My brain-damaged adjustments to Paul's patch caused crashes in
gpio_keys_disable_button() when driver is used in GPIO-less (i.e.
purely interrupt-driven) setups, because I mixed together debounce and
release timers when they are in fact separate:
Unable to handle kernel NULL pointer dereference at virtual address 0000000c
...
PC is at hrtimer_active+0xc/0x98
LR is at hrtimer_try_to_cancel+0x24/0x140
...
[<c01c43b8>] (hrtimer_active) from [<c01c50f4>] (hrtimer_try_to_cancel+0x24/0x140)
[<c01c50f4>] (hrtimer_try_to_cancel) from [<c01c5224>] (hrtimer_cancel+0x14/0x4c)
[<c01c5224>] (hrtimer_cancel) from [<bf1cae24>] (gpio_keys_attr_store_helper+0x1b8/0x1d8 [gpio_keys])
[<bf1cae24>] (gpio_keys_attr_store_helper [gpio_keys]) from [<bf1cae80>] (gpio_keys_store_disabled_keys+0x18/0x24 [gpio_keys])
[<bf1cae80>] (gpio_keys_store_disabled_keys [gpio_keys]) from [<c038ec7c>] (kernfs_fop_write_iter+0x10c/0x1cc)
[<c038ec7c>] (kernfs_fop_write_iter) from [<c02df858>] (vfs_write+0x2ac/0x404)
[<c02df858>] (vfs_write) from [<c02dfaf4>] (ksys_write+0x64/0xdc)
[<c02dfaf4>] (ksys_write) from [<c0100080>] (ret_fast_syscall+0x0/0x58)
Let's fix it up.
Fixes: c9efb0ba281e ("Input: gpio-keys - use hrtimer for software debounce, if possible")
Reported-by: Tony Lindgren <[email protected]>
Signed-off-by: Dmitry Torokhov <[email protected]>
---
Tony, could you please try this patch and see if it fixes the crash you
observed?
Thanks!
drivers/input/keyboard/gpio_keys.c | 30 +++++++++++++-----------------
1 file changed, 13 insertions(+), 17 deletions(-)
diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
index fe8fc76ee22e..8dbf1e69c90a 100644
--- a/drivers/input/keyboard/gpio_keys.c
+++ b/drivers/input/keyboard/gpio_keys.c
@@ -125,6 +125,18 @@ static const unsigned long *get_bm_events_by_type(struct input_dev *dev,
return (type == EV_KEY) ? dev->keybit : dev->swbit;
}
+static void gpio_keys_quiesce_key(void *data)
+{
+ struct gpio_button_data *bdata = data;
+
+ if (!bdata->gpiod)
+ hrtimer_cancel(&bdata->release_timer);
+ if (bdata->debounce_use_hrtimer)
+ hrtimer_cancel(&bdata->debounce_timer);
+ else
+ cancel_delayed_work_sync(&bdata->work);
+}
+
/**
* gpio_keys_disable_button() - disables given GPIO button
* @bdata: button data for button to be disabled
@@ -145,12 +157,7 @@ static void gpio_keys_disable_button(struct gpio_button_data *bdata)
* Disable IRQ and associated timer/work structure.
*/
disable_irq(bdata->irq);
-
- if (bdata->debounce_use_hrtimer)
- hrtimer_cancel(&bdata->release_timer);
- else
- cancel_delayed_work_sync(&bdata->work);
-
+ gpio_keys_quiesce_key(bdata);
bdata->disabled = true;
}
}
@@ -492,16 +499,6 @@ static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id)
return IRQ_HANDLED;
}
-static void gpio_keys_quiesce_key(void *data)
-{
- struct gpio_button_data *bdata = data;
-
- if (bdata->debounce_use_hrtimer)
- hrtimer_cancel(&bdata->debounce_timer);
- else
- cancel_delayed_work_sync(&bdata->work);
-}
-
static int gpio_keys_setup_key(struct platform_device *pdev,
struct input_dev *input,
struct gpio_keys_drvdata *ddata,
@@ -635,7 +632,6 @@ static int gpio_keys_setup_key(struct platform_device *pdev,
}
bdata->release_delay = button->debounce_interval;
- bdata->debounce_use_hrtimer = true;
hrtimer_init(&bdata->release_timer,
CLOCK_REALTIME, HRTIMER_MODE_REL_HARD);
bdata->release_timer.function = gpio_keys_irq_timer;
--
2.31.0.208.g409f899ff0-goog
--
Dmitry
* Dmitry Torokhov <[email protected]> [210407 05:30]:
> My brain-damaged adjustments to Paul's patch caused crashes in
> gpio_keys_disable_button() when driver is used in GPIO-less (i.e.
> purely interrupt-driven) setups, because I mixed together debounce and
> release timers when they are in fact separate:
>
> Unable to handle kernel NULL pointer dereference at virtual address 0000000c
> ...
> PC is at hrtimer_active+0xc/0x98
> LR is at hrtimer_try_to_cancel+0x24/0x140
> ...
> [<c01c43b8>] (hrtimer_active) from [<c01c50f4>] (hrtimer_try_to_cancel+0x24/0x140)
> [<c01c50f4>] (hrtimer_try_to_cancel) from [<c01c5224>] (hrtimer_cancel+0x14/0x4c)
> [<c01c5224>] (hrtimer_cancel) from [<bf1cae24>] (gpio_keys_attr_store_helper+0x1b8/0x1d8 [gpio_keys])
> [<bf1cae24>] (gpio_keys_attr_store_helper [gpio_keys]) from [<bf1cae80>] (gpio_keys_store_disabled_keys+0x18/0x24 [gpio_keys])
> [<bf1cae80>] (gpio_keys_store_disabled_keys [gpio_keys]) from [<c038ec7c>] (kernfs_fop_write_iter+0x10c/0x1cc)
> [<c038ec7c>] (kernfs_fop_write_iter) from [<c02df858>] (vfs_write+0x2ac/0x404)
> [<c02df858>] (vfs_write) from [<c02dfaf4>] (ksys_write+0x64/0xdc)
> [<c02dfaf4>] (ksys_write) from [<c0100080>] (ret_fast_syscall+0x0/0x58)
>
> Let's fix it up.
>
> Fixes: c9efb0ba281e ("Input: gpio-keys - use hrtimer for software debounce, if possible")
> Reported-by: Tony Lindgren <[email protected]>
> Signed-off-by: Dmitry Torokhov <[email protected]>
> ---
>
> Tony, could you please try this patch and see if it fixes the crash you
> observed?
Yes great, thanks this works for me:
Tested-by: Tony Lindgren <[email protected]>