diff mbox series

[v2] can: mcp251x: Fix resume from sleep before interface was brought up

Message ID 17d5d714-b468-482f-f37a-482e3d6df84e@kontron.de
State Accepted
Commit 03c427147b2d3e503af258711af4fc792b89b0af
Headers show
Series [v2] can: mcp251x: Fix resume from sleep before interface was brought up | expand

Commit Message

Frieder Schrempf May 5, 2021, 7:14 a.m. UTC 
From: Frieder Schrempf <frieder.schrempf@kontron.de>

Since 8ce8c0abcba3 the driver queues work via priv->restart_work when
resuming after suspend, even when the interface was not previously
enabled. This causes a null dereference error as the workqueue is
only allocated and initialized in mcp251x_open().

To fix this we move the workqueue init to mcp251x_can_probe() as
there is no reason to do it later and repeat it whenever
mcp251x_open() is called.

Fixes: 8ce8c0abcba3 ("can: mcp251x: only reset hardware as required")
Cc: stable@vger.kernel.org
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
Changes in v2:
  * Remove the out_clean label in mcp251x_open()
  * Add Andy's R-b tag
  * Add 'From' tag

Hi Marc, I'm sending a v2 mainly because I noticed that v1 is missing
the 'From' tag and as my company's mailserver always sends my name
reversed this causes incorrect author information in git. So if possible
you could fix this up. If this is too much work, just leave it as is.
Thanks! 
---
 drivers/net/can/spi/mcp251x.c | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

Comments

Marc Kleine-Budde May 5, 2021, 7:51 a.m. UTC | #1 
On 05.05.2021 09:14:15, Frieder Schrempf wrote:
> From: Frieder Schrempf <frieder.schrempf@kontron.de>
> 
> Since 8ce8c0abcba3 the driver queues work via priv->restart_work when
> resuming after suspend, even when the interface was not previously
> enabled. This causes a null dereference error as the workqueue is
> only allocated and initialized in mcp251x_open().
> 
> To fix this we move the workqueue init to mcp251x_can_probe() as
> there is no reason to do it later and repeat it whenever
> mcp251x_open() is called.
> 
> Fixes: 8ce8c0abcba3 ("can: mcp251x: only reset hardware as required")
> Cc: stable@vger.kernel.org
> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> Changes in v2:
>   * Remove the out_clean label in mcp251x_open()
>   * Add Andy's R-b tag
>   * Add 'From' tag
> 
> Hi Marc, I'm sending a v2 mainly because I noticed that v1 is missing
> the 'From' tag and as my company's mailserver always sends my name
> reversed this causes incorrect author information in git. So if possible
> you could fix this up. If this is too much work, just leave it as is.
> Thanks!

Done.

I've also squashed this fixup:

| --- a/drivers/net/can/spi/mcp251x.c
| +++ b/drivers/net/can/spi/mcp251x.c
| @@ -1224,13 +1224,13 @@ static int mcp251x_open(struct net_device *net)
|  
|         ret = mcp251x_hw_wake(spi);
|         if (ret)
| -               goto out_free_wq;
| +               goto out_free_irq;
|         ret = mcp251x_setup(net, spi);
|         if (ret)
| -               goto out_free_wq;
| +               goto out_free_irq;
|         ret = mcp251x_set_normal_mode(spi);
|         if (ret)
| -               goto out_free_wq;
| +               goto out_free_irq;
|  
|         can_led_event(net, CAN_LED_EVENT_OPEN);
|  
| @@ -1239,8 +1239,7 @@ static int mcp251x_open(struct net_device *net)
|  
|         return 0;
|  
| -out_free_wq:
| -       destroy_workqueue(priv->wq);
| +out_free_irq:
|         free_irq(spi->irq, priv);
|         mcp251x_hw_sleep(spi);
|  out_close:

Marc
diff mbox series

Patch

diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c
index a57da43680d8..6f888b771589 100644
--- a/drivers/net/can/spi/mcp251x.c
+++ b/drivers/net/can/spi/mcp251x.c
@@ -956,8 +956,6 @@  static int mcp251x_stop(struct net_device *net)
 
 	priv->force_quit = 1;
 	free_irq(spi->irq, priv);
-	destroy_workqueue(priv->wq);
-	priv->wq = NULL;
 
 	mutex_lock(&priv->mcp_lock);
 
@@ -1224,15 +1222,6 @@  static int mcp251x_open(struct net_device *net)
 		goto out_close;
 	}
 
-	priv->wq = alloc_workqueue("mcp251x_wq", WQ_FREEZABLE | WQ_MEM_RECLAIM,
-				   0);
-	if (!priv->wq) {
-		ret = -ENOMEM;
-		goto out_clean;
-	}
-	INIT_WORK(&priv->tx_work, mcp251x_tx_work_handler);
-	INIT_WORK(&priv->restart_work, mcp251x_restart_work_handler);
-
 	ret = mcp251x_hw_wake(spi);
 	if (ret)
 		goto out_free_wq;
@@ -1252,7 +1241,6 @@  static int mcp251x_open(struct net_device *net)
 
 out_free_wq:
 	destroy_workqueue(priv->wq);
-out_clean:
 	free_irq(spi->irq, priv);
 	mcp251x_hw_sleep(spi);
 out_close:
@@ -1373,6 +1361,15 @@  static int mcp251x_can_probe(struct spi_device *spi)
 	if (ret)
 		goto out_clk;
 
+	priv->wq = alloc_workqueue("mcp251x_wq", WQ_FREEZABLE | WQ_MEM_RECLAIM,
+				   0);
+	if (!priv->wq) {
+		ret = -ENOMEM;
+		goto out_clk;
+	}
+	INIT_WORK(&priv->tx_work, mcp251x_tx_work_handler);
+	INIT_WORK(&priv->restart_work, mcp251x_restart_work_handler);
+
 	priv->spi = spi;
 	mutex_init(&priv->mcp_lock);
 
@@ -1417,6 +1414,8 @@  static int mcp251x_can_probe(struct spi_device *spi)
 	return 0;
 
 error_probe:
+	destroy_workqueue(priv->wq);
+	priv->wq = NULL;
 	mcp251x_power_enable(priv->power, 0);
 
 out_clk:
@@ -1438,6 +1437,9 @@  static int mcp251x_can_remove(struct spi_device *spi)
 
 	mcp251x_power_enable(priv->power, 0);
 
+	destroy_workqueue(priv->wq);
+	priv->wq = NULL;
+
 	clk_disable_unprepare(priv->clk);
 
 	free_candev(net);