From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F166E2505A7; Wed, 5 Mar 2025 17:54:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741197280; cv=none; b=cBdPcPZslwQ1WdJJZYyKVZymQmA+B6uVQwnpnO91mby3SPvPLBwY1e7VQLIMrOyRFwBgcMgzl4UwT3eJnIo+erLgte/fsMLyymF3WFn/12zGFDUqWcRa+MsF0Q/dZBV2k5pAlcqfYYou+BK/CcArUkbAkfISeiLaBg/xrMFbwjI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741197280; c=relaxed/simple; bh=CiArs+uF6qFGVfHgMkP8VyXDf0sJzhv3X6Hr1EM99vg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Kwt/70FFxKBSXTksznxh5r+njig52fkKPYyqsOdZdOAZw6B6WVM7auhom1BwwfWZMdR3b24g+HpjiDoqGNZYmtR/+/ZuK3396LL01WUCWc5sJcZMjHTZIPWzOjoyqJ/mMdV6AdVWI1At9FQUNhdFTdJIzwCHcQhbst6IyB0f3Vk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=sV3ZF1cf; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="sV3ZF1cf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7BEB0C4CEE2; Wed, 5 Mar 2025 17:54:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741197279; bh=CiArs+uF6qFGVfHgMkP8VyXDf0sJzhv3X6Hr1EM99vg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sV3ZF1cf4zQKMyzFroLATJaD27buLmo1nRu4r7+oblwqEEOmpZyCG1y0lmt9Hoy1u 1VJ8O1TSMRKjVf6EuQq1pka4OIumLBVipg3tNGE+OYA0atp/CKTcrisl4ZAKGKuCs2 53+AbHhZ1dxLS9DH5r9FOHDdSCc5SkPCNxG+Wggw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Marijn Suijten , Abhinav Kumar , Konrad Dybcio , Dmitry Baryshkov , Sasha Levin Subject: [PATCH 6.1 069/176] drm/msm/dpu: Dont leak bits_per_component into random DSC_ENC fields Date: Wed, 5 Mar 2025 18:47:18 +0100 Message-ID: <20250305174508.227785303@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250305174505.437358097@linuxfoundation.org> References: <20250305174505.437358097@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marijn Suijten [ Upstream commit 144429831f447223253a0e4376489f84ff37d1a7 ] What used to be the input_10_bits boolean - feeding into the lowest bit of DSC_ENC - on MSM downstream turned into an accidental OR with the full bits_per_component number when it was ported to the upstream kernel. On typical bpc=8 setups we don't notice this because line_buf_depth is always an odd value (it contains bpc+1) and will also set the 4th bit after left-shifting by 3 (hence this |= bits_per_component is a no-op). Now that guards are being removed to allow more bits_per_component values besides 8 (possible since commit 49fd30a7153b ("drm/msm/dsi: use DRM DSC helpers for DSC setup")), a bpc of 10 will instead clash with the 5th bit which is convert_rgb. This is "fortunately" also always set to true by MSM's dsi_populate_dsc_params() already, but once a bpc of 12 starts being used it'll write into simple_422 which is normally false. To solve all these overlaps, simply replicate downstream code and only set this lowest bit if bits_per_component is equal to 10. It is unclear why DSC requires this only for bpc=10 but not bpc=12, and also notice that this lowest bit wasn't set previously despite having a panel and patch on the list using it without any mentioned issues. Fixes: c110cfd1753e ("drm/msm/disp/dpu1: Add support for DSC") Signed-off-by: Marijn Suijten Reviewed-by: Abhinav Kumar Reviewed-by: Konrad Dybcio Reviewed-by: Dmitry Baryshkov Patchwork: https://patchwork.freedesktop.org/patch/636311/ Link: https://lore.kernel.org/r/20250211-dsc-10-bit-v1-1-1c85a9430d9a@somainline.org Signed-off-by: Abhinav Kumar Signed-off-by: Sasha Levin --- drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c index c8f14555834a8..70a6dfe94faa5 100644 --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c @@ -46,6 +46,7 @@ static void dpu_hw_dsc_config(struct dpu_hw_dsc *hw_dsc, u32 slice_last_group_size; u32 det_thresh_flatness; bool is_cmd_mode = !(mode & DSC_MODE_VIDEO); + bool input_10_bits = dsc->bits_per_component == 10; DPU_REG_WRITE(c, DSC_COMMON_MODE, mode); @@ -62,7 +63,7 @@ static void dpu_hw_dsc_config(struct dpu_hw_dsc *hw_dsc, data |= (dsc->line_buf_depth << 3); data |= (dsc->simple_422 << 2); data |= (dsc->convert_rgb << 1); - data |= dsc->bits_per_component; + data |= input_10_bits; DPU_REG_WRITE(c, DSC_ENC, data); -- 2.39.5