[Patch v2] media: s5p-mfc: Corrected NV12M/NV21M plane-sizes

[Marek Szyprowski]

On 26.02.2025 11:22, Aakarsh Jain wrote:
> There is a possibility of getting page fault if the overall
> buffer size is not aligned to 256bytes. Since MFC does read
> operation only and it won't corrupt the data values even if
> it reads the extra bytes.
> Corrected luma and chroma plane sizes for V4L2_PIX_FMT_NV12M
> and V4L2_PIX_FMT_NV21M pixel format.
>
> Suggested-by: Hans Verkuil <hverkuil-cisco at xs4all.nl>
> Signed-off-by: Aakarsh Jain <aakarsh.jain at samsung.com>
Acked-by: Marek Szyprowski <m.szyprowski at samsung.com>
> ---
> changelog:
> v1->v2
> Patch link: https://patchwork.kernel.org/project/linux-media/patch/20240806115714.29828-1-aakarsh.jain@samsung.com/
> Removed duplicate code and aligned luma and chroma size
> to multiple of 256bytes as suggested by Hans.
>   drivers/media/platform/samsung/s5p-mfc/s5p_mfc_opr_v6.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/platform/samsung/s5p-mfc/s5p_mfc_opr_v6.c b/drivers/media/platform/samsung/s5p-mfc/s5p_mfc_opr_v6.c
> index 73f7af674c01..0c636090d723 100644
> --- a/drivers/media/platform/samsung/s5p-mfc/s5p_mfc_opr_v6.c
> +++ b/drivers/media/platform/samsung/s5p-mfc/s5p_mfc_opr_v6.c
> @@ -549,8 +549,9 @@ static void s5p_mfc_enc_calc_src_size_v6(struct s5p_mfc_ctx *ctx)
>   		case V4L2_PIX_FMT_NV21M:
>   			ctx->stride[0] = ALIGN(ctx->img_width, S5P_FIMV_NV12M_HALIGN_V6);
>   			ctx->stride[1] = ALIGN(ctx->img_width, S5P_FIMV_NV12M_HALIGN_V6);
> -			ctx->luma_size = ctx->stride[0] * ALIGN(ctx->img_height, 16);
> -			ctx->chroma_size =  ctx->stride[0] * ALIGN(ctx->img_height / 2, 16);
> +			ctx->luma_size = ALIGN(ctx->stride[0] * ALIGN(ctx->img_height, 16), 256);
> +			ctx->chroma_size = ALIGN(ctx->stride[0] * ALIGN(ctx->img_height / 2, 16),
> +					256);
>   			break;
>   		case V4L2_PIX_FMT_YUV420M:
>   		case V4L2_PIX_FMT_YVU420M:

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland