2022-03-17 09:33:29

by Geert Uytterhoeven

Subject: [PATCH v2 5/5] drm/repaper: Reduce temporary buffer size in repaper_fb_dirty()

As the temporary buffer is no longer used to store 8-bit grayscale data,
its size can be reduced to the size needed to store the monochrome
bitmap data.

Fixes: 24c6bedefbe71de9 ("drm/repaper: Use format helper for xrgb8888 to monochrome conversion")
Signed-off-by: Geert Uytterhoeven <[email protected]>
Reviewed-by: Javier Martinez Canillas <[email protected]>
---
v2:
- Add Reviewed-by.

Untested due to lack of hardware.

I replaced kmalloc_array() by kmalloc() to match size calculations in
other locations in this driver. There is no point in handling a
possible multiplication overflow only here.
---
drivers/gpu/drm/tiny/repaper.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tiny/repaper.c b/drivers/gpu/drm/tiny/repaper.c
index a096fb8b83e99dc8..7738b87f370ad147 100644
--- a/drivers/gpu/drm/tiny/repaper.c
+++ b/drivers/gpu/drm/tiny/repaper.c
@@ -530,7 +530,7 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb)
DRM_DEBUG("Flushing [FB:%d] st=%ums\n", fb->base.id,
epd->factored_stage_time);

- buf = kmalloc_array(fb->width, fb->height, GFP_KERNEL);
+ buf = kmalloc(fb->width * fb->height / 8, GFP_KERNEL);
if (!buf) {
ret = -ENOMEM;
goto out_exit;
--
2.25.1

2023-07-29 20:40:39

by Javier Martinez Canillas

Subject: Re: [PATCH v2 5/5] drm/repaper: Reduce temporary buffer size in repaper_fb_dirty()

Geert Uytterhoeven <[email protected]> writes:

> As the temporary buffer is no longer used to store 8-bit grayscale data,
> its size can be reduced to the size needed to store the monochrome
> bitmap data.
>
> Fixes: 24c6bedefbe71de9 ("drm/repaper: Use format helper for xrgb8888 to monochrome conversion")
> Signed-off-by: Geert Uytterhoeven <[email protected]>
> Reviewed-by: Javier Martinez Canillas <[email protected]>
> ---

Pushed to drm-misc (drm-misc-next). Thanks!

--
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat