From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 470A2C433EF for ; Mon, 27 Dec 2021 15:45:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235692AbhL0Ppv (ORCPT ); Mon, 27 Dec 2021 10:45:51 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:42980 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239229AbhL0PlZ (ORCPT ); Mon, 27 Dec 2021 10:41:25 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 7599FB81063; Mon, 27 Dec 2021 15:41:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCA4DC36AE7; Mon, 27 Dec 2021 15:41:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1640619682; bh=k9qRjT4PPLjvZidYW2Nk0Nwn+tBZVx/kfsgZzH8mgQk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RENgXMqzC6nn9at+f/LoAKtBvU6K8mX5CbV9DsEEw4qVTdRAnW1gb0EKCaydBqVaA vkWKzWl9+Kp183yskA/zRODySh/U/mHVLj5IAet+C2SZ2dRhCCToJnQZS6Fy57NlFm LUhlWNjsMPsh1uB929nH0OIJIw6BBRubXinflCFU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, AngeloGioacchino Del Regno , Chun-Kuang Hu , Sasha Levin Subject: [PATCH 5.15 015/128] drm/mediatek: hdmi: Perform NULL pointer check for mtk_hdmi_conf Date: Mon, 27 Dec 2021 16:29:50 +0100 Message-Id: <20211227151332.033041957@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211227151331.502501367@linuxfoundation.org> References: <20211227151331.502501367@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: AngeloGioacchino Del Regno [ Upstream commit 3b8e19a0aa3933a785be9f1541afd8d398c4ec69 ] In commit 41ca9caaae0b ("drm/mediatek: hdmi: Add check for CEA modes only") a check for CEA modes was added to function mtk_hdmi_bridge_mode_valid() in order to address possible issues on MT8167; moreover, with commit c91026a938c2 ("drm/mediatek: hdmi: Add optional limit on maximal HDMI mode clock") another similar check was introduced. Unfortunately though, at the time of writing, MT8173 does not provide any mtk_hdmi_conf structure and this is crashing the kernel with NULL pointer upon entering mtk_hdmi_bridge_mode_valid(), which happens as soon as a HDMI cable gets plugged in. To fix this regression, add a NULL pointer check for hdmi->conf in the said function, restoring HDMI functionality and avoiding NULL pointer kernel panics. Fixes: 41ca9caaae0b ("drm/mediatek: hdmi: Add check for CEA modes only") Fixes: c91026a938c2 ("drm/mediatek: hdmi: Add optional limit on maximal HDMI mode clock") Signed-off-by: AngeloGioacchino Del Regno Signed-off-by: Chun-Kuang Hu Signed-off-by: Sasha Levin --- drivers/gpu/drm/mediatek/mtk_hdmi.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c index 5838c44cbf6f0..3196189429bcf 100644 --- a/drivers/gpu/drm/mediatek/mtk_hdmi.c +++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c @@ -1224,12 +1224,14 @@ static int mtk_hdmi_bridge_mode_valid(struct drm_bridge *bridge, return MODE_BAD; } - if (hdmi->conf->cea_modes_only && !drm_match_cea_mode(mode)) - return MODE_BAD; + if (hdmi->conf) { + if (hdmi->conf->cea_modes_only && !drm_match_cea_mode(mode)) + return MODE_BAD; - if (hdmi->conf->max_mode_clock && - mode->clock > hdmi->conf->max_mode_clock) - return MODE_CLOCK_HIGH; + if (hdmi->conf->max_mode_clock && + mode->clock > hdmi->conf->max_mode_clock) + return MODE_CLOCK_HIGH; + } if (mode->clock < 27000) return MODE_CLOCK_LOW; -- 2.34.1