex_unlock(&phydev->lock);
 	}
 
 	if (init)
-- 
2.34.1