From: "dmitry.torokhov@gmail.com" dmitry.torokhov@gmail.com
stable inclusion from linux-4.19.155 commit 02e92557b3075b9d0e02dc8551ea14ac5955b996
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commit 21988a8e51479ceffe7b0568b170effabb708dfe upstream.
The original intent of 84d3f6b76447 was to delay evaluating lid state until all drivers have been loaded, with input device being opened from userspace serving as a signal for this condition. Let's ensure that state updates happen even if userspace closed (or in the future inhibited) input device.
Note that if we go through suspend/resume cycle we assume the system has been fully initialized even if LID input device has not been opened yet.
This has a side-effect of fixing access to input->users outside of input->mutex protections by the way of eliminating said accesses and using driver private flag.
Fixes: 84d3f6b76447 ("ACPI / button: Delay acpi_lid_initialize_state() until first user space open") Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Reviewed-by: Hans de Goede hdegoede@redhat.com Cc: 4.15+ stable@vger.kernel.org # 4.15+ Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/acpi/button.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c index d5c19e25ddf5..f43f5adc21b6 100644 --- a/drivers/acpi/button.c +++ b/drivers/acpi/button.c @@ -149,6 +149,7 @@ struct acpi_button { int last_state; ktime_t last_time; bool suspended; + bool lid_state_initialized; };
static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier); @@ -404,6 +405,8 @@ static int acpi_lid_update_state(struct acpi_device *device,
static void acpi_lid_initialize_state(struct acpi_device *device) { + struct acpi_button *button = acpi_driver_data(device); + switch (lid_init_state) { case ACPI_BUTTON_LID_INIT_OPEN: (void)acpi_lid_notify_state(device, 1); @@ -415,13 +418,14 @@ static void acpi_lid_initialize_state(struct acpi_device *device) default: break; } + + button->lid_state_initialized = true; }
static void acpi_button_notify(struct acpi_device *device, u32 event) { struct acpi_button *button = acpi_driver_data(device); struct input_dev *input; - int users;
switch (event) { case ACPI_FIXED_HARDWARE_EVENT: @@ -430,10 +434,7 @@ static void acpi_button_notify(struct acpi_device *device, u32 event) case ACPI_BUTTON_NOTIFY_STATUS: input = button->input; if (button->type == ACPI_BUTTON_TYPE_LID) { - mutex_lock(&button->input->mutex); - users = button->input->users; - mutex_unlock(&button->input->mutex); - if (users) + if (button->lid_state_initialized) acpi_lid_update_state(device, true); } else { int keycode; @@ -478,7 +479,7 @@ static int acpi_button_resume(struct device *dev) struct acpi_button *button = acpi_driver_data(device);
button->suspended = false; - if (button->type == ACPI_BUTTON_TYPE_LID && button->input->users) { + if (button->type == ACPI_BUTTON_TYPE_LID) { button->last_state = !!acpi_lid_evaluate_state(device); button->last_time = ktime_get(); acpi_lid_initialize_state(device);