Message ID | 20200608112211.12125-5-andrzej.p@collabora.com (mailing list archive) |
---|---|
State | Not Applicable |
Headers | show |
Series | [v4,1/7] Input: add input_device_enabled() | expand |
On Mon, Jun 08, 2020 at 01:22:08PM +0200, Andrzej Pietrasiewicz wrote: > A new helper is available, so use it. > > Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com> > --- > drivers/acpi/button.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c > index ff7ab291f678..4deb2b48d03c 100644 > --- a/drivers/acpi/button.c > +++ b/drivers/acpi/button.c > @@ -411,7 +411,7 @@ static void acpi_button_notify(struct acpi_device *device, u32 event) > input = button->input; > if (button->type == ACPI_BUTTON_TYPE_LID) { > mutex_lock(&button->input->mutex); > - users = button->input->users; > + users = input_device_enabled(button->input); > mutex_unlock(&button->input->mutex); > if (users) This chunk (pre-patch) is really wrong. 'users' value is obsolete and can not be trusted the moment we unlocked the mutex. "if" needs to be inside critical section. > acpi_lid_update_state(device, true); > @@ -460,7 +460,7 @@ static int acpi_button_resume(struct device *dev) > > button->suspended = false; > mutex_lock(&input->mutex); > - if (button->type == ACPI_BUTTON_TYPE_LID && input->users) { > + if (button->type == ACPI_BUTTON_TYPE_LID && input_device_enabled(input)) { > button->last_state = !!acpi_lid_evaluate_state(device); > button->last_time = ktime_get(); > acpi_lid_initialize_state(device); > -- > 2.17.1 > Thanks.
On Wed, Jun 24, 2020 at 10:24:46PM -0700, Dmitry Torokhov wrote: > On Mon, Jun 08, 2020 at 01:22:08PM +0200, Andrzej Pietrasiewicz wrote: > > A new helper is available, so use it. > > > > Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com> > > --- > > drivers/acpi/button.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c > > index ff7ab291f678..4deb2b48d03c 100644 > > --- a/drivers/acpi/button.c > > +++ b/drivers/acpi/button.c > > @@ -411,7 +411,7 @@ static void acpi_button_notify(struct acpi_device *device, u32 event) > > input = button->input; > > if (button->type == ACPI_BUTTON_TYPE_LID) { > > mutex_lock(&button->input->mutex); > > - users = button->input->users; > > + users = input_device_enabled(button->input); > > mutex_unlock(&button->input->mutex); > > if (users) > > This chunk (pre-patch) is really wrong. 'users' value is obsolete and > can not be trusted the moment we unlocked the mutex. "if" needs to be > inside critical section. So looking at this patch and the previous one again, I believe this driver is wrong to key the behavior off input->users and we should not apply either of the patches. I'll post another patch fixing this. Thanks.
diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c index ff7ab291f678..4deb2b48d03c 100644 --- a/drivers/acpi/button.c +++ b/drivers/acpi/button.c @@ -411,7 +411,7 @@ static void acpi_button_notify(struct acpi_device *device, u32 event) input = button->input; if (button->type == ACPI_BUTTON_TYPE_LID) { mutex_lock(&button->input->mutex); - users = button->input->users; + users = input_device_enabled(button->input); mutex_unlock(&button->input->mutex); if (users) acpi_lid_update_state(device, true); @@ -460,7 +460,7 @@ static int acpi_button_resume(struct device *dev) button->suspended = false; mutex_lock(&input->mutex); - if (button->type == ACPI_BUTTON_TYPE_LID && input->users) { + if (button->type == ACPI_BUTTON_TYPE_LID && input_device_enabled(input)) { button->last_state = !!acpi_lid_evaluate_state(device); button->last_time = ktime_get(); acpi_lid_initialize_state(device);
A new helper is available, so use it. Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com> --- drivers/acpi/button.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)