Re: [Patch v2] media: s5p-mfc: Corrected NV12M/NV21M plane-sizes
From: Nicolas Dufresne <hidden>
Date: 2025-02-28 02:26:11
Also in:
linux-media, linux-samsung-soc, lkml
Hi, Le mercredi 26 février 2025 à 15:52 +0530, Aakarsh Jain a écrit :
quoted hunk ↗ jump to hunk
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 <redacted> Signed-off-by: Aakarsh Jain <redacted> --- 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);
An eventual port to v4l2-common helpers instead of open coding this would be nice, though I see nothing wrong to report with this code, so: Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com> regards, Nicolas
break; case V4L2_PIX_FMT_YUV420M: case V4L2_PIX_FMT_YVU420M: