diff mbox series

gpiolib: cdev: Set lineevent_state::irq after IRQ register successfully

Message ID 20220921032020.25398-1-Meng.Li@windriver.com
State New
Headers show
Series gpiolib: cdev: Set lineevent_state::irq after IRQ register successfully | expand

Commit Message

Meng Li Sept. 21, 2022, 3:20 a.m. UTC 
When running gpio test on nxp-ls1028 platform with below command
gpiomon --num-events=3 --rising-edge gpiochip1 25
There will be a warning trace as below:
Call trace:
free_irq+0x204/0x360
lineevent_free+0x64/0x70
gpio_ioctl+0x598/0x6a0
__arm64_sys_ioctl+0xb4/0x100
invoke_syscall+0x5c/0x130
......
el0t_64_sync+0x1a0/0x1a4
The reason of this issue is that calling request_threaded_irq()
function failed, and then lineevent_free() is invoked to release
the resource. Since the lineevent_state::irq was already set, so
the subsequent invocation of free_irq() would trigger the above
warning call trace. To fix this issue, set the lineevent_state::irq
after the IRQ register successfully.

Fixes: 468242724143 ("gpiolib: cdev: refactor lineevent cleanup into lineevent_free")
Cc: stable@vger.kernel.org
Signed-off-by: Meng Li <Meng.Li@windriver.com>
---
 drivers/gpio/gpiolib-cdev.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Comments

Kent Gibson Sept. 21, 2022, 3:52 a.m. UTC | #1 
On Wed, Sep 21, 2022 at 11:20:20AM +0800, Meng Li wrote:
> When running gpio test on nxp-ls1028 platform with below command
> gpiomon --num-events=3 --rising-edge gpiochip1 25
> There will be a warning trace as below:
> Call trace:
> free_irq+0x204/0x360
> lineevent_free+0x64/0x70
> gpio_ioctl+0x598/0x6a0
> __arm64_sys_ioctl+0xb4/0x100
> invoke_syscall+0x5c/0x130
> ......
> el0t_64_sync+0x1a0/0x1a4
> The reason of this issue is that calling request_threaded_irq()
> function failed, and then lineevent_free() is invoked to release
> the resource. Since the lineevent_state::irq was already set, so
> the subsequent invocation of free_irq() would trigger the above
> warning call trace. To fix this issue, set the lineevent_state::irq
> after the IRQ register successfully.
> 
> Fixes: 468242724143 ("gpiolib: cdev: refactor lineevent cleanup into lineevent_free")
> Cc: stable@vger.kernel.org
> Signed-off-by: Meng Li <Meng.Li@windriver.com>

Good pick up - the IRQ shouldn't be freed if it hasn't been successfully requested.

Signed-off-by: Kent Gibson <warthog618@gmail.com>

> ---
>  drivers/gpio/gpiolib-cdev.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
> index ffa0256cad5a..937e7a8dd8a9 100644
> --- a/drivers/gpio/gpiolib-cdev.c
> +++ b/drivers/gpio/gpiolib-cdev.c
> @@ -1784,7 +1784,6 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
>  		ret = -ENODEV;
>  		goto out_free_le;
>  	}
> -	le->irq = irq;
>  
>  	if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
>  		irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
> @@ -1798,7 +1797,7 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
>  	init_waitqueue_head(&le->wait);
>  
>  	/* Request a thread to read the events */
> -	ret = request_threaded_irq(le->irq,
> +	ret = request_threaded_irq(irq,
>  				   lineevent_irq_handler,
>  				   lineevent_irq_thread,
>  				   irqflags,
> @@ -1807,6 +1806,8 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
>  	if (ret)
>  		goto out_free_le;
>  
> +	le->irq = irq;
> +
>  	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
>  	if (fd < 0) {
>  		ret = fd;
> -- 
> 2.36.1
>
Kent Gibson Sept. 21, 2022, 6:40 a.m. UTC | #2 
On Wed, Sep 21, 2022 at 11:52:31AM +0800, Kent Gibson wrote:
> On Wed, Sep 21, 2022 at 11:20:20AM +0800, Meng Li wrote:
> > When running gpio test on nxp-ls1028 platform with below command
> > gpiomon --num-events=3 --rising-edge gpiochip1 25
> > There will be a warning trace as below:
> > Call trace:
> > free_irq+0x204/0x360
> > lineevent_free+0x64/0x70
> > gpio_ioctl+0x598/0x6a0
> > __arm64_sys_ioctl+0xb4/0x100
> > invoke_syscall+0x5c/0x130
> > ......
> > el0t_64_sync+0x1a0/0x1a4
> > The reason of this issue is that calling request_threaded_irq()
> > function failed, and then lineevent_free() is invoked to release
> > the resource. Since the lineevent_state::irq was already set, so
> > the subsequent invocation of free_irq() would trigger the above
> > warning call trace. To fix this issue, set the lineevent_state::irq
> > after the IRQ register successfully.
> > 
> > Fixes: 468242724143 ("gpiolib: cdev: refactor lineevent cleanup into lineevent_free")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Meng Li <Meng.Li@windriver.com>
> 
> Good pick up - the IRQ shouldn't be freed if it hasn't been successfully requested.
> 
> Signed-off-by: Kent Gibson <warthog618@gmail.com>
> 

Oops, that should be

Reviewed-by: Kent Gibson <warthog618@gmail.com>
Bartosz Golaszewski Sept. 21, 2022, 7:33 a.m. UTC | #3 
On Wed, Sep 21, 2022 at 5:23 AM Meng Li <Meng.Li@windriver.com> wrote:
>
> When running gpio test on nxp-ls1028 platform with below command
> gpiomon --num-events=3 --rising-edge gpiochip1 25
> There will be a warning trace as below:
> Call trace:
> free_irq+0x204/0x360
> lineevent_free+0x64/0x70
> gpio_ioctl+0x598/0x6a0
> __arm64_sys_ioctl+0xb4/0x100
> invoke_syscall+0x5c/0x130
> ......
> el0t_64_sync+0x1a0/0x1a4
> The reason of this issue is that calling request_threaded_irq()
> function failed, and then lineevent_free() is invoked to release
> the resource. Since the lineevent_state::irq was already set, so
> the subsequent invocation of free_irq() would trigger the above
> warning call trace. To fix this issue, set the lineevent_state::irq
> after the IRQ register successfully.
>
> Fixes: 468242724143 ("gpiolib: cdev: refactor lineevent cleanup into lineevent_free")
> Cc: stable@vger.kernel.org
> Signed-off-by: Meng Li <Meng.Li@windriver.com>
> ---
>  drivers/gpio/gpiolib-cdev.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
> index ffa0256cad5a..937e7a8dd8a9 100644
> --- a/drivers/gpio/gpiolib-cdev.c
> +++ b/drivers/gpio/gpiolib-cdev.c
> @@ -1784,7 +1784,6 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
>                 ret = -ENODEV;
>                 goto out_free_le;
>         }
> -       le->irq = irq;
>
>         if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
>                 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
> @@ -1798,7 +1797,7 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
>         init_waitqueue_head(&le->wait);
>
>         /* Request a thread to read the events */
> -       ret = request_threaded_irq(le->irq,
> +       ret = request_threaded_irq(irq,
>                                    lineevent_irq_handler,
>                                    lineevent_irq_thread,
>                                    irqflags,
> @@ -1807,6 +1806,8 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
>         if (ret)
>                 goto out_free_le;
>
> +       le->irq = irq;
> +
>         fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
>         if (fd < 0) {
>                 ret = fd;
> --
> 2.36.1
>

Applied, thanks!

Bart
diff mbox series

Patch

diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index ffa0256cad5a..937e7a8dd8a9 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -1784,7 +1784,6 @@  static int lineevent_create(struct gpio_device *gdev, void __user *ip)
 		ret = -ENODEV;
 		goto out_free_le;
 	}
-	le->irq = irq;
 
 	if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
 		irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
@@ -1798,7 +1797,7 @@  static int lineevent_create(struct gpio_device *gdev, void __user *ip)
 	init_waitqueue_head(&le->wait);
 
 	/* Request a thread to read the events */
-	ret = request_threaded_irq(le->irq,
+	ret = request_threaded_irq(irq,
 				   lineevent_irq_handler,
 				   lineevent_irq_thread,
 				   irqflags,
@@ -1807,6 +1806,8 @@  static int lineevent_create(struct gpio_device *gdev, void __user *ip)
 	if (ret)
 		goto out_free_le;
 
+	le->irq = irq;
+
 	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
 	if (fd < 0) {
 		ret = fd;