On Fri, Sep 2, 2022 at 9:42 AM Li Zhong <floridsleeves@xxxxxxxxx> wrote:
>
> Check return status of acpi_get_parent() to confirm whether it fails.
>
> Signed-off-by: Li Zhong <floridsleeves@xxxxxxxxx>
> ---
> drivers/acpi/acpi_video.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
> index 5cbe2196176d..5fca9a39b1a4 100644
> --- a/drivers/acpi/acpi_video.c
> +++ b/drivers/acpi/acpi_video.c
> @@ -1,4 +1,4 @@
> -// SPDX-License-Identifier: GPL-2.0-or-later
> + // SPDX-License-Identifier: GPL-2.0-or-later
This change surely is not intended?
> /*
> * video.c - ACPI Video Driver
> *
> @@ -1753,6 +1753,7 @@ static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
> int result;
> static int count;
> char *name;
> + acpi_status status;
>
> result = acpi_video_init_brightness(device);
> if (result)
> @@ -1766,8 +1767,9 @@ static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
> return;
> count++;
>
> - acpi_get_parent(device->dev->handle, &acpi_parent);
> -
> + status = acpi_get_parent(device->dev->handle, &acpi_parent);
> + if (ACPI_FAILURE(status))
> + return;
But device->dev->handle is known to be valid, so the only case in
which acpi_get_parent() above can fail is when the given namespace
object has no parent, in which case acpi_parent will be NULL, so that
should be caught my the check below, shouldn't it?
> pdev = acpi_get_pci_dev(acpi_parent);
> if (pdev) {
> parent = &pdev->dev;
> --
