Hi, On 07/03/23 18:50, Javier Martinez Canillas wrote: > There are DRM fourcc formats that have pixels smaller than a byte, but the > conversion_buf_size() function assumes that pixels are a multiple of bytes > and use the struct drm_format_info .cpp field to calculate the dst_pitch. > > Instead, calculate it by using the bits per pixel (bpp) and divide it by 8 > to account for formats that have sub-byte pixels. > > Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx> > --- > Tested by making sure that the following command still succeeds: > > ./tools/testing/kunit/kunit.py run \ > --kunitconfig=drivers/gpu/drm/tests/.kunitconfig > > Changes in v2: > - Drop an unused variable, that was pointed out by the kernel robot. > > drivers/gpu/drm/tests/drm_format_helper_test.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/tests/drm_format_helper_test.c b/drivers/gpu/drm/tests/drm_format_helper_test.c > index 9536829c6e3a..84b5cc29c8fc 100644 > --- a/drivers/gpu/drm/tests/drm_format_helper_test.c > +++ b/drivers/gpu/drm/tests/drm_format_helper_test.c > @@ -409,12 +409,15 @@ static size_t conversion_buf_size(u32 dst_format, unsigned int dst_pitch, > const struct drm_rect *clip) > { > const struct drm_format_info *dst_fi = drm_format_info(dst_format); > + unsigned int bpp; > > if (!dst_fi) > return -EINVAL; > > - if (!dst_pitch) > - dst_pitch = drm_rect_width(clip) * dst_fi->cpp[0]; > + if (!dst_pitch) { > + bpp = drm_format_info_bpp(dst_fi, 0); > + dst_pitch = DIV_ROUND_UP(drm_rect_width(clip) * bpp, 8); > + } > > return dst_pitch * drm_rect_height(clip); > } Ran it on UML, arm and powerpc with my patch above it, All looks good :). Reviewed-by: Arthur Grillo <arthurgrillo@xxxxxxxxxx> Thanks, Grillo