* [PATCH v2] gpio: max732x: Fix irq-events handler
@ 2015-04-22 13:20 Semen Protsenko
2015-04-24 10:29 ` Grygorii Strashko
2015-05-06 13:09 ` Linus Walleij
0 siblings, 2 replies; 3+ messages in thread
From: Semen Protsenko @ 2015-04-22 13:20 UTC (permalink / raw)
To: Linus Walleij, Alexandre Courbot
Cc: linux-gpio, linux-kernel, Grygorii Strashko
MAX732X clears all pending interrupts on I2C read (when interrupts
register is being read). Driver doesn't need to send any ACKs when
interrupt was handled. So replace handle_edge_irq() with
handle_simple_irq().
Using handle_edge_irq() (w/o .irq_ack callback set) may lead to NULL
pointer dereference in some cases. E.g. this was observed on
hibernation process:
Unable to handle kernel NULL pointer dereference at virtual address 0
Backtrace:
(handle_edge_irq) from (resend_irqs)
(resend_irqs) from (tasklet_action)
(tasklet_action) from (__do_softirq)
(__do_softirq) from (run_ksoftirqd)
(run_ksoftirqd) from (smpboot_thread_fn)
(smpboot_thread_fn) from (kthread)
(kthread) from (ret_from_fork)
Signed-off-by: Semen Protsenko <semen.protsenko@globallogic.com>
---
drivers/gpio/gpio-max732x.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
index 1885e5c..86dc6b3 100644
--- a/drivers/gpio/gpio-max732x.c
+++ b/drivers/gpio/gpio-max732x.c
@@ -530,7 +530,7 @@ static int max732x_irq_setup(struct max732x_chip *chip,
ret = gpiochip_irqchip_add(&chip->gpio_chip,
&max732x_irq_chip,
irq_base,
- handle_edge_irq,
+ handle_simple_irq,
IRQ_TYPE_NONE);
if (ret) {
dev_err(&client->dev,
--
1.7.9.5
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v2] gpio: max732x: Fix irq-events handler
2015-04-22 13:20 [PATCH v2] gpio: max732x: Fix irq-events handler Semen Protsenko
@ 2015-04-24 10:29 ` Grygorii Strashko
2015-05-06 13:09 ` Linus Walleij
1 sibling, 0 replies; 3+ messages in thread
From: Grygorii Strashko @ 2015-04-24 10:29 UTC (permalink / raw)
To: Semen Protsenko, Linus Walleij, Alexandre Courbot
Cc: linux-gpio, linux-kernel, Grygorii Strashko
On 04/22/2015 04:20 PM, Semen Protsenko wrote:
> MAX732X clears all pending interrupts on I2C read (when interrupts
> register is being read). Driver doesn't need to send any ACKs when
> interrupt was handled. So replace handle_edge_irq() with
> handle_simple_irq().
>
> Using handle_edge_irq() (w/o .irq_ack callback set) may lead to NULL
> pointer dereference in some cases. E.g. this was observed on
> hibernation process:
>
> Unable to handle kernel NULL pointer dereference at virtual address 0
> Backtrace:
> (handle_edge_irq) from (resend_irqs)
> (resend_irqs) from (tasklet_action)
> (tasklet_action) from (__do_softirq)
> (__do_softirq) from (run_ksoftirqd)
> (run_ksoftirqd) from (smpboot_thread_fn)
> (smpboot_thread_fn) from (kthread)
> (kthread) from (ret_from_fork)
>
> Signed-off-by: Semen Protsenko <semen.protsenko@globallogic.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@linaro.org>
> ---
> drivers/gpio/gpio-max732x.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
> index 1885e5c..86dc6b3 100644
> --- a/drivers/gpio/gpio-max732x.c
> +++ b/drivers/gpio/gpio-max732x.c
> @@ -530,7 +530,7 @@ static int max732x_irq_setup(struct max732x_chip *chip,
> ret = gpiochip_irqchip_add(&chip->gpio_chip,
> &max732x_irq_chip,
> irq_base,
> - handle_edge_irq,
> + handle_simple_irq,
> IRQ_TYPE_NONE);
> if (ret) {
> dev_err(&client->dev,
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v2] gpio: max732x: Fix irq-events handler
2015-04-22 13:20 [PATCH v2] gpio: max732x: Fix irq-events handler Semen Protsenko
2015-04-24 10:29 ` Grygorii Strashko
@ 2015-05-06 13:09 ` Linus Walleij
1 sibling, 0 replies; 3+ messages in thread
From: Linus Walleij @ 2015-05-06 13:09 UTC (permalink / raw)
To: Semen Protsenko
Cc: Alexandre Courbot, linux-gpio, linux-kernel, Grygorii Strashko
On Wed, Apr 22, 2015 at 3:20 PM, Semen Protsenko
<semen.protsenko@globallogic.com> wrote:
> MAX732X clears all pending interrupts on I2C read (when interrupts
> register is being read). Driver doesn't need to send any ACKs when
> interrupt was handled. So replace handle_edge_irq() with
> handle_simple_irq().
>
> Using handle_edge_irq() (w/o .irq_ack callback set) may lead to NULL
> pointer dereference in some cases. E.g. this was observed on
> hibernation process:
>
> Unable to handle kernel NULL pointer dereference at virtual address 0
> Backtrace:
> (handle_edge_irq) from (resend_irqs)
> (resend_irqs) from (tasklet_action)
> (tasklet_action) from (__do_softirq)
> (__do_softirq) from (run_ksoftirqd)
> (run_ksoftirqd) from (smpboot_thread_fn)
> (smpboot_thread_fn) from (kthread)
> (kthread) from (ret_from_fork)
>
> Signed-off-by: Semen Protsenko <semen.protsenko@globallogic.com>
Patch applied with Grygorii's Review tag.
Yours,
Linus Walleij
^ permalink raw reply [flat|nested] 3+ messages in thread
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2015-04-24 10:29 ` Grygorii Strashko
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