* [PATCH] can: mcp251x: Fix resume from sleep before interface was brought up
@ 2021-05-04 16:01 Schrempf Frieder
2021-05-04 16:24 ` Andy Shevchenko
2021-05-04 18:48 ` Marc Kleine-Budde
0 siblings, 2 replies; 4+ messages in thread
From: Schrempf Frieder @ 2021-05-04 16:01 UTC (permalink / raw)
To: Marc Kleine-Budde, Vincent Mailhol, Oliver Hartkopp,
Frieder Schrempf, Gustavo A. R. Silva, Timo Schlüßler,
Andy Shevchenko, Tim Harvey
Cc: stable, linux-can, netdev, linux-kernel
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>
---
drivers/net/can/spi/mcp251x.c | 25 ++++++++++++++-----------
1 file changed, 14 insertions(+), 11 deletions(-)
diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c
index a57da43680d8..42e8e5791c9f 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;
@@ -1373,6 +1362,15 @@ 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 +1415,8 @@ 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 +1438,9 @@ 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);
--
2.25.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] can: mcp251x: Fix resume from sleep before interface was brought up
2021-05-04 16:01 [PATCH] can: mcp251x: Fix resume from sleep before interface was brought up Schrempf Frieder
@ 2021-05-04 16:24 ` Andy Shevchenko
2021-05-04 18:48 ` Marc Kleine-Budde
1 sibling, 0 replies; 4+ messages in thread
From: Andy Shevchenko @ 2021-05-04 16:24 UTC (permalink / raw)
To: Schrempf Frieder
Cc: Marc Kleine-Budde, Vincent Mailhol, Oliver Hartkopp,
Gustavo A. R. Silva, Timo Schlüßler, Tim Harvey,
stable, linux-can, netdev, linux-kernel
On Tue, May 04, 2021 at 06:01:48PM +0200, Schrempf Frieder wrote:
> 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.
AFAIU the IRQ is freed at ->ndo_stop() which is guaranteed to be called before
->remove(). If it's the case, we are fine.
FWIW,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Fixes: 8ce8c0abcba3 ("can: mcp251x: only reset hardware as required")
> Cc: stable@vger.kernel.org
> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
> ---
> drivers/net/can/spi/mcp251x.c | 25 ++++++++++++++-----------
> 1 file changed, 14 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c
> index a57da43680d8..42e8e5791c9f 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;
> @@ -1373,6 +1362,15 @@ 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 +1415,8 @@ 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 +1438,9 @@ 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);
> --
> 2.25.1
>
>
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] can: mcp251x: Fix resume from sleep before interface was brought up
2021-05-04 16:01 [PATCH] can: mcp251x: Fix resume from sleep before interface was brought up Schrempf Frieder
2021-05-04 16:24 ` Andy Shevchenko
@ 2021-05-04 18:48 ` Marc Kleine-Budde
2021-05-04 19:40 ` Schlüßler, Timo
1 sibling, 1 reply; 4+ messages in thread
From: Marc Kleine-Budde @ 2021-05-04 18:48 UTC (permalink / raw)
To: Schrempf Frieder
Cc: Vincent Mailhol, Oliver Hartkopp, Gustavo A. R. Silva,
Timo Schlüßler, Andy Shevchenko, Tim Harvey, stable,
linux-can, netdev, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 966 bytes --]
On 04.05.2021 18:01:48, Schrempf Frieder wrote:
> 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>
Added to linux-can/testing.
Thanks,
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Embedded Linux | https://www.pengutronix.de |
Vertretung West/Dortmund | Phone: +49-231-2826-924 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] can: mcp251x: Fix resume from sleep before interface was brought up
2021-05-04 18:48 ` Marc Kleine-Budde
@ 2021-05-04 19:40 ` Schlüßler, Timo
0 siblings, 0 replies; 4+ messages in thread
From: Schlüßler, Timo @ 2021-05-04 19:40 UTC (permalink / raw)
To: Marc Kleine-Budde
Cc: Schrempf Frieder, Vincent Mailhol, Oliver Hartkopp,
Gustavo A. R. Silva, Andy Shevchenko, Tim Harvey, stable,
linux-can, netdev, linux-kernel
> On 04.05.2021 18:01:48, Schrempf Frieder wrote:
>> Fixes: 8ce8c0abcba3 ("can: mcp251x: only reset hardware as required")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Thanks for finding and fixing this and sorry for introducing the bug.
Regards
Timo
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-05-04 19:46 UTC | newest]
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2021-05-04 16:01 [PATCH] can: mcp251x: Fix resume from sleep before interface was brought up Schrempf Frieder
2021-05-04 16:24 ` Andy Shevchenko
2021-05-04 18:48 ` Marc Kleine-Budde
2021-05-04 19:40 ` Schlüßler, Timo
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