FAILED: patch "[PATCH] net: macb: initialize PTP state before registering clock" failed to apply to 5.10-stable tree

FAILED: patch "[PATCH] net: macb: initialize PTP state before registering clock" failed to apply to 5.10-stable tree

[gregkh]

The patch below does not apply to the 5.10-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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x e1406330d70e56dd44fa6fbafc86e77e5c80c122
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026091649-armoire-absurd-8a42@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

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

From e1406330d70e56dd44fa6fbafc86e77e5c80c122 Mon Sep 17 00:00:00 2001
From: Runyu Xiao <runyu.xiao@seu.edu.cn>
Date: Tue, 8 Sep 2026 18:39:24 +0800
Subject: [PATCH] net: macb: initialize PTP state before registering clock
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

gem_ptp_init() registers the PTP clock before initializing
bp->tsu_clk_lock and the TSU hardware. Since ptp_clock_register()
publishes the PTP character device, userspace may invoke PTP callbacks
before the lock and hardware are ready.

In addition, gem_ptp_init() is called from both the interface open and
resume paths. Reinitializing tsu_clk_lock there can reset the lock while
timestamp processing is using it.

This race is theoretical and has not been observed in practice.

Initialize tsu_clk_lock once during probe and initialize the TSU before
registering the PTP clock.

Fixes: ab91f0a9b5f4 ("net: macb: Add hardware PTP support")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/netdev/20260904030439.3994047-1-runyu.xiao@seu.edu.cn/
Reviewed-by: Théo Lebrun <theo.lebrun@bootlin.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Link: https://patch.msgid.link/20260908103924.607033-1-runyu.xiao@seu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 77dec2d6e3fb..4cb5d7088d43 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -5883,6 +5883,7 @@ static int macb_probe(struct platform_device *pdev)
 	}
 	spin_lock_init(&bp->lock);
 	spin_lock_init(&bp->stats_lock);
+	spin_lock_init(&bp->tsu_clk_lock);
 
 	/* setup capabilities */
 	macb_configure_caps(bp, macb_config);
diff --git a/drivers/net/ethernet/cadence/macb_ptp.c b/drivers/net/ethernet/cadence/macb_ptp.c
index e5195d7dac1d..6d9166389988 100644
--- a/drivers/net/ethernet/cadence/macb_ptp.c
+++ b/drivers/net/ethernet/cadence/macb_ptp.c
@@ -334,6 +334,7 @@ void gem_ptp_init(struct net_device *netdev)
 	bp->tsu_rate = bp->ptp_info->get_tsu_rate(bp);
 	bp->ptp_clock_info.max_adj = bp->ptp_info->get_ptp_max_adj();
 	gem_ptp_init_timer(bp);
+	gem_ptp_init_tsu(bp);
 	bp->ptp_clock = ptp_clock_register(&bp->ptp_clock_info, &netdev->dev);
 	if (IS_ERR(bp->ptp_clock)) {
 		pr_err("ptp clock register failed: %ld\n",
@@ -345,10 +346,6 @@ void gem_ptp_init(struct net_device *netdev)
 		return;
 	}
 
-	spin_lock_init(&bp->tsu_clk_lock);
-
-	gem_ptp_init_tsu(bp);
-
 	dev_info(&bp->pdev->dev, "%s ptp clock registered.\n",
 		 GEM_PTP_TIMER_NAME);
 }

[PATCH 5.10.y 1/2] net: macb: unify device pointer naming convention

[Sasha Levin]

From: Théo Lebrun <theo.lebrun@bootlin.com>

[ Upstream commit 07362f68e61d82ee53da0e9ae2c7f981c3538861 ]

Here are all device pointer variable permutations inside MACB:

   struct device *dev;
   struct net_device *dev;
   struct net_device *ndev;
   struct net_device *netdev;
   struct pci_dev *pdev;              // inside macb_pci.c
   struct phy_device *phy;
   struct phy_device *phydev;
   struct platform_device *pdev;
   struct platform_device *plat_dev;  // inside macb_pci.c

Unify to this convention:

   struct device *dev;
   struct net_device *netdev;
   struct pci_dev *pci;
   struct phy_device *phydev;
   struct platform_device *pdev;

Ensure nothing slipped through using ctags tooling:

⟩ ctags -o - --kinds-c='{local}{member}{parameter}' \
    --fields='{typeref}' drivers/net/ethernet/cadence/* | \
  awk -F"\t" '
    $NF~/struct:.*(device|dev) / {print $NF, $1}' | \
  sort -u
typeref:struct:device * dev
typeref:struct:in_device * idev        // ignored
typeref:struct:net_device * netdev
typeref:struct:pci_dev * pci
typeref:struct:phy_device * phydev
typeref:struct:platform_device * pdev

Also fix some printk() calls to use __func__ instead of hardcoding.
This silences some checkpatch.pl warnings and doesn't deserve a
separate commit.

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Nicolai Buchwitz <nb@tipi-net.de>
Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Link: https://patch.msgid.link/20260812-macb-context-v9-2-7ddbf5f715e0@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Keep only the net_device argument rename for gem_ptp_init(), together
with its callback, declaration and disabled-PTP stub. The other naming
changes are unrelated to the PTP initialization fix and conflict with
driver APIs and code paths that differ substantially in Linux 5.10.

Linux 5.10 still initializes per-queue deferred TX timestamp state in
gem_ptp_init(). Move that existing loop to the start of the function,
preserving its counters and work initialization. This keeps the lock and
TSU initialization block contiguous so that target commit
e1406330d70e56dd44fa6fbafc86e77e5c80c122 applies without conflicts.

The target remains responsible for initializing tsu_clk_lock once at probe
and initializing the TSU before publishing the PTP clock. No functions or
newer driver APIs are introduced by this dependency backport.

[ sashal: Reduced backport -- upstream 07362f68e61d8 touches 4 file(s), this
  backport carries 2. Not backported here:
  drivers/net/ethernet/cadence/macb_main.c
  drivers/net/ethernet/cadence/macb_pci.c
  This note is generated from the file lists only; see the resolution record
  for the reasoning. ]

Stable-dep-of: e1406330d70e ("net: macb: initialize PTP state before registering clock")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/cadence/macb.h     |  6 +++---
 drivers/net/ethernet/cadence/macb_ptp.c | 17 +++++++++--------
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index 7ce391209cdd1..0b507def88616 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -1087,7 +1087,7 @@ struct macb_or_gem_ops {
 
 /* MACB-PTP interface: adapt to platform needs. */
 struct macb_ptp_info {
-	void (*ptp_init)(struct net_device *ndev);
+	void (*ptp_init)(struct net_device *netdev);
 	void (*ptp_remove)(struct net_device *ndev);
 	s32 (*get_ptp_max_adj)(void);
 	unsigned int (*get_tsu_rate)(struct macb *bp);
@@ -1260,7 +1260,7 @@ enum macb_bd_control {
 	TSTAMP_ALL_FRAMES,
 };
 
-void gem_ptp_init(struct net_device *ndev);
+void gem_ptp_init(struct net_device *netdev);
 void gem_ptp_remove(struct net_device *ndev);
 int gem_ptp_txstamp(struct macb_queue *queue, struct sk_buff *skb, struct macb_dma_desc *des);
 void gem_ptp_rxstamp(struct macb *bp, struct sk_buff *skb, struct macb_dma_desc *desc);
@@ -1282,7 +1282,7 @@ static inline void gem_ptp_do_rxstamp(struct macb *bp, struct sk_buff *skb, stru
 int gem_get_hwtst(struct net_device *dev, struct ifreq *rq);
 int gem_set_hwtst(struct net_device *dev, struct ifreq *ifr, int cmd);
 #else
-static inline void gem_ptp_init(struct net_device *ndev) { }
+static inline void gem_ptp_init(struct net_device *netdev) { }
 static inline void gem_ptp_remove(struct net_device *ndev) { }
 
 static inline int gem_ptp_do_txstamp(struct macb_queue *queue, struct sk_buff *skb, struct macb_dma_desc *desc)
diff --git a/drivers/net/ethernet/cadence/macb_ptp.c b/drivers/net/ethernet/cadence/macb_ptp.c
index d0063495a4a71..1faca23dc3ccc 100644
--- a/drivers/net/ethernet/cadence/macb_ptp.c
+++ b/drivers/net/ethernet/cadence/macb_ptp.c
@@ -355,19 +355,25 @@ static void gem_tx_timestamp_flush(struct work_struct *work)
 	}
 }
 
-void gem_ptp_init(struct net_device *dev)
+void gem_ptp_init(struct net_device *netdev)
 {
-	struct macb *bp = netdev_priv(dev);
+	struct macb *bp = netdev_priv(netdev);
 	struct macb_queue *queue;
 	unsigned int q;
 
+	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) {
+		queue->tx_ts_head = 0;
+		queue->tx_ts_tail = 0;
+		INIT_WORK(&queue->tx_ts_task, gem_tx_timestamp_flush);
+	}
+
 	bp->ptp_clock_info = gem_ptp_caps_template;
 
 	/* nominal frequency and maximum adjustment in ppb */
 	bp->tsu_rate = bp->ptp_info->get_tsu_rate(bp);
 	bp->ptp_clock_info.max_adj = bp->ptp_info->get_ptp_max_adj();
 	gem_ptp_init_timer(bp);
-	bp->ptp_clock = ptp_clock_register(&bp->ptp_clock_info, &dev->dev);
+	bp->ptp_clock = ptp_clock_register(&bp->ptp_clock_info, &netdev->dev);
 	if (IS_ERR(bp->ptp_clock)) {
 		pr_err("ptp clock register failed: %ld\n",
 			PTR_ERR(bp->ptp_clock));
@@ -379,11 +385,6 @@ void gem_ptp_init(struct net_device *dev)
 	}
 
 	spin_lock_init(&bp->tsu_clk_lock);
-	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) {
-		queue->tx_ts_head = 0;
-		queue->tx_ts_tail = 0;
-		INIT_WORK(&queue->tx_ts_task, gem_tx_timestamp_flush);
-	}
 
 	gem_ptp_init_tsu(bp);
 
-- 
2.53.0

[PATCH 5.10.y 2/2] net: macb: initialize PTP state before registering clock

[Sasha Levin]

From: Runyu Xiao <runyu.xiao@seu.edu.cn>

[ Upstream commit e1406330d70e56dd44fa6fbafc86e77e5c80c122 ]

gem_ptp_init() registers the PTP clock before initializing
bp->tsu_clk_lock and the TSU hardware. Since ptp_clock_register()
publishes the PTP character device, userspace may invoke PTP callbacks
before the lock and hardware are ready.

In addition, gem_ptp_init() is called from both the interface open and
resume paths. Reinitializing tsu_clk_lock there can reset the lock while
timestamp processing is using it.

This race is theoretical and has not been observed in practice.

Initialize tsu_clk_lock once during probe and initialize the TSU before
registering the PTP clock.

Fixes: ab91f0a9b5f4 ("net: macb: Add hardware PTP support")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/netdev/20260904030439.3994047-1-runyu.xiao@seu.edu.cn/
Reviewed-by: Théo Lebrun <theo.lebrun@bootlin.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Link: https://patch.msgid.link/20260908103924.607033-1-runyu.xiao@seu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/cadence/macb_main.c | 1 +
 drivers/net/ethernet/cadence/macb_ptp.c  | 5 +----
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 8751d6ea9a5e8..1e7402823eb36 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -4568,6 +4568,7 @@ static int macb_probe(struct platform_device *pdev)
 
 	spin_lock_init(&bp->lock);
 	spin_lock_init(&bp->stats_lock);
+	spin_lock_init(&bp->tsu_clk_lock);
 
 	/* setup capabilities */
 	macb_configure_caps(bp, macb_config);
diff --git a/drivers/net/ethernet/cadence/macb_ptp.c b/drivers/net/ethernet/cadence/macb_ptp.c
index 1faca23dc3ccc..ebb3b5dc8ebdc 100644
--- a/drivers/net/ethernet/cadence/macb_ptp.c
+++ b/drivers/net/ethernet/cadence/macb_ptp.c
@@ -373,6 +373,7 @@ void gem_ptp_init(struct net_device *netdev)
 	bp->tsu_rate = bp->ptp_info->get_tsu_rate(bp);
 	bp->ptp_clock_info.max_adj = bp->ptp_info->get_ptp_max_adj();
 	gem_ptp_init_timer(bp);
+	gem_ptp_init_tsu(bp);
 	bp->ptp_clock = ptp_clock_register(&bp->ptp_clock_info, &netdev->dev);
 	if (IS_ERR(bp->ptp_clock)) {
 		pr_err("ptp clock register failed: %ld\n",
@@ -384,10 +385,6 @@ void gem_ptp_init(struct net_device *netdev)
 		return;
 	}
 
-	spin_lock_init(&bp->tsu_clk_lock);
-
-	gem_ptp_init_tsu(bp);
-
 	dev_info(&bp->pdev->dev, "%s ptp clock registered.\n",
 		 GEM_PTP_TIMER_NAME);
 }
-- 
2.53.0