On 10/21/25 7:57 AM, Thomas Zimmermann wrote:
Am 21.10.25 um 08:51 schrieb Thomas Zimmermann:
Hi
Am 20.10.25 um 13:57 schrieb Mehdi Ben Hadj Khelifa:
Use drm_format_info_min_pitch() to calculate the framebuffer line pitch
instead of directly multiplying width and height. This aligns with DRM
helpers for determining per-line byte size and avoids manual assumptions
about bytes per pixel.
Suggested-by: Thomas Zimmermann <[email protected]>
Signed-off-by: Mehdi Ben Hadj Khelifa <[email protected]>
---
drivers/gpu/drm/tiny/repaper.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/tiny/repaper.c b/drivers/gpu/drm/tiny/
repaper.c
index 4824f863fdba..aeff49bc6ba7 100644
--- a/drivers/gpu/drm/tiny/repaper.c
+++ b/drivers/gpu/drm/tiny/repaper.c
@@ -517,6 +517,8 @@ static int repaper_fb_dirty(struct
drm_framebuffer *fb, const struct iosys_map *
unsigned int dst_pitch = 0;
struct iosys_map dst;
struct drm_rect clip;
+ const struct drm_format_info *info = fb->format;
This is the wrong format. You're allocating the output buffer here,
but you're using the input format. IIUC the output format is
DRM_FORMAT_R1. The input is _XRGB8888.
Best regards
Thomas
+ size_t pitch;
int idx, ret = 0;
u8 *buf = NULL;
@@ -534,7 +536,9 @@ static int repaper_fb_dirty(struct
drm_framebuffer *fb, const struct iosys_map *
DRM_DEBUG("Flushing [FB:%d] st=%ums\n", fb->base.id,
epd->factored_stage_time);
- buf = kmalloc(fb->width * fb->height / 8, GFP_KERNEL);
+ pitch = drm_format_info_min_pitch(info, 0, fb->width);
+
+ buf = kmalloc_array(fb->height, pitch, GFP_KERNEL);
And TBH I'm not sure if we should really convert this call. It's not an
array in the sense of that API.
Good candidates look like 'kmalloc(count * sizeof(<some type or
variable>))'
I will leave kmalloc in v3. Do you want me to send deep testing
information on this patch?
BR,
Mehdi>>> if (!buf) {
ret = -ENOMEM;
goto out_exit;
