[PATCH 0/4] staging: octeon: Improve initialization error handling

[PATCH 0/4] staging: octeon: Improve initialization error handling

[Prashant Rahul]

Hi all,

The TX and RX initialization paths currently call panic() on some
initialization failures. Instead, these failures should be reported back
to the probe function so that it can unwind any resources acquired during
initialization and fail gracefully.

This series replaces those panic() calls with proper error logging, propagates
the errors to the probe function, and adds the necessary cleanup to avoid
leaving the driver in a partially initialized state.

This is my first time working with drivers, so please let me know if I
have made any mistakes.

Thank you! :3

Signed-off-by: Prashant Rahul <prashantrahul23@gmail.com>
---
Prashant Rahul (4):
      staging: octeon: factor out device removal into a helper
      staging: octeon: Propagate rx initialization failures
      staging: octeon: Propagate tx initialization failures
      staging: octeon: handle rx/tx initialization failures in probe

 drivers/staging/octeon/ethernet-rx.c | 18 ++++++----
 drivers/staging/octeon/ethernet-rx.h |  2 +-
 drivers/staging/octeon/ethernet-tx.c | 17 +++++-----
 drivers/staging/octeon/ethernet-tx.h |  2 +-
 drivers/staging/octeon/ethernet.c    | 65 ++++++++++++++++++++++++++++--------
 5 files changed, 75 insertions(+), 29 deletions(-)
---
base-commit: 4e5dfb7c84012007c3c7061126491bbc92d71bf1
change-id: 20260625-staging-driver-octeon-panic-2602ed8d5d67

Best regards,
-- 
Prashant Rahul <prashantrahul23@gmail.com>

[PATCH 1/4] staging: octeon: factor out device removal into a helper

[Prashant Rahul]

Factor out the common device removal sequence into a helper in
preparation for adding cleanup to the probe error path.

Signed-off-by: Prashant Rahul <prashantrahul23@gmail.com>
---
 drivers/staging/octeon/ethernet.c | 27 ++++++++++++++++-----------
 1 file changed, 16 insertions(+), 11 deletions(-)

diff --git a/drivers/staging/octeon/ethernet.c b/drivers/staging/octeon/ethernet.c
index f3fa221f452e2..e07c6911b8252 100644
--- a/drivers/staging/octeon/ethernet.c
+++ b/drivers/staging/octeon/ethernet.c
@@ -104,6 +104,21 @@ struct net_device *cvm_oct_device[TOTAL_NUMBER_OF_PORTS];
 
 u64 cvm_oct_tx_poll_interval;
 
+static inline void cvm_oct_remove_device(int port)
+{
+	if (cvm_oct_device[port]) {
+		struct net_device *dev = cvm_oct_device[port];
+		struct octeon_ethernet *priv = netdev_priv(dev);
+
+		cancel_delayed_work_sync(&priv->port_periodic_work);
+
+		cvm_oct_tx_shutdown_dev(dev);
+		unregister_netdev(dev);
+		free_netdev(dev);
+		cvm_oct_device[port] = NULL;
+	}
+}
+
 static void cvm_oct_rx_refill_worker(struct work_struct *work)
 {
 	struct octeon_ethernet_platform *plat = container_of(work,
@@ -949,17 +964,7 @@ static void cvm_oct_remove(struct platform_device *pdev)
 
 	/* Free the ethernet devices */
 	for (port = 0; port < TOTAL_NUMBER_OF_PORTS; port++) {
-		if (cvm_oct_device[port]) {
-			struct net_device *dev = cvm_oct_device[port];
-			struct octeon_ethernet *priv = netdev_priv(dev);
-
-			cancel_delayed_work_sync(&priv->port_periodic_work);
-
-			cvm_oct_tx_shutdown_dev(dev);
-			unregister_netdev(dev);
-			free_netdev(dev);
-			cvm_oct_device[port] = NULL;
-		}
+		cvm_oct_remove_device(port);
 	}
 
 	cvmx_pko_shutdown();

-- 
2.54.0

[PATCH 2/4] staging: octeon: Propagate rx initialization failures

[Prashant Rahul]

Instead of calling panic(), log and propagate the error upwards for
better error handling.

Signed-off-by: Prashant Rahul <prashantrahul23@gmail.com>
---
 drivers/staging/octeon/ethernet-rx.c | 18 ++++++++++++------
 drivers/staging/octeon/ethernet-rx.h |  2 +-
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/staging/octeon/ethernet-rx.c b/drivers/staging/octeon/ethernet-rx.c
index cd36b5ba6f6c2..66e7253d484de 100644
--- a/drivers/staging/octeon/ethernet-rx.c
+++ b/drivers/staging/octeon/ethernet-rx.c
@@ -5,6 +5,8 @@
  * Copyright (c) 2003-2010 Cavium Networks
  */
 
+#include <asm-generic/errno-base.h>
+#include <linux/dev_printk.h>
 #include <linux/platform_device.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
@@ -445,22 +447,24 @@ void cvm_oct_poll_controller(struct net_device *dev)
 }
 #endif
 
-void cvm_oct_rx_initialize(struct platform_device *pdev)
+int cvm_oct_rx_initialize(struct platform_device *pdev)
 {
 	int i;
 	struct net_device *dev_for_napi = NULL;
 	struct octeon_ethernet_platform *plat = platform_get_drvdata(pdev);
 	struct oct_rx_group *rx_group = plat->rx_group;
 
 	for (i = 0; i < TOTAL_NUMBER_OF_PORTS; i++) {
 		if (cvm_oct_device[i]) {
 			dev_for_napi = cvm_oct_device[i];
 			break;
 		}
 	}
 
-	if (!dev_for_napi)
-		panic("No net_devices were allocated.");
+	if (!dev_for_napi) {
+		dev_err(&pdev->dev, "No net_devices were allocated.");
+		return -ENODEV;
+	}
 
 	for (i = 0; i < ARRAY_SIZE(plat->rx_group); i++) {
 		int ret;
@@ -479,9 +483,10 @@ void cvm_oct_rx_initialize(struct platform_device *pdev)
 		/* Register an IRQ handler to receive POW interrupts */
 		ret = request_irq(rx_group[i].irq, cvm_oct_do_interrupt, 0,
 				  "Ethernet", &rx_group[i].napi);
-		if (ret)
-			panic("Could not acquire Ethernet IRQ %d\n",
-			      rx_group[i].irq);
+		if (ret) {
+			dev_err(&pdev->dev, "Could not acquire Ethernet IRQ %d\n", rx_group[i].irq);
+			return ret;
+		}
 
 		disable_irq_nosync(rx_group[i].irq);
 
@@ -518,6 +523,7 @@ void cvm_oct_rx_initialize(struct platform_device *pdev)
 		napi_schedule(&rx_group[i].napi);
 	}
 	atomic_inc(&oct_rx_ready);
+	return 0;
 }
 
 void cvm_oct_rx_shutdown(struct platform_device *pdev)
diff --git a/drivers/staging/octeon/ethernet-rx.h b/drivers/staging/octeon/ethernet-rx.h
index 6093694326cb6..ff3ed3d784a4b 100644
--- a/drivers/staging/octeon/ethernet-rx.h
+++ b/drivers/staging/octeon/ethernet-rx.h
@@ -8,7 +8,7 @@
 struct platform_device;
 
 void cvm_oct_poll_controller(struct net_device *dev);
-void cvm_oct_rx_initialize(struct platform_device *pdev);
+int cvm_oct_rx_initialize(struct platform_device *pdev);
 void cvm_oct_rx_shutdown(struct platform_device *pdev);
 
 static inline void cvm_oct_rx_refill_pool(struct platform_device *pdev,

-- 
2.54.0

[PATCH 3/4] staging: octeon: Propagate tx initialization failures

[Prashant Rahul]

Instead of calling panic(), log and propagate the error upwards for
better error handling.

Pass platform_device to tx initializer to match the rx
initializer interface and to log device specific failures.

Signed-off-by: Prashant Rahul <prashantrahul23@gmail.com>
---
 drivers/staging/octeon/ethernet-tx.c | 17 +++++++++--------
 drivers/staging/octeon/ethernet-tx.h |  2 +-
 drivers/staging/octeon/ethernet.c    |  2 +-
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/octeon/ethernet-tx.c b/drivers/staging/octeon/ethernet-tx.c
index 14d10659bce71..0f3b1f34ff2a3 100644
--- a/drivers/staging/octeon/ethernet-tx.c
+++ b/drivers/staging/octeon/ethernet-tx.c
@@ -5,6 +5,7 @@
  * Copyright (c) 2003-2010 Cavium Networks
  */
 
+#include <linux/platform_device.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/netdevice.h>
@@ -649,19 +650,19 @@ static irqreturn_t cvm_oct_tx_cleanup_watchdog(int cpl, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-void cvm_oct_tx_initialize(void)
+int cvm_oct_tx_initialize(struct platform_device *pdev)
 {
-	int i;
+	int ret;
 
 	/* Disable the interrupt.  */
 	cvmx_write_csr(CVMX_CIU_TIMX(1), 0);
 	/* Register an IRQ handler to receive CIU_TIMX(1) interrupts */
-	i = request_irq(OCTEON_IRQ_TIMER1,
-			cvm_oct_tx_cleanup_watchdog, 0,
-			"Ethernet", cvm_oct_device);
-
-	if (i)
-		panic("Could not acquire Ethernet IRQ %d\n", OCTEON_IRQ_TIMER1);
+	ret = request_irq(OCTEON_IRQ_TIMER1, cvm_oct_tx_cleanup_watchdog, 0,
+			  "Ethernet", cvm_oct_device);
+	if (ret)
+		dev_warn(&pdev->dev, "Could not acquire Ethernet IRQ %d\n",
+			 OCTEON_IRQ_TIMER1);
+	return ret;
 }
 
 void cvm_oct_tx_shutdown(void)
diff --git a/drivers/staging/octeon/ethernet-tx.h b/drivers/staging/octeon/ethernet-tx.h
index 6c524668f65a5..b03d56b0d2b65 100644
--- a/drivers/staging/octeon/ethernet-tx.h
+++ b/drivers/staging/octeon/ethernet-tx.h
@@ -9,6 +9,6 @@ netdev_tx_t cvm_oct_xmit(struct sk_buff *skb, struct net_device *dev);
 netdev_tx_t cvm_oct_xmit_pow(struct sk_buff *skb, struct net_device *dev);
 int cvm_oct_transmit_qos(struct net_device *dev, void *work_queue_entry,
 			 int do_free, int qos);
-void cvm_oct_tx_initialize(void);
+int cvm_oct_tx_initialize(struct platform_device *pdev);
 void cvm_oct_tx_shutdown(void);
 void cvm_oct_tx_shutdown_dev(struct net_device *dev);
diff --git a/drivers/staging/octeon/ethernet.c b/drivers/staging/octeon/ethernet.c
index e07c6911b8252..1d3bf3c79598d 100644
--- a/drivers/staging/octeon/ethernet.c
+++ b/drivers/staging/octeon/ethernet.c
@@ -934,7 +934,7 @@ static int cvm_oct_probe(struct platform_device *pdev)
 		}
 	}
 
-	cvm_oct_tx_initialize();
+	cvm_oct_tx_initialize(pdev);
 	cvm_oct_rx_initialize(pdev);
 
 	/*

-- 
2.54.0

[PATCH 4/4] staging: octeon: handle rx/tx initialization failures in probe

[Prashant Rahul]

Check return value of rx/tx initialization functions and abort probing
if either one fails.

Add error handling labels to deallocate resources before returning the
error.

Signed-off-by: Prashant Rahul <prashantrahul23@gmail.com>
---
 drivers/staging/octeon/ethernet.c | 38 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 36 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/octeon/ethernet.c b/drivers/staging/octeon/ethernet.c
index 1d3bf3c79598d..41be73b2ded91 100644
--- a/drivers/staging/octeon/ethernet.c
+++ b/drivers/staging/octeon/ethernet.c
@@ -688,6 +688,7 @@ static int cvm_oct_probe(struct platform_device *pdev)
 {
 	int num_interfaces;
 	int interface;
+	int ret = 0;
 	int fau = FAU_NUM_PACKET_BUFFERS_TO_FREE;
 	int qos;
 	struct device_node *pip;
@@ -934,17 +935,50 @@ static int cvm_oct_probe(struct platform_device *pdev)
 		}
 	}
 
-	cvm_oct_tx_initialize(pdev);
-	cvm_oct_rx_initialize(pdev);
+	ret = cvm_oct_tx_initialize(pdev);
+	if (ret)
+		goto err_tx;
+
+	ret = cvm_oct_rx_initialize(pdev);
+	if (ret)
+		goto err_rx;
 
 	/*
 	 * 150 uS: about 10 1500-byte packets at 1GE.
 	 */
 	cvm_oct_tx_poll_interval = 150 * (octeon_get_clock_rate() / 1000000);
 
 	schedule_delayed_work(&plat->rx_refill_work, HZ);
 
 	return 0;
+
+err_rx:
+	cvm_oct_tx_shutdown();
+err_tx:
+	cvmx_ipd_disable();
+
+	atomic_inc_return(&cvm_oct_poll_queue_stopping);
+
+	cvmx_pko_disable();
+
+	/* Free the ethernet devices */
+	for (int port = 0; port < TOTAL_NUMBER_OF_PORTS; port++)
+		cvm_oct_remove_device(port);
+
+	cvmx_pko_shutdown();
+
+	cvmx_ipd_free_ptr();
+
+	/* Free the HW pools */
+	cvm_oct_mem_empty_fpa(pdev, CVMX_FPA_PACKET_POOL, CVMX_FPA_PACKET_POOL_SIZE,
+			      num_packet_buffers);
+	cvm_oct_mem_empty_fpa(pdev, CVMX_FPA_WQE_POOL, CVMX_FPA_WQE_POOL_SIZE,
+			      num_packet_buffers);
+	if (CVMX_FPA_OUTPUT_BUFFER_POOL != CVMX_FPA_PACKET_POOL)
+		cvm_oct_mem_empty_fpa(pdev, CVMX_FPA_OUTPUT_BUFFER_POOL,
+				      CVMX_FPA_OUTPUT_BUFFER_POOL_SIZE, 128);
+
+	return ret;
 }
 
 static void cvm_oct_remove(struct platform_device *pdev)

-- 
2.54.0

Re: [PATCH 0/4] staging: octeon: Improve initialization error handling

[Dan Carpenter]

On Sun, Jun 28, 2026 at 12:31:23PM +0530, Prashant Rahul wrote:
> Hi all,
> 
> The TX and RX initialization paths currently call panic() on some
> initialization failures. Instead, these failures should be reported back
> to the probe function so that it can unwind any resources acquired during
> initialization and fail gracefully.
> 
> This series replaces those panic() calls with proper error logging, propagates
> the errors to the probe function, and adds the necessary cleanup to avoid
> leaving the driver in a partially initialized state.
> 
> This is my first time working with drivers, so please let me know if I
> have made any mistakes.
> 
> Thank you! :3
> 
> Signed-off-by: Prashant Rahul <prashantrahul23@gmail.com>
> ---

You need to say when you haven't tested your code.

You need to say when you're using AI to write patches.  There is
a format for it.
Documentation/process/coding-assistants.rst

regards,
dan carpenter

Re: [PATCH 1/4] staging: octeon: factor out device removal into a helper

[Dan Carpenter]

On Sun, Jun 28, 2026 at 12:31:24PM +0530, Prashant Rahul wrote:
> Factor out the common device removal sequence into a helper in
> preparation for adding cleanup to the probe error path.
> 
> Signed-off-by: Prashant Rahul <prashantrahul23@gmail.com>
> ---
>  drivers/staging/octeon/ethernet.c | 27 ++++++++++++++++-----------
>  1 file changed, 16 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/staging/octeon/ethernet.c b/drivers/staging/octeon/ethernet.c
> index f3fa221f452e2..e07c6911b8252 100644
> --- a/drivers/staging/octeon/ethernet.c
> +++ b/drivers/staging/octeon/ethernet.c
> @@ -104,6 +104,21 @@ struct net_device *cvm_oct_device[TOTAL_NUMBER_OF_PORTS];
>  
>  u64 cvm_oct_tx_poll_interval;
>  
> +static inline void cvm_oct_remove_device(int port)
> +{
> +	if (cvm_oct_device[port]) {
> +		struct net_device *dev = cvm_oct_device[port];
> +		struct octeon_ethernet *priv = netdev_priv(dev);
> +
> +		cancel_delayed_work_sync(&priv->port_periodic_work);
> +
> +		cvm_oct_tx_shutdown_dev(dev);
> +		unregister_netdev(dev);
> +		free_netdev(dev);
> +		cvm_oct_device[port] = NULL;
> +	}
> +}
> +
>  static void cvm_oct_rx_refill_worker(struct work_struct *work)
>  {
>  	struct octeon_ethernet_platform *plat = container_of(work,
> @@ -949,17 +964,7 @@ static void cvm_oct_remove(struct platform_device *pdev)
>  
>  	/* Free the ethernet devices */
>  	for (port = 0; port < TOTAL_NUMBER_OF_PORTS; port++) {
> -		if (cvm_oct_device[port]) {
> -			struct net_device *dev = cvm_oct_device[port];
> -			struct octeon_ethernet *priv = netdev_priv(dev);
> -
> -			cancel_delayed_work_sync(&priv->port_periodic_work);
> -
> -			cvm_oct_tx_shutdown_dev(dev);
> -			unregister_netdev(dev);
> -			free_netdev(dev);
> -			cvm_oct_device[port] = NULL;
> -		}
> +		cvm_oct_remove_device(port);
>  	}

Delete the curly braces as well.

regards,
dan carpenter

Re: [PATCH 4/4] staging: octeon: handle rx/tx initialization failures in probe

[Dan Carpenter]

On Sun, Jun 28, 2026 at 12:31:27PM +0530, Prashant Rahul wrote:
> Check return value of rx/tx initialization functions and abort probing
> if either one fails.
> 
> Add error handling labels to deallocate resources before returning the
> error.
> 
> Signed-off-by: Prashant Rahul <prashantrahul23@gmail.com>
> ---
>  drivers/staging/octeon/ethernet.c | 38 ++++++++++++++++++++++++++++++++++++--
>  1 file changed, 36 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/octeon/ethernet.c b/drivers/staging/octeon/ethernet.c
> index 1d3bf3c79598d..41be73b2ded91 100644
> --- a/drivers/staging/octeon/ethernet.c
> +++ b/drivers/staging/octeon/ethernet.c
> @@ -688,6 +688,7 @@ static int cvm_oct_probe(struct platform_device *pdev)
>  {
>  	int num_interfaces;
>  	int interface;
> +	int ret = 0;
>  	int fau = FAU_NUM_PACKET_BUFFERS_TO_FREE;
>  	int qos;
>  	struct device_node *pip;
> @@ -934,17 +935,50 @@ static int cvm_oct_probe(struct platform_device *pdev)
>  		}
>  	}
>  
> -	cvm_oct_tx_initialize(pdev);
> -	cvm_oct_rx_initialize(pdev);
> +	ret = cvm_oct_tx_initialize(pdev);
> +	if (ret)
> +		goto err_tx;
> +
> +	ret = cvm_oct_rx_initialize(pdev);
> +	if (ret)
> +		goto err_rx;
>  
>  	/*
>  	 * 150 uS: about 10 1500-byte packets at 1GE.
>  	 */
>  	cvm_oct_tx_poll_interval = 150 * (octeon_get_clock_rate() / 1000000);
>  
>  	schedule_delayed_work(&plat->rx_refill_work, HZ);
>  
>  	return 0;
> +
> +err_rx:
> +	cvm_oct_tx_shutdown();
> +err_tx:
> +	cvmx_ipd_disable();
> +
> +	atomic_inc_return(&cvm_oct_poll_queue_stopping);
> +
> +	cvmx_pko_disable();
> +
> +	/* Free the ethernet devices */
> +	for (int port = 0; port < TOTAL_NUMBER_OF_PORTS; port++)
> +		cvm_oct_remove_device(port);
> +
> +	cvmx_pko_shutdown();

This is all copied from the shutdown and it looks basically
reasonable to me.  This is staging code so of course it's a
bit wonky.  cvmx_pko_shutdown() has a built in call to
cvmx_pko_disable() so why are we calling that separately?

Also I feel like probe() should fail if alloc_netdev() fails
or register_netdev(), but that's not introduced by this patch
either.  And I have no way to test this.  Even reviewing MIPS
code is a pain in the behind because I don't have the cross
compiler set up.

Reviewed-by: Dan Carpenter <error27@gmail.com>

regards,
dan carpenter

Re: [PATCH 1/4] staging: octeon: factor out device removal into a helper

[Dan Carpenter]

On Sun, Jun 28, 2026 at 12:31:24PM +0530, Prashant Rahul wrote:
> Factor out the common device removal sequence into a helper in
> preparation for adding cleanup to the probe error path.
> 
> Signed-off-by: Prashant Rahul <prashantrahul23@gmail.com>
> ---
>  drivers/staging/octeon/ethernet.c | 27 ++++++++++++++++-----------
>  1 file changed, 16 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/staging/octeon/ethernet.c b/drivers/staging/octeon/ethernet.c
> index f3fa221f452e2..e07c6911b8252 100644
> --- a/drivers/staging/octeon/ethernet.c
> +++ b/drivers/staging/octeon/ethernet.c
> @@ -104,6 +104,21 @@ struct net_device *cvm_oct_device[TOTAL_NUMBER_OF_PORTS];
>  
>  u64 cvm_oct_tx_poll_interval;
>  
> +static inline void cvm_oct_remove_device(int port)

It's a minor thing, but don't mark functions as inline.  The compiler
just ignores it anyway so it's just noise.

regards,
dan carpenter

Re: [PATCH 0/4] staging: octeon: Improve initialization error handling

[Prashant Rahul]

On Mon Jun 29, 2026 at 12:54 PM IST, Dan Carpenter wrote:

> You need to say when you haven't tested your code.

will do, thank you!

> You need to say when you're using AI to write patches.  There is
> a format for it.
> Documentation/process/coding-assistants.rst

Thank you for pointing it out, however I have not used any AI assistant
for this patch series. I used Harper, an offline grammar checker, to
help me write the emails, do I need to specify that? Other than that I used
basic tools like an editor, make, git etc.

Re: [PATCH 0/4] staging: octeon: Improve initialization error handling

[Dan Carpenter]

On Mon, Jun 29, 2026 at 01:55:46PM +0530, Prashant Rahul wrote:
> On Mon Jun 29, 2026 at 12:54 PM IST, Dan Carpenter wrote:
> 
> > You need to say when you haven't tested your code.
> 
> will do, thank you!
> 
> > You need to say when you're using AI to write patches.  There is
> > a format for it.
> > Documentation/process/coding-assistants.rst
> 
> Thank you for pointing it out, however I have not used any AI assistant
> for this patch series. I used Harper, an offline grammar checker, to
> help me write the emails, do I need to specify that? Other than that I used
> basic tools like an editor, make, git etc.

Ah, fine then.

regards,
dan carpenter