2020-06-30 13:53:10

by Lee Jones

Subject: [PATCH 10/10] gpio: gpio-mlxbf2.c: Provide __releases() annotation to stop confusing Sparse

Sparse cannot peer into other functions to see when and if locks are
acquired and released, thus it simply warns that a 'context imbalance'
is detected instead. Let's be kind to Sparse and let it know that
this behaviour is intentional.

drivers/gpio/gpio-mlxbf2.c:125:12: warning: context imbalance in 'mlxbf2_gpio_lock_acquire' - different lock contexts for basic block
drivers/gpio/gpio-mlxbf2.c:151:13: warning: context imbalance in 'mlxbf2_gpio_lock_release' - unexpected unlock

Cc: Asmaa Mnebhi <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
---
drivers/gpio/gpio-mlxbf2.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c
index 861a8d0a84be0..befa5e1099439 100644
--- a/drivers/gpio/gpio-mlxbf2.c
+++ b/drivers/gpio/gpio-mlxbf2.c
@@ -149,6 +149,8 @@ static int mlxbf2_gpio_lock_acquire(struct mlxbf2_gpio_context *gs)
* Release the YU arm_gpio_lock after changing the direction mode.
*/
static void mlxbf2_gpio_lock_release(struct mlxbf2_gpio_context *gs)
+ __releases(&gs->gc.bgpio_lock)
+ __releases(yu_arm_gpio_lock_param.lock)
{
writel(YU_ARM_GPIO_LOCK_RELEASE, yu_arm_gpio_lock_param.io);
spin_unlock(&gs->gc.bgpio_lock);
--
2.25.1

2020-06-30 14:20:36

by Asmaa Mnebhi

Subject: RE: [PATCH 10/10] gpio: gpio-mlxbf2.c: Provide __releases() annotation to stop confusing Sparse

Reviewed-by: Asmaa Mnebhi <[email protected]>

Thank you.

-----Original Message-----
From: Lee Jones <[email protected]>
Sent: Tuesday, June 30, 2020 9:34 AM
To: [email protected]; [email protected]
Cc: [email protected]; [email protected]; [email protected]; Lee Jones <[email protected]>; Asmaa Mnebhi <[email protected]>
Subject: [PATCH 10/10] gpio: gpio-mlxbf2.c: Provide __releases() annotation to stop confusing Sparse

Sparse cannot peer into other functions to see when and if locks are acquired and released, thus it simply warns that a 'context imbalance'
is detected instead. Let's be kind to Sparse and let it know that this behaviour is intentional.

drivers/gpio/gpio-mlxbf2.c:125:12: warning: context imbalance in 'mlxbf2_gpio_lock_acquire' - different lock contexts for basic block
drivers/gpio/gpio-mlxbf2.c:151:13: warning: context imbalance in 'mlxbf2_gpio_lock_release' - unexpected unlock

Cc: Asmaa Mnebhi <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
---
drivers/gpio/gpio-mlxbf2.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c index 861a8d0a84be0..befa5e1099439 100644
--- a/drivers/gpio/gpio-mlxbf2.c
+++ b/drivers/gpio/gpio-mlxbf2.c
@@ -149,6 +149,8 @@ static int mlxbf2_gpio_lock_acquire(struct mlxbf2_gpio_context *gs)
* Release the YU arm_gpio_lock after changing the direction mode.
*/
static void mlxbf2_gpio_lock_release(struct mlxbf2_gpio_context *gs)
+ __releases(&gs->gc.bgpio_lock)
+ __releases(yu_arm_gpio_lock_param.lock)
{
writel(YU_ARM_GPIO_LOCK_RELEASE, yu_arm_gpio_lock_param.io);
spin_unlock(&gs->gc.bgpio_lock);
--
2.25.1

2020-07-08 07:26:56

by Linus Walleij

Subject: Re: [PATCH 10/10] gpio: gpio-mlxbf2.c: Provide __releases() annotation to stop confusing Sparse

On Tue, Jun 30, 2020 at 3:34 PM Lee Jones <[email protected]> wrote:

> Sparse cannot peer into other functions to see when and if locks are
> acquired and released, thus it simply warns that a 'context imbalance'
> is detected instead. Let's be kind to Sparse and let it know that
> this behaviour is intentional.
>
> drivers/gpio/gpio-mlxbf2.c:125:12: warning: context imbalance in 'mlxbf2_gpio_lock_acquire' - different lock contexts for basic block
> drivers/gpio/gpio-mlxbf2.c:151:13: warning: context imbalance in 'mlxbf2_gpio_lock_release' - unexpected unlock
>
> Cc: Asmaa Mnebhi <[email protected]>
> Signed-off-by: Lee Jones <[email protected]>

Patch applied!

Yours,
Linus Walleij