2022-04-13 08:39:51

by Xiaomeng Tong

Subject: [PATCH v3] drm/gma500: fix a potential repeat execution in psb_driver_load

Instead of exiting the loop as expected when an entry is found, the
list_for_each_entry() continues until the traversal is complete. To
avoid potential executing 'ret = gma_backlight_init(dev);' repeatly,
goto outside the loop when found entry by replacing switch/case with
if statement.

Signed-off-by: Xiaomeng Tong <[email protected]>
---
changes since v2:
- replace switch with if statement (Patrik Jakobsson)

changes since v1:
- goto outside the loop (Xiaomeng Tong)

v2: https://lore.kernel.org/dri-devel/[email protected]/
v1: https://lore.kernel.org/lkml/[email protected]/
---
drivers/gpu/drm/gma500/psb_drv.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/gma500/psb_drv.c b/drivers/gpu/drm/gma500/psb_drv.c
index 2aff54d505e2..85211ec16e52 100644
--- a/drivers/gpu/drm/gma500/psb_drv.c
+++ b/drivers/gpu/drm/gma500/psb_drv.c
@@ -396,9 +396,8 @@ static int psb_driver_load(struct drm_device *dev, unsigned long flags)
drm_for_each_connector_iter(connector, &conn_iter) {
gma_encoder = gma_attached_encoder(connector);

- switch (gma_encoder->type) {
- case INTEL_OUTPUT_LVDS:
- case INTEL_OUTPUT_MIPI:
+ if (gma_encoder->type == INTEL_OUTPUT_LVDS ||
+ gma_encoder->type == INTEL_OUTPUT_MIPI) {
ret = gma_backlight_init(dev);
break;
}
--
2.17.1

2022-04-20 12:16:04

by Patrik Jakobsson

Subject: Re: [PATCH v3] drm/gma500: fix a potential repeat execution in psb_driver_load

On Wed, Apr 13, 2022 at 7:11 AM Xiaomeng Tong <[email protected]> wrote:
>
> Instead of exiting the loop as expected when an entry is found, the
> list_for_each_entry() continues until the traversal is complete. To
> avoid potential executing 'ret = gma_backlight_init(dev);' repeatly,
> goto outside the loop when found entry by replacing switch/case with
> if statement.
>
> Signed-off-by: Xiaomeng Tong <[email protected]>

Thanks for the patch. I've applied it to drm-misc-next.

I fixed up an indentation issue on the second line.

Cheers
Patrik

> ---
> changes since v2:
> - replace switch with if statement (Patrik Jakobsson)
>
> changes since v1:
> - goto outside the loop (Xiaomeng Tong)
>
> v2: https://lore.kernel.org/dri-devel/[email protected]/
> v1: https://lore.kernel.org/lkml/[email protected]/
> ---
> drivers/gpu/drm/gma500/psb_drv.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/gma500/psb_drv.c b/drivers/gpu/drm/gma500/psb_drv.c
> index 2aff54d505e2..85211ec16e52 100644
> --- a/drivers/gpu/drm/gma500/psb_drv.c
> +++ b/drivers/gpu/drm/gma500/psb_drv.c
> @@ -396,9 +396,8 @@ static int psb_driver_load(struct drm_device *dev, unsigned long flags)
> drm_for_each_connector_iter(connector, &conn_iter) {
> gma_encoder = gma_attached_encoder(connector);
>
> - switch (gma_encoder->type) {
> - case INTEL_OUTPUT_LVDS:
> - case INTEL_OUTPUT_MIPI:
> + if (gma_encoder->type == INTEL_OUTPUT_LVDS ||
> + gma_encoder->type == INTEL_OUTPUT_MIPI) {
> ret = gma_backlight_init(dev);
> break;
> }
> --
> 2.17.1
>