[PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[Dmitry Torokhov]

From: Andrzej Pietrasiewicz <andrzej.p@collabora.com>

Use the new helper. Inspecting input device's 'users' member needs to be
done under device's mutex, so add appropriate invocations.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Link: https://lore.kernel.org/r/20200608112211.12125-7-andrzej.p@collabora.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---

Not sure how this got stuck in my patch queue but it is still valid...

 drivers/platform/x86/lenovo/thinkpad_acpi.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c b/drivers/platform/x86/lenovo/thinkpad_acpi.c
index 445e1403308e..f8e116e8a65d 100644
--- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
+++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
@@ -2547,9 +2547,10 @@ static void hotkey_poll_setup(const bool may_warn)
 
 	lockdep_assert_held(&hotkey_mutex);
 
+	mutex_lock(&tpacpi_inputdev->mutex);
 	if (hotkey_poll_freq > 0 &&
 	    (poll_driver_mask ||
-	     (poll_user_mask && tpacpi_inputdev->users > 0))) {
+	     (poll_user_mask && input_device_enabled(tpacpi_inputdev)))) {
 		if (!tpacpi_hotkey_task) {
 			tpacpi_hotkey_task = kthread_run(hotkey_kthread,
 					NULL, TPACPI_NVRAM_KTHREAD_NAME);
@@ -2566,6 +2567,7 @@ static void hotkey_poll_setup(const bool may_warn)
 				  poll_user_mask, poll_driver_mask);
 		}
 	}
+	mutex_unlock(&tpacpi_inputdev->mutex);
 }
 
 static void hotkey_poll_setup_safe(const bool may_warn)
-- 
2.55.0.571.g244d577d93-goog


-- 
Dmitry

Re: [PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[Mark Pearson]

On Wed, Aug 5, 2026, at 12:03 AM, Dmitry Torokhov wrote:
> From: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
>
> Use the new helper. Inspecting input device's 'users' member needs to be
> done under device's mutex, so add appropriate invocations.
>
> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
> Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
> Link: https://lore.kernel.org/r/20200608112211.12125-7-andrzej.p@collabora.com
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---
>
> Not sure how this got stuck in my patch queue but it is still valid...
>
>  drivers/platform/x86/lenovo/thinkpad_acpi.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c 
> b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> index 445e1403308e..f8e116e8a65d 100644
> --- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
> +++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> @@ -2547,9 +2547,10 @@ static void hotkey_poll_setup(const bool 
> may_warn)
> 
>  	lockdep_assert_held(&hotkey_mutex);
> 
> +	mutex_lock(&tpacpi_inputdev->mutex);
>  	if (hotkey_poll_freq > 0 &&
>  	    (poll_driver_mask ||
> -	     (poll_user_mask && tpacpi_inputdev->users > 0))) {
> +	     (poll_user_mask && input_device_enabled(tpacpi_inputdev)))) {
>  		if (!tpacpi_hotkey_task) {
>  			tpacpi_hotkey_task = kthread_run(hotkey_kthread,
>  					NULL, TPACPI_NVRAM_KTHREAD_NAME);
> @@ -2566,6 +2567,7 @@ static void hotkey_poll_setup(const bool may_warn)
>  				  poll_user_mask, poll_driver_mask);
>  		}
>  	}
> +	mutex_unlock(&tpacpi_inputdev->mutex);
>  }
> 
>  static void hotkey_poll_setup_safe(const bool may_warn)
> -- 

Looks good to me.

Only note is that can you use guard(mutex)(&tpacpi_inputdev->mutex) instead of the lock/unlock? I think that's preferred these days.

Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>

Re: [PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[Dmitry Torokhov]

Hi Mark,

On Wed, Aug 05, 2026 at 10:51:53AM -0400, Mark Pearson wrote:
> 
> 
> On Wed, Aug 5, 2026, at 12:03 AM, Dmitry Torokhov wrote:
> > From: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
> >
> > Use the new helper. Inspecting input device's 'users' member needs to be
> > done under device's mutex, so add appropriate invocations.
> >
> > Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
> > Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
> > Link: https://lore.kernel.org/r/20200608112211.12125-7-andrzej.p@collabora.com
> > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> > ---
> >
> > Not sure how this got stuck in my patch queue but it is still valid...
> >
> >  drivers/platform/x86/lenovo/thinkpad_acpi.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c 
> > b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> > index 445e1403308e..f8e116e8a65d 100644
> > --- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
> > +++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> > @@ -2547,9 +2547,10 @@ static void hotkey_poll_setup(const bool 
> > may_warn)
> > 
> >  	lockdep_assert_held(&hotkey_mutex);
> > 
> > +	mutex_lock(&tpacpi_inputdev->mutex);
> >  	if (hotkey_poll_freq > 0 &&
> >  	    (poll_driver_mask ||
> > -	     (poll_user_mask && tpacpi_inputdev->users > 0))) {
> > +	     (poll_user_mask && input_device_enabled(tpacpi_inputdev)))) {
> >  		if (!tpacpi_hotkey_task) {
> >  			tpacpi_hotkey_task = kthread_run(hotkey_kthread,
> >  					NULL, TPACPI_NVRAM_KTHREAD_NAME);
> > @@ -2566,6 +2567,7 @@ static void hotkey_poll_setup(const bool may_warn)
> >  				  poll_user_mask, poll_driver_mask);
> >  		}
> >  	}
> > +	mutex_unlock(&tpacpi_inputdev->mutex);
> >  }
> > 
> >  static void hotkey_poll_setup_safe(const bool may_warn)
> > -- 
> 
> Looks good to me.
> 
> Only note is that can you use guard(mutex)(&tpacpi_inputdev->mutex) instead of the lock/unlock? I think that's preferred these days.

If that is desired the whole driver needs converting. I can do it in a
separate patch(es) if you want.

> 
> Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>

Thanks.

-- 
Dmitry

Re: [PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[Mark Pearson]

On Wed, Aug 5, 2026, at 11:52 AM, Dmitry Torokhov wrote:
> Hi Mark,
>
> On Wed, Aug 05, 2026 at 10:51:53AM -0400, Mark Pearson wrote:
>> 
>> 
>> On Wed, Aug 5, 2026, at 12:03 AM, Dmitry Torokhov wrote:
>> > From: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
>> >
>> > Use the new helper. Inspecting input device's 'users' member needs to be
>> > done under device's mutex, so add appropriate invocations.
>> >
>> > Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
>> > Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
>> > Link: https://lore.kernel.org/r/20200608112211.12125-7-andrzej.p@collabora.com
>> > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
>> > ---
>> >
>> > Not sure how this got stuck in my patch queue but it is still valid...
>> >
>> >  drivers/platform/x86/lenovo/thinkpad_acpi.c | 4 +++-
>> >  1 file changed, 3 insertions(+), 1 deletion(-)
>> >
>> > diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c 
>> > b/drivers/platform/x86/lenovo/thinkpad_acpi.c
>> > index 445e1403308e..f8e116e8a65d 100644
>> > --- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
>> > +++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
>> > @@ -2547,9 +2547,10 @@ static void hotkey_poll_setup(const bool 
>> > may_warn)
>> > 
>> >  	lockdep_assert_held(&hotkey_mutex);
>> > 
>> > +	mutex_lock(&tpacpi_inputdev->mutex);
>> >  	if (hotkey_poll_freq > 0 &&
>> >  	    (poll_driver_mask ||
>> > -	     (poll_user_mask && tpacpi_inputdev->users > 0))) {
>> > +	     (poll_user_mask && input_device_enabled(tpacpi_inputdev)))) {
>> >  		if (!tpacpi_hotkey_task) {
>> >  			tpacpi_hotkey_task = kthread_run(hotkey_kthread,
>> >  					NULL, TPACPI_NVRAM_KTHREAD_NAME);
>> > @@ -2566,6 +2567,7 @@ static void hotkey_poll_setup(const bool may_warn)
>> >  				  poll_user_mask, poll_driver_mask);
>> >  		}
>> >  	}
>> > +	mutex_unlock(&tpacpi_inputdev->mutex);
>> >  }
>> > 
>> >  static void hotkey_poll_setup_safe(const bool may_warn)
>> > -- 
>> 
>> Looks good to me.
>> 
>> Only note is that can you use guard(mutex)(&tpacpi_inputdev->mutex) instead of the lock/unlock? I think that's preferred these days.
>
> If that is desired the whole driver needs converting. I can do it in a
> separate patch(es) if you want.
>
Ah - good point. Not worth it for this IMO, unless the more experienced maintainers have a strong opinion :)

Mark

Re: [PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[Dmitry Torokhov]

On Wed, Aug 05, 2026 at 12:15:27PM -0400, Mark Pearson wrote:
> 
> 
> On Wed, Aug 5, 2026, at 11:52 AM, Dmitry Torokhov wrote:
> > Hi Mark,
> >
> > On Wed, Aug 05, 2026 at 10:51:53AM -0400, Mark Pearson wrote:
> >> 
> >> 
> >> On Wed, Aug 5, 2026, at 12:03 AM, Dmitry Torokhov wrote:
> >> > From: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
> >> >
> >> > Use the new helper. Inspecting input device's 'users' member needs to be
> >> > done under device's mutex, so add appropriate invocations.
> >> >
> >> > Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
> >> > Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
> >> > Link: https://lore.kernel.org/r/20200608112211.12125-7-andrzej.p@collabora.com
> >> > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> >> > ---
> >> >
> >> > Not sure how this got stuck in my patch queue but it is still valid...
> >> >
> >> >  drivers/platform/x86/lenovo/thinkpad_acpi.c | 4 +++-
> >> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >> >
> >> > diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c 
> >> > b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> >> > index 445e1403308e..f8e116e8a65d 100644
> >> > --- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
> >> > +++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> >> > @@ -2547,9 +2547,10 @@ static void hotkey_poll_setup(const bool 
> >> > may_warn)
> >> > 
> >> >  	lockdep_assert_held(&hotkey_mutex);
> >> > 
> >> > +	mutex_lock(&tpacpi_inputdev->mutex);
> >> >  	if (hotkey_poll_freq > 0 &&
> >> >  	    (poll_driver_mask ||
> >> > -	     (poll_user_mask && tpacpi_inputdev->users > 0))) {
> >> > +	     (poll_user_mask && input_device_enabled(tpacpi_inputdev)))) {
> >> >  		if (!tpacpi_hotkey_task) {
> >> >  			tpacpi_hotkey_task = kthread_run(hotkey_kthread,
> >> >  					NULL, TPACPI_NVRAM_KTHREAD_NAME);
> >> > @@ -2566,6 +2567,7 @@ static void hotkey_poll_setup(const bool may_warn)
> >> >  				  poll_user_mask, poll_driver_mask);
> >> >  		}
> >> >  	}
> >> > +	mutex_unlock(&tpacpi_inputdev->mutex);
> >> >  }
> >> > 
> >> >  static void hotkey_poll_setup_safe(const bool may_warn)
> >> > -- 
> >> 
> >> Looks good to me.
> >> 
> >> Only note is that can you use guard(mutex)(&tpacpi_inputdev->mutex) instead of the lock/unlock? I think that's preferred these days.
> >
> > If that is desired the whole driver needs converting. I can do it in a
> > separate patch(es) if you want.
> >
> Ah - good point. Not worth it for this IMO, unless the more experienced maintainers have a strong opinion :)

Well, I went and did it anyways in case you want to apply it.

Thanks.

-- 
Dmitry

Re: [PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[Ilpo Järvinen]

On Tue, 04 Aug 2026 21:03:36 -0700, Dmitry Torokhov wrote:

> Use the new helper. Inspecting input device's 'users' member needs to be
> done under device's mutex, so add appropriate invocations.

Thank you for your contribution, it has been applied to my local
review-ilpo-next branch. Note it will show up in the public
platform-drivers-x86/review-ilpo-next branch only once I've pushed my
local branch there, which might take a while.

FYI [if applicable to your patch], as per Linus' policy change, also
fixes are mostly routed through for-next unless the fix is for a
commit introduced in the most recent cycle or is clearly a regression
fix.

The list of commits applied:
[1/1] platform/x86: thinkpad_acpi: Use input_device_enabled()
      commit: be0048786d53375fa4eace15cfdf65593956a1a2

--
 i.

Re: [PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[Ali Ahmet Memiş]

On Tue, Sep 15, 2026 at 02:32:34PM +0300, Ilpo Järvinen wrote:
> [1/1] platform/x86: thinkpad_acpi: Use input_device_enabled()
>       commit: be0048786d53375fa4eace15cfdf65593956a1a2

This hangs on module load for me. hotkey_inputdev_open() gets
called from input_open_device() with dev->mutex already held, so the
new lock in hotkey_poll_setup() deadlocks:

  INFO: task insmod:28182 is blocked on a mutex likely owned by task insmod:28182.
   hotkey_poll_setup+0x50/0x140 [thinkpad_acpi]
   hotkey_inputdev_open+0x36/0x50 [thinkpad_acpi]
   input_open_device+0x9d/0x130
   kbd_connect+0x8f/0xb0

I guess hotkey_inputdev_close() has the same issue. This was
next-20260929's thinkpad_acpi.c built against 7.1.11.

Re: [PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[Dmitry Torokhov]

On Wed, Sep 30, 2026 at 10:58:29AM +0300, Ali Ahmet Memiş wrote:
> On Tue, Sep 15, 2026 at 02:32:34PM +0300, Ilpo Järvinen wrote:
> > [1/1] platform/x86: thinkpad_acpi: Use input_device_enabled()
> >       commit: be0048786d53375fa4eace15cfdf65593956a1a2
> 
> This hangs on module load for me. hotkey_inputdev_open() gets
> called from input_open_device() with dev->mutex already held, so the
> new lock in hotkey_poll_setup() deadlocks:
> 
>   INFO: task insmod:28182 is blocked on a mutex likely owned by task insmod:28182.
>    hotkey_poll_setup+0x50/0x140 [thinkpad_acpi]
>    hotkey_inputdev_open+0x36/0x50 [thinkpad_acpi]
>    input_open_device+0x9d/0x130
>    kbd_connect+0x8f/0xb0
> 
> I guess hotkey_inputdev_close() has the same issue. This was
> next-20260929's thinkpad_acpi.c built against 7.1.11.

Hmm, indeed. I wonder if below will fox this for you.

-- 
Dmitry

platform/x86: thinkpad_acpi: fix deadlock in hotkey input open/close

Commit d6479c25ecef ("platform/x86: thinkpad_acpi: Use
input_device_enabled()") changed hotkey_poll_setup() to acquire
tpacpi_inputdev->mutex and call input_device_enabled(tpacpi_inputdev).

However, the input core already holds dev->mutex when invoking a
device's open() and close() callbacks. Because hotkey_inputdev_open()
and hotkey_inputdev_close() call into hotkey_poll_setup(), attempting to
acquire tpacpi_inputdev->mutex again results in an immediate
self-deadlock.

Additionally, locking tpacpi_inputdev->mutex inside hotkey_poll_setup()
while holding hotkey_mutex introduces an ABBA lock ordering inversion
with hotkey_inputdev_open() and hotkey_inputdev_close(), which acquire
hotkey_mutex while holding tpacpi_inputdev->mutex. Finally,
input_inhibit_device() calls dev->close() before setting dev->inhibited,
so input_device_enabled() still returns true inside
hotkey_inputdev_close().

Track whether the input device is active in a driver-local boolean
protected by hotkey_mutex instead of locking tpacpi_inputdev->mutex and
querying input_device_enabled().

Fixes: d6479c25ecef ("platform/x86: thinkpad_acpi: Use input_device_enabled()")
Assisted-by: LLM
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/platform/x86/lenovo/thinkpad_acpi.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c b/drivers/platform/x86/lenovo/thinkpad_acpi.c
index 1225b01ed14d..40e9763a12f8 100644
--- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
+++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
@@ -1887,6 +1887,7 @@ static u32 hotkey_reserved_mask;	/* events better left disabled */
 static u32 hotkey_driver_mask;		/* events needed by the driver */
 static u32 hotkey_user_mask;		/* events visible to userspace */
 static u32 hotkey_acpi_mask;		/* events enabled in firmware */
+static bool hotkey_input_enabled;
 
 static bool tpacpi_driver_event(const unsigned int hkey_event);
 static void hotkey_poll_setup(const bool may_warn);
@@ -2544,10 +2545,8 @@ static void hotkey_poll_setup(const bool may_warn)
 
 	lockdep_assert_held(&hotkey_mutex);
 
-	guard(mutex)(&tpacpi_inputdev->mutex);
 	if (hotkey_poll_freq > 0 &&
-	    (poll_driver_mask ||
-	     (poll_user_mask && input_device_enabled(tpacpi_inputdev)))) {
+	    (poll_driver_mask || (poll_user_mask && hotkey_input_enabled))) {
 		if (!tpacpi_hotkey_task) {
 			tpacpi_hotkey_task = kthread_run(hotkey_kthread,
 					NULL, TPACPI_NVRAM_KTHREAD_NAME);
@@ -2602,7 +2601,10 @@ static int hotkey_inputdev_open(struct input_dev *dev)
 	switch (tpacpi_lifecycle) {
 	case TPACPI_LIFE_INIT:
 	case TPACPI_LIFE_RUNNING:
-		hotkey_poll_setup_safe(false);
+		scoped_guard(mutex, &hotkey_mutex) {
+			hotkey_input_enabled = true;
+			hotkey_poll_setup(false);
+		}
 		return 0;
 	case TPACPI_LIFE_EXITING:
 		return -EBUSY;
@@ -2615,10 +2617,14 @@ static int hotkey_inputdev_open(struct input_dev *dev)
 
 static void hotkey_inputdev_close(struct input_dev *dev)
 {
+	guard(mutex)(&hotkey_mutex);
+
+	hotkey_input_enabled = false;
+
 	/* disable hotkey polling when possible */
 	if (tpacpi_lifecycle != TPACPI_LIFE_EXITING &&
 	    !(hotkey_source_mask & hotkey_driver_mask))
-		hotkey_poll_setup_safe(false);
+		hotkey_poll_setup(false);
 }
 
 /* sysfs hotkey enable ------------------------------------------------- */
-- 
2.56.0.rc1.315.gc6ed9934b7-goog

Re: [PATCH] platform/x86: thinkpad_acpi: Use input_device_enabled()

[Ali Ahmet Memiş]

On Wed, Sep 30, 2026 at 12:37:54PM -0700, Dmitry Torokhov wrote:
> Hmm, indeed. I wonder if below will fox this for you.

Yes, it loads fine now. I also toggled inhibited on the input device
with polling enabled, and the nvram thread stops and starts again as
expected.

Tested-by: Ali Ahmet Memiş <aliamemis@disroot.org>